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llvm-project/clang/lib/Sema/SemaDecl.cpp

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//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements semantic analysis for declarations.
//
//===----------------------------------------------------------------------===//
#include "clang/Sema/SemaInternal.h"
#include "TypeLocBuilder.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTLambda.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/CommentDiagnostic.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/EvaluatedExprVisitor.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/StmtCXX.h"
#include "clang/Basic/Builtins.h"
#include "clang/Basic/PartialDiagnostic.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Lex/HeaderSearch.h" // TODO: Sema shouldn't depend on Lex
#include "clang/Lex/Lexer.h" // TODO: Extract static functions to fix layering.
#include "clang/Lex/ModuleLoader.h" // TODO: Sema shouldn't depend on Lex
#include "clang/Lex/Preprocessor.h" // Included for isCodeCompletionEnabled()
#include "clang/Sema/CXXFieldCollector.h"
#include "clang/Sema/DeclSpec.h"
#include "clang/Sema/DelayedDiagnostic.h"
#include "clang/Sema/Initialization.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/ParsedTemplate.h"
#include "clang/Sema/Scope.h"
#include "clang/Sema/ScopeInfo.h"
#include "clang/Sema/Template.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Triple.h"
#include <algorithm>
#include <cstring>
#include <functional>
using namespace clang;
using namespace sema;
Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType) {
if (OwnedType) {
Decl *Group[2] = { OwnedType, Ptr };
return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, 2));
}
return DeclGroupPtrTy::make(DeclGroupRef(Ptr));
}
namespace {
class TypeNameValidatorCCC : public CorrectionCandidateCallback {
public:
TypeNameValidatorCCC(bool AllowInvalid, bool WantClass=false,
bool AllowTemplates=false)
: AllowInvalidDecl(AllowInvalid), WantClassName(WantClass),
AllowClassTemplates(AllowTemplates) {
WantExpressionKeywords = false;
WantCXXNamedCasts = false;
WantRemainingKeywords = false;
}
bool ValidateCandidate(const TypoCorrection &candidate) override {
if (NamedDecl *ND = candidate.getCorrectionDecl()) {
bool IsType = isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND);
bool AllowedTemplate = AllowClassTemplates && isa<ClassTemplateDecl>(ND);
return (IsType || AllowedTemplate) &&
(AllowInvalidDecl || !ND->isInvalidDecl());
}
return !WantClassName && candidate.isKeyword();
}
private:
bool AllowInvalidDecl;
bool WantClassName;
bool AllowClassTemplates;
};
}
/// \brief Determine whether the token kind starts a simple-type-specifier.
bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const {
switch (Kind) {
// FIXME: Take into account the current language when deciding whether a
// token kind is a valid type specifier
case tok::kw_short:
case tok::kw_long:
case tok::kw___int64:
case tok::kw___int128:
case tok::kw_signed:
case tok::kw_unsigned:
case tok::kw_void:
case tok::kw_char:
case tok::kw_int:
case tok::kw_half:
case tok::kw_float:
case tok::kw_double:
case tok::kw_wchar_t:
case tok::kw_bool:
case tok::kw___underlying_type:
case tok::kw___auto_type:
return true;
case tok::annot_typename:
case tok::kw_char16_t:
case tok::kw_char32_t:
case tok::kw_typeof:
case tok::annot_decltype:
case tok::kw_decltype:
return getLangOpts().CPlusPlus;
default:
break;
}
return false;
}
namespace {
enum class UnqualifiedTypeNameLookupResult {
NotFound,
FoundNonType,
FoundType
};
} // namespace
/// \brief Tries to perform unqualified lookup of the type decls in bases for
/// dependent class.
/// \return \a NotFound if no any decls is found, \a FoundNotType if found not a
/// type decl, \a FoundType if only type decls are found.
static UnqualifiedTypeNameLookupResult
lookupUnqualifiedTypeNameInBase(Sema &S, const IdentifierInfo &II,
SourceLocation NameLoc,
const CXXRecordDecl *RD) {
if (!RD->hasDefinition())
return UnqualifiedTypeNameLookupResult::NotFound;
// Look for type decls in base classes.
UnqualifiedTypeNameLookupResult FoundTypeDecl =
UnqualifiedTypeNameLookupResult::NotFound;
for (const auto &Base : RD->bases()) {
const CXXRecordDecl *BaseRD = nullptr;
if (auto *BaseTT = Base.getType()->getAs<TagType>())
BaseRD = BaseTT->getAsCXXRecordDecl();
else if (auto *TST = Base.getType()->getAs<TemplateSpecializationType>()) {
// Look for type decls in dependent base classes that have known primary
// templates.
if (!TST || !TST->isDependentType())
continue;
auto *TD = TST->getTemplateName().getAsTemplateDecl();
if (!TD)
continue;
auto *BasePrimaryTemplate =
dyn_cast_or_null<CXXRecordDecl>(TD->getTemplatedDecl());
if (!BasePrimaryTemplate)
continue;
BaseRD = BasePrimaryTemplate;
}
if (BaseRD) {
for (NamedDecl *ND : BaseRD->lookup(&II)) {
if (!isa<TypeDecl>(ND))
return UnqualifiedTypeNameLookupResult::FoundNonType;
FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
}
if (FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound) {
switch (lookupUnqualifiedTypeNameInBase(S, II, NameLoc, BaseRD)) {
case UnqualifiedTypeNameLookupResult::FoundNonType:
return UnqualifiedTypeNameLookupResult::FoundNonType;
case UnqualifiedTypeNameLookupResult::FoundType:
FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
break;
case UnqualifiedTypeNameLookupResult::NotFound:
break;
}
}
}
}
return FoundTypeDecl;
}
static ParsedType recoverFromTypeInKnownDependentBase(Sema &S,
const IdentifierInfo &II,
SourceLocation NameLoc) {
// Lookup in the parent class template context, if any.
const CXXRecordDecl *RD = nullptr;
UnqualifiedTypeNameLookupResult FoundTypeDecl =
UnqualifiedTypeNameLookupResult::NotFound;
for (DeclContext *DC = S.CurContext;
DC && FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound;
DC = DC->getParent()) {
// Look for type decls in dependent base classes that have known primary
// templates.
RD = dyn_cast<CXXRecordDecl>(DC);
if (RD && RD->getDescribedClassTemplate())
FoundTypeDecl = lookupUnqualifiedTypeNameInBase(S, II, NameLoc, RD);
}
if (FoundTypeDecl != UnqualifiedTypeNameLookupResult::FoundType)
return ParsedType();
// We found some types in dependent base classes. Recover as if the user
// wrote 'typename MyClass::II' instead of 'II'. We'll fully resolve the
// lookup during template instantiation.
S.Diag(NameLoc, diag::ext_found_via_dependent_bases_lookup) << &II;
ASTContext &Context = S.Context;
auto *NNS = NestedNameSpecifier::Create(Context, nullptr, false,
cast<Type>(Context.getRecordType(RD)));
QualType T = Context.getDependentNameType(ETK_Typename, NNS, &II);
CXXScopeSpec SS;
SS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
TypeLocBuilder Builder;
DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
DepTL.setNameLoc(NameLoc);
DepTL.setElaboratedKeywordLoc(SourceLocation());
DepTL.setQualifierLoc(SS.getWithLocInContext(Context));
return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
}
/// \brief If the identifier refers to a type name within this scope,
/// return the declaration of that type.
///
/// This routine performs ordinary name lookup of the identifier II
/// within the given scope, with optional C++ scope specifier SS, to
/// determine whether the name refers to a type. If so, returns an
/// opaque pointer (actually a QualType) corresponding to that
/// type. Otherwise, returns NULL.
ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
Scope *S, CXXScopeSpec *SS,
bool isClassName, bool HasTrailingDot,
ParsedType ObjectTypePtr,
bool IsCtorOrDtorName,
bool WantNontrivialTypeSourceInfo,
IdentifierInfo **CorrectedII) {
// Determine where we will perform name lookup.
DeclContext *LookupCtx = nullptr;
if (ObjectTypePtr) {
QualType ObjectType = ObjectTypePtr.get();
if (ObjectType->isRecordType())
LookupCtx = computeDeclContext(ObjectType);
} else if (SS && SS->isNotEmpty()) {
LookupCtx = computeDeclContext(*SS, false);
if (!LookupCtx) {
if (isDependentScopeSpecifier(*SS)) {
// C++ [temp.res]p3:
// A qualified-id that refers to a type and in which the
// nested-name-specifier depends on a template-parameter (14.6.2)
// shall be prefixed by the keyword typename to indicate that the
// qualified-id denotes a type, forming an
// elaborated-type-specifier (7.1.5.3).
//
// We therefore do not perform any name lookup if the result would
// refer to a member of an unknown specialization.
if (!isClassName && !IsCtorOrDtorName)
return ParsedType();
// We know from the grammar that this name refers to a type,
// so build a dependent node to describe the type.
if (WantNontrivialTypeSourceInfo)
return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get();
NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context);
QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc,
II, NameLoc);
return ParsedType::make(T);
}
return ParsedType();
}
if (!LookupCtx->isDependentContext() &&
RequireCompleteDeclContext(*SS, LookupCtx))
return ParsedType();
}
// FIXME: LookupNestedNameSpecifierName isn't the right kind of
// lookup for class-names.
LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName :
LookupOrdinaryName;
LookupResult Result(*this, &II, NameLoc, Kind);
if (LookupCtx) {
// Perform "qualified" name lookup into the declaration context we
// computed, which is either the type of the base of a member access
// expression or the declaration context associated with a prior
// nested-name-specifier.
LookupQualifiedName(Result, LookupCtx);
if (ObjectTypePtr && Result.empty()) {
// C++ [basic.lookup.classref]p3:
// If the unqualified-id is ~type-name, the type-name is looked up
// in the context of the entire postfix-expression. If the type T of
// the object expression is of a class type C, the type-name is also
// looked up in the scope of class C. At least one of the lookups shall
// find a name that refers to (possibly cv-qualified) T.
LookupName(Result, S);
}
} else {
// Perform unqualified name lookup.
LookupName(Result, S);
// For unqualified lookup in a class template in MSVC mode, look into
// dependent base classes where the primary class template is known.
if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) {
if (ParsedType TypeInBase =
recoverFromTypeInKnownDependentBase(*this, II, NameLoc))
return TypeInBase;
}
}
NamedDecl *IIDecl = nullptr;
switch (Result.getResultKind()) {
case LookupResult::NotFound:
case LookupResult::NotFoundInCurrentInstantiation:
if (CorrectedII) {
TypoCorrection Correction = CorrectTypo(
Result.getLookupNameInfo(), Kind, S, SS,
llvm::make_unique<TypeNameValidatorCCC>(true, isClassName),
CTK_ErrorRecovery);
IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo();
TemplateTy Template;
bool MemberOfUnknownSpecialization;
UnqualifiedId TemplateName;
TemplateName.setIdentifier(NewII, NameLoc);
NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier();
CXXScopeSpec NewSS, *NewSSPtr = SS;
if (SS && NNS) {
NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
NewSSPtr = &NewSS;
}
if (Correction && (NNS || NewII != &II) &&
// Ignore a correction to a template type as the to-be-corrected
// identifier is not a template (typo correction for template names
// is handled elsewhere).
!(getLangOpts().CPlusPlus && NewSSPtr &&
isTemplateName(S, *NewSSPtr, false, TemplateName, ParsedType(),
false, Template, MemberOfUnknownSpecialization))) {
ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr,
isClassName, HasTrailingDot, ObjectTypePtr,
IsCtorOrDtorName,
WantNontrivialTypeSourceInfo);
if (Ty) {
diagnoseTypo(Correction,
PDiag(diag::err_unknown_type_or_class_name_suggest)
<< Result.getLookupName() << isClassName);
if (SS && NNS)
SS->MakeTrivial(Context, NNS, SourceRange(NameLoc));
*CorrectedII = NewII;
return Ty;
}
}
}
// If typo correction failed or was not performed, fall through
case LookupResult::FoundOverloaded:
case LookupResult::FoundUnresolvedValue:
Result.suppressDiagnostics();
return ParsedType();
case LookupResult::Ambiguous:
// Recover from type-hiding ambiguities by hiding the type. We'll
// do the lookup again when looking for an object, and we can
// diagnose the error then. If we don't do this, then the error
// about hiding the type will be immediately followed by an error
// that only makes sense if the identifier was treated like a type.
if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) {
Result.suppressDiagnostics();
return ParsedType();
}
// Look to see if we have a type anywhere in the list of results.
for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end();
Res != ResEnd; ++Res) {
if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) {
if (!IIDecl ||
(*Res)->getLocation().getRawEncoding() <
IIDecl->getLocation().getRawEncoding())
IIDecl = *Res;
}
}
if (!IIDecl) {
// None of the entities we found is a type, so there is no way
// to even assume that the result is a type. In this case, don't
// complain about the ambiguity. The parser will either try to
// perform this lookup again (e.g., as an object name), which
// will produce the ambiguity, or will complain that it expected
// a type name.
Result.suppressDiagnostics();
return ParsedType();
}
// We found a type within the ambiguous lookup; diagnose the
// ambiguity and then return that type. This might be the right
// answer, or it might not be, but it suppresses any attempt to
// perform the name lookup again.
break;
case LookupResult::Found:
IIDecl = Result.getFoundDecl();
break;
}
assert(IIDecl && "Didn't find decl");
QualType T;
if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) {
DiagnoseUseOfDecl(IIDecl, NameLoc);
T = Context.getTypeDeclType(TD);
MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
// NOTE: avoid constructing an ElaboratedType(Loc) if this is a
// constructor or destructor name (in such a case, the scope specifier
// will be attached to the enclosing Expr or Decl node).
if (SS && SS->isNotEmpty() && !IsCtorOrDtorName) {
if (WantNontrivialTypeSourceInfo) {
// Construct a type with type-source information.
TypeLocBuilder Builder;
Builder.pushTypeSpec(T).setNameLoc(NameLoc);
T = getElaboratedType(ETK_None, *SS, T);
ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
ElabTL.setElaboratedKeywordLoc(SourceLocation());
ElabTL.setQualifierLoc(SS->getWithLocInContext(Context));
return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
} else {
T = getElaboratedType(ETK_None, *SS, T);
}
}
} else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
(void)DiagnoseUseOfDecl(IDecl, NameLoc);
if (!HasTrailingDot)
T = Context.getObjCInterfaceType(IDecl);
}
if (T.isNull()) {
// If it's not plausibly a type, suppress diagnostics.
Result.suppressDiagnostics();
return ParsedType();
}
return ParsedType::make(T);
}
// Builds a fake NNS for the given decl context.
static NestedNameSpecifier *
synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) {
for (;; DC = DC->getLookupParent()) {
DC = DC->getPrimaryContext();
auto *ND = dyn_cast<NamespaceDecl>(DC);
if (ND && !ND->isInline() && !ND->isAnonymousNamespace())
return NestedNameSpecifier::Create(Context, nullptr, ND);
else if (auto *RD = dyn_cast<CXXRecordDecl>(DC))
return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
RD->getTypeForDecl());
else if (isa<TranslationUnitDecl>(DC))
return NestedNameSpecifier::GlobalSpecifier(Context);
}
llvm_unreachable("something isn't in TU scope?");
}
ParsedType Sema::ActOnDelayedDefaultTemplateArg(const IdentifierInfo &II,
SourceLocation NameLoc) {
// Accepting an undeclared identifier as a default argument for a template
// type parameter is a Microsoft extension.
Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
// Build a fake DependentNameType that will perform lookup into CurContext at
// instantiation time. The name specifier isn't dependent, so template
// instantiation won't transform it. It will retry the lookup, however.
NestedNameSpecifier *NNS =
synthesizeCurrentNestedNameSpecifier(Context, CurContext);
QualType T = Context.getDependentNameType(ETK_None, NNS, &II);
// Build type location information. We synthesized the qualifier, so we have
// to build a fake NestedNameSpecifierLoc.
NestedNameSpecifierLocBuilder NNSLocBuilder;
NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc));
NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context);
TypeLocBuilder Builder;
DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
DepTL.setNameLoc(NameLoc);
DepTL.setElaboratedKeywordLoc(SourceLocation());
DepTL.setQualifierLoc(QualifierLoc);
return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
}
/// isTagName() - This method is called *for error recovery purposes only*
/// to determine if the specified name is a valid tag name ("struct foo"). If
/// so, this returns the TST for the tag corresponding to it (TST_enum,
/// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose
/// cases in C where the user forgot to specify the tag.
DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) {
// Do a tag name lookup in this scope.
LookupResult R(*this, &II, SourceLocation(), LookupTagName);
LookupName(R, S, false);
R.suppressDiagnostics();
if (R.getResultKind() == LookupResult::Found)
if (const TagDecl *TD = R.getAsSingle<TagDecl>()) {
switch (TD->getTagKind()) {
case TTK_Struct: return DeclSpec::TST_struct;
case TTK_Interface: return DeclSpec::TST_interface;
case TTK_Union: return DeclSpec::TST_union;
case TTK_Class: return DeclSpec::TST_class;
case TTK_Enum: return DeclSpec::TST_enum;
}
}
return DeclSpec::TST_unspecified;
}
/// isMicrosoftMissingTypename - In Microsoft mode, within class scope,
/// if a CXXScopeSpec's type is equal to the type of one of the base classes
/// then downgrade the missing typename error to a warning.
/// This is needed for MSVC compatibility; Example:
/// @code
/// template<class T> class A {
/// public:
/// typedef int TYPE;
/// };
/// template<class T> class B : public A<T> {
/// public:
/// A<T>::TYPE a; // no typename required because A<T> is a base class.
/// };
/// @endcode
bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) {
if (CurContext->isRecord()) {
if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super)
return true;
const Type *Ty = SS->getScopeRep()->getAsType();
CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext);
for (const auto &Base : RD->bases())
if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType()))
return true;
return S->isFunctionPrototypeScope();
}
return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope();
}
void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II,
SourceLocation IILoc,
Scope *S,
CXXScopeSpec *SS,
ParsedType &SuggestedType,
bool AllowClassTemplates) {
// We don't have anything to suggest (yet).
SuggestedType = ParsedType();
// There may have been a typo in the name of the type. Look up typo
// results, in case we have something that we can suggest.
if (TypoCorrection Corrected =
CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS,
llvm::make_unique<TypeNameValidatorCCC>(
false, false, AllowClassTemplates),
CTK_ErrorRecovery)) {
if (Corrected.isKeyword()) {
// We corrected to a keyword.
diagnoseTypo(Corrected, PDiag(diag::err_unknown_typename_suggest) << II);
II = Corrected.getCorrectionAsIdentifierInfo();
} else {
// We found a similarly-named type or interface; suggest that.
if (!SS || !SS->isSet()) {
diagnoseTypo(Corrected,
PDiag(diag::err_unknown_typename_suggest) << II);
} else if (DeclContext *DC = computeDeclContext(*SS, false)) {
std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
II->getName().equals(CorrectedStr);
diagnoseTypo(Corrected,
PDiag(diag::err_unknown_nested_typename_suggest)
<< II << DC << DroppedSpecifier << SS->getRange());
} else {
llvm_unreachable("could not have corrected a typo here");
}
CXXScopeSpec tmpSS;
if (Corrected.getCorrectionSpecifier())
tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
SourceRange(IILoc));
SuggestedType = getTypeName(*Corrected.getCorrectionAsIdentifierInfo(),
IILoc, S, tmpSS.isSet() ? &tmpSS : SS, false,
false, ParsedType(),
/*IsCtorOrDtorName=*/false,
/*NonTrivialTypeSourceInfo=*/true);
}
return;
}
if (getLangOpts().CPlusPlus) {
// See if II is a class template that the user forgot to pass arguments to.
UnqualifiedId Name;
Name.setIdentifier(II, IILoc);
CXXScopeSpec EmptySS;
TemplateTy TemplateResult;
bool MemberOfUnknownSpecialization;
if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false,
Name, ParsedType(), true, TemplateResult,
MemberOfUnknownSpecialization) == TNK_Type_template) {
TemplateName TplName = TemplateResult.get();
Diag(IILoc, diag::err_template_missing_args) << TplName;
if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) {
Diag(TplDecl->getLocation(), diag::note_template_decl_here)
<< TplDecl->getTemplateParameters()->getSourceRange();
}
return;
}
}
// FIXME: Should we move the logic that tries to recover from a missing tag
// (struct, union, enum) from Parser::ParseImplicitInt here, instead?
if (!SS || (!SS->isSet() && !SS->isInvalid()))
Diag(IILoc, diag::err_unknown_typename) << II;
else if (DeclContext *DC = computeDeclContext(*SS, false))
Diag(IILoc, diag::err_typename_nested_not_found)
<< II << DC << SS->getRange();
else if (isDependentScopeSpecifier(*SS)) {
unsigned DiagID = diag::err_typename_missing;
if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S))
DiagID = diag::ext_typename_missing;
Diag(SS->getRange().getBegin(), DiagID)
<< SS->getScopeRep() << II->getName()
<< SourceRange(SS->getRange().getBegin(), IILoc)
<< FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename ");
SuggestedType = ActOnTypenameType(S, SourceLocation(),
*SS, *II, IILoc).get();
} else {
assert(SS && SS->isInvalid() &&
"Invalid scope specifier has already been diagnosed");
}
}
/// \brief Determine whether the given result set contains either a type name
/// or
static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) {
bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus &&
NextToken.is(tok::less);
for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I))
return true;
if (CheckTemplate && isa<TemplateDecl>(*I))
return true;
}
return false;
}
static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result,
Scope *S, CXXScopeSpec &SS,
IdentifierInfo *&Name,
SourceLocation NameLoc) {
LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName);
SemaRef.LookupParsedName(R, S, &SS);
if (TagDecl *Tag = R.getAsSingle<TagDecl>()) {
StringRef FixItTagName;
switch (Tag->getTagKind()) {
case TTK_Class:
FixItTagName = "class ";
break;
case TTK_Enum:
FixItTagName = "enum ";
break;
case TTK_Struct:
FixItTagName = "struct ";
break;
case TTK_Interface:
FixItTagName = "__interface ";
break;
case TTK_Union:
FixItTagName = "union ";
break;
}
StringRef TagName = FixItTagName.drop_back();
SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag)
<< Name << TagName << SemaRef.getLangOpts().CPlusPlus
<< FixItHint::CreateInsertion(NameLoc, FixItTagName);
for (LookupResult::iterator I = Result.begin(), IEnd = Result.end();
I != IEnd; ++I)
SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
<< Name << TagName;
// Replace lookup results with just the tag decl.
Result.clear(Sema::LookupTagName);
SemaRef.LookupParsedName(Result, S, &SS);
return true;
}
return false;
}
/// Build a ParsedType for a simple-type-specifier with a nested-name-specifier.
static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS,
QualType T, SourceLocation NameLoc) {
ASTContext &Context = S.Context;
TypeLocBuilder Builder;
Builder.pushTypeSpec(T).setNameLoc(NameLoc);
T = S.getElaboratedType(ETK_None, SS, T);
ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
ElabTL.setElaboratedKeywordLoc(SourceLocation());
ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
}
Sema::NameClassification
Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
SourceLocation NameLoc, const Token &NextToken,
bool IsAddressOfOperand,
std::unique_ptr<CorrectionCandidateCallback> CCC) {
DeclarationNameInfo NameInfo(Name, NameLoc);
ObjCMethodDecl *CurMethod = getCurMethodDecl();
if (NextToken.is(tok::coloncolon)) {
BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(),
QualType(), false, SS, nullptr, false);
}
LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
LookupParsedName(Result, S, &SS, !CurMethod);
// For unqualified lookup in a class template in MSVC mode, look into
// dependent base classes where the primary class template is known.
if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) {
if (ParsedType TypeInBase =
recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc))
return TypeInBase;
}
// Perform lookup for Objective-C instance variables (including automatically
// synthesized instance variables), if we're in an Objective-C method.
// FIXME: This lookup really, really needs to be folded in to the normal
// unqualified lookup mechanism.
if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) {
ExprResult E = LookupInObjCMethod(Result, S, Name, true);
if (E.get() || E.isInvalid())
return E;
}
bool SecondTry = false;
bool IsFilteredTemplateName = false;
Corrected:
switch (Result.getResultKind()) {
case LookupResult::NotFound:
// If an unqualified-id is followed by a '(', then we have a function
// call.
if (!SS.isSet() && NextToken.is(tok::l_paren)) {
// In C++, this is an ADL-only call.
// FIXME: Reference?
if (getLangOpts().CPlusPlus)
return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true);
// C90 6.3.2.2:
// If the expression that precedes the parenthesized argument list in a
// function call consists solely of an identifier, and if no
// declaration is visible for this identifier, the identifier is
// implicitly declared exactly as if, in the innermost block containing
// the function call, the declaration
//
// extern int identifier ();
//
// appeared.
//
// We also allow this in C99 as an extension.
if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) {
Result.addDecl(D);
Result.resolveKind();
return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false);
}
}
// In C, we first see whether there is a tag type by the same name, in
// which case it's likely that the user just forget to write "enum",
// "struct", or "union".
if (!getLangOpts().CPlusPlus && !SecondTry &&
isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
break;
}
// Perform typo correction to determine if there is another name that is
// close to this name.
if (!SecondTry && CCC) {
SecondTry = true;
if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(),
Result.getLookupKind(), S,
&SS, std::move(CCC),
CTK_ErrorRecovery)) {
unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
unsigned QualifiedDiag = diag::err_no_member_suggest;
NamedDecl *FirstDecl = Corrected.getCorrectionDecl();
NamedDecl *UnderlyingFirstDecl
= FirstDecl? FirstDecl->getUnderlyingDecl() : nullptr;
if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
UnqualifiedDiag = diag::err_no_template_suggest;
QualifiedDiag = diag::err_no_member_template_suggest;
} else if (UnderlyingFirstDecl &&
(isa<TypeDecl>(UnderlyingFirstDecl) ||
isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) ||
isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) {
UnqualifiedDiag = diag::err_unknown_typename_suggest;
QualifiedDiag = diag::err_unknown_nested_typename_suggest;
}
if (SS.isEmpty()) {
diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name);
} else {// FIXME: is this even reachable? Test it.
std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
Name->getName().equals(CorrectedStr);
diagnoseTypo(Corrected, PDiag(QualifiedDiag)
<< Name << computeDeclContext(SS, false)
<< DroppedSpecifier << SS.getRange());
}
// Update the name, so that the caller has the new name.
Name = Corrected.getCorrectionAsIdentifierInfo();
// Typo correction corrected to a keyword.
if (Corrected.isKeyword())
return Name;
// Also update the LookupResult...
// FIXME: This should probably go away at some point
Result.clear();
Result.setLookupName(Corrected.getCorrection());
if (FirstDecl)
Result.addDecl(FirstDecl);
// If we found an Objective-C instance variable, let
// LookupInObjCMethod build the appropriate expression to
// reference the ivar.
// FIXME: This is a gross hack.
if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) {
Result.clear();
ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier()));
return E;
}
goto Corrected;
}
}
// We failed to correct; just fall through and let the parser deal with it.
Result.suppressDiagnostics();
return NameClassification::Unknown();
case LookupResult::NotFoundInCurrentInstantiation: {
// We performed name lookup into the current instantiation, and there were
// dependent bases, so we treat this result the same way as any other
// dependent nested-name-specifier.
// C++ [temp.res]p2:
// A name used in a template declaration or definition and that is
// dependent on a template-parameter is assumed not to name a type
// unless the applicable name lookup finds a type name or the name is
// qualified by the keyword typename.
//
// FIXME: If the next token is '<', we might want to ask the parser to
// perform some heroics to see if we actually have a
// template-argument-list, which would indicate a missing 'template'
// keyword here.
return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(),
NameInfo, IsAddressOfOperand,
/*TemplateArgs=*/nullptr);
}
case LookupResult::Found:
case LookupResult::FoundOverloaded:
case LookupResult::FoundUnresolvedValue:
break;
case LookupResult::Ambiguous:
if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
hasAnyAcceptableTemplateNames(Result)) {
// C++ [temp.local]p3:
// A lookup that finds an injected-class-name (10.2) can result in an
// ambiguity in certain cases (for example, if it is found in more than
// one base class). If all of the injected-class-names that are found
// refer to specializations of the same class template, and if the name
// is followed by a template-argument-list, the reference refers to the
// class template itself and not a specialization thereof, and is not
// ambiguous.
//
// This filtering can make an ambiguous result into an unambiguous one,
// so try again after filtering out template names.
FilterAcceptableTemplateNames(Result);
if (!Result.isAmbiguous()) {
IsFilteredTemplateName = true;
break;
}
}
// Diagnose the ambiguity and return an error.
return NameClassification::Error();
}
if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
(IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) {
// C++ [temp.names]p3:
// After name lookup (3.4) finds that a name is a template-name or that
// an operator-function-id or a literal- operator-id refers to a set of
// overloaded functions any member of which is a function template if
// this is followed by a <, the < is always taken as the delimiter of a
// template-argument-list and never as the less-than operator.
if (!IsFilteredTemplateName)
FilterAcceptableTemplateNames(Result);
if (!Result.empty()) {
bool IsFunctionTemplate;
bool IsVarTemplate;
TemplateName Template;
if (Result.end() - Result.begin() > 1) {
IsFunctionTemplate = true;
Template = Context.getOverloadedTemplateName(Result.begin(),
Result.end());
} else {
TemplateDecl *TD
= cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl());
IsFunctionTemplate = isa<FunctionTemplateDecl>(TD);
IsVarTemplate = isa<VarTemplateDecl>(TD);
if (SS.isSet() && !SS.isInvalid())
Template = Context.getQualifiedTemplateName(SS.getScopeRep(),
/*TemplateKeyword=*/false,
TD);
else
Template = TemplateName(TD);
}
if (IsFunctionTemplate) {
// Function templates always go through overload resolution, at which
// point we'll perform the various checks (e.g., accessibility) we need
// to based on which function we selected.
Result.suppressDiagnostics();
return NameClassification::FunctionTemplate(Template);
}
return IsVarTemplate ? NameClassification::VarTemplate(Template)
: NameClassification::TypeTemplate(Template);
}
}
NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl();
if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) {
DiagnoseUseOfDecl(Type, NameLoc);
MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
QualType T = Context.getTypeDeclType(Type);
if (SS.isNotEmpty())
return buildNestedType(*this, SS, T, NameLoc);
return ParsedType::make(T);
}
ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl);
if (!Class) {
// FIXME: It's unfortunate that we don't have a Type node for handling this.
if (ObjCCompatibleAliasDecl *Alias =
dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl))
Class = Alias->getClassInterface();
}
if (Class) {
DiagnoseUseOfDecl(Class, NameLoc);
if (NextToken.is(tok::period)) {
// Interface. <something> is parsed as a property reference expression.
// Just return "unknown" as a fall-through for now.
Result.suppressDiagnostics();
return NameClassification::Unknown();
}
QualType T = Context.getObjCInterfaceType(Class);
return ParsedType::make(T);
}
// We can have a type template here if we're classifying a template argument.
if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl))
return NameClassification::TypeTemplate(
TemplateName(cast<TemplateDecl>(FirstDecl)));
// Check for a tag type hidden by a non-type decl in a few cases where it
// seems likely a type is wanted instead of the non-type that was found.
bool NextIsOp = NextToken.isOneOf(tok::amp, tok::star);
if ((NextToken.is(tok::identifier) ||
(NextIsOp &&
FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) &&
isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
TypeDecl *Type = Result.getAsSingle<TypeDecl>();
DiagnoseUseOfDecl(Type, NameLoc);
QualType T = Context.getTypeDeclType(Type);
if (SS.isNotEmpty())
return buildNestedType(*this, SS, T, NameLoc);
return ParsedType::make(T);
}
if (FirstDecl->isCXXClassMember())
return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result,
nullptr, S);
bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren));
return BuildDeclarationNameExpr(SS, Result, ADL);
}
// Determines the context to return to after temporarily entering a
// context. This depends in an unnecessarily complicated way on the
// exact ordering of callbacks from the parser.
DeclContext *Sema::getContainingDC(DeclContext *DC) {
// Functions defined inline within classes aren't parsed until we've
// finished parsing the top-level class, so the top-level class is
// the context we'll need to return to.
// A Lambda call operator whose parent is a class must not be treated
// as an inline member function. A Lambda can be used legally
// either as an in-class member initializer or a default argument. These
// are parsed once the class has been marked complete and so the containing
// context would be the nested class (when the lambda is defined in one);
// If the class is not complete, then the lambda is being used in an
// ill-formed fashion (such as to specify the width of a bit-field, or
// in an array-bound) - in which case we still want to return the
// lexically containing DC (which could be a nested class).
if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(DC)) {
DC = DC->getLexicalParent();
// A function not defined within a class will always return to its
// lexical context.
if (!isa<CXXRecordDecl>(DC))
return DC;
// A C++ inline method/friend is parsed *after* the topmost class
// it was declared in is fully parsed ("complete"); the topmost
// class is the context we need to return to.
while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
DC = RD;
// Return the declaration context of the topmost class the inline method is
// declared in.
return DC;
}
return DC->getLexicalParent();
}
void Sema::PushDeclContext(Scope *S, DeclContext *DC) {
assert(getContainingDC(DC) == CurContext &&
"The next DeclContext should be lexically contained in the current one.");
CurContext = DC;
S->setEntity(DC);
}
void Sema::PopDeclContext() {
assert(CurContext && "DeclContext imbalance!");
CurContext = getContainingDC(CurContext);
assert(CurContext && "Popped translation unit!");
}
Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S,
Decl *D) {
// Unlike PushDeclContext, the context to which we return is not necessarily
// the containing DC of TD, because the new context will be some pre-existing
// TagDecl definition instead of a fresh one.
auto Result = static_cast<SkippedDefinitionContext>(CurContext);
CurContext = cast<TagDecl>(D)->getDefinition();
assert(CurContext && "skipping definition of undefined tag");
// Start lookups from the parent of the current context; we don't want to look
// into the pre-existing complete definition.
S->setEntity(CurContext->getLookupParent());
return Result;
}
void Sema::ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context) {
CurContext = static_cast<decltype(CurContext)>(Context);
}
/// EnterDeclaratorContext - Used when we must lookup names in the context
/// of a declarator's nested name specifier.
///
void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) {
// C++0x [basic.lookup.unqual]p13:
// A name used in the definition of a static data member of class
// X (after the qualified-id of the static member) is looked up as
// if the name was used in a member function of X.
// C++0x [basic.lookup.unqual]p14:
// If a variable member of a namespace is defined outside of the
// scope of its namespace then any name used in the definition of
// the variable member (after the declarator-id) is looked up as
// if the definition of the variable member occurred in its
// namespace.
// Both of these imply that we should push a scope whose context
// is the semantic context of the declaration. We can't use
// PushDeclContext here because that context is not necessarily
// lexically contained in the current context. Fortunately,
// the containing scope should have the appropriate information.
assert(!S->getEntity() && "scope already has entity");
#ifndef NDEBUG
Scope *Ancestor = S->getParent();
while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch");
#endif
CurContext = DC;
S->setEntity(DC);
}
void Sema::ExitDeclaratorContext(Scope *S) {
assert(S->getEntity() == CurContext && "Context imbalance!");
// Switch back to the lexical context. The safety of this is
// enforced by an assert in EnterDeclaratorContext.
Scope *Ancestor = S->getParent();
while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
CurContext = Ancestor->getEntity();
// We don't need to do anything with the scope, which is going to
// disappear.
}
void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
// We assume that the caller has already called
// ActOnReenterTemplateScope so getTemplatedDecl() works.
FunctionDecl *FD = D->getAsFunction();
if (!FD)
return;
// Same implementation as PushDeclContext, but enters the context
// from the lexical parent, rather than the top-level class.
assert(CurContext == FD->getLexicalParent() &&
"The next DeclContext should be lexically contained in the current one.");
CurContext = FD;
S->setEntity(CurContext);
for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
ParmVarDecl *Param = FD->getParamDecl(P);
// If the parameter has an identifier, then add it to the scope
if (Param->getIdentifier()) {
S->AddDecl(Param);
IdResolver.AddDecl(Param);
}
}
}
void Sema::ActOnExitFunctionContext() {
// Same implementation as PopDeclContext, but returns to the lexical parent,
// rather than the top-level class.
assert(CurContext && "DeclContext imbalance!");
CurContext = CurContext->getLexicalParent();
assert(CurContext && "Popped translation unit!");
}
/// \brief Determine whether we allow overloading of the function
/// PrevDecl with another declaration.
///
/// This routine determines whether overloading is possible, not
/// whether some new function is actually an overload. It will return
/// true in C++ (where we can always provide overloads) or, as an
/// extension, in C when the previous function is already an
/// overloaded function declaration or has the "overloadable"
/// attribute.
static bool AllowOverloadingOfFunction(LookupResult &Previous,
ASTContext &Context) {
if (Context.getLangOpts().CPlusPlus)
return true;
if (Previous.getResultKind() == LookupResult::FoundOverloaded)
return true;
return (Previous.getResultKind() == LookupResult::Found
&& Previous.getFoundDecl()->hasAttr<OverloadableAttr>());
}
/// Add this decl to the scope shadowed decl chains.
void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) {
// Move up the scope chain until we find the nearest enclosing
// non-transparent context. The declaration will be introduced into this
// scope.
while (S->getEntity() && S->getEntity()->isTransparentContext())
S = S->getParent();
// Add scoped declarations into their context, so that they can be
// found later. Declarations without a context won't be inserted
// into any context.
if (AddToContext)
CurContext->addDecl(D);
// Out-of-line definitions shouldn't be pushed into scope in C++, unless they
// are function-local declarations.
if (getLangOpts().CPlusPlus && D->isOutOfLine() &&
!D->getDeclContext()->getRedeclContext()->Equals(
D->getLexicalDeclContext()->getRedeclContext()) &&
!D->getLexicalDeclContext()->isFunctionOrMethod())
return;
// Template instantiations should also not be pushed into scope.
if (isa<FunctionDecl>(D) &&
cast<FunctionDecl>(D)->isFunctionTemplateSpecialization())
return;
// If this replaces anything in the current scope,
IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()),
IEnd = IdResolver.end();
for (; I != IEnd; ++I) {
if (S->isDeclScope(*I) && D->declarationReplaces(*I)) {
S->RemoveDecl(*I);
IdResolver.RemoveDecl(*I);
// Should only need to replace one decl.
break;
}
}
S->AddDecl(D);
if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
// Implicitly-generated labels may end up getting generated in an order that
// isn't strictly lexical, which breaks name lookup. Be careful to insert
// the label at the appropriate place in the identifier chain.
for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext();
if (IDC == CurContext) {
if (!S->isDeclScope(*I))
continue;
} else if (IDC->Encloses(CurContext))
break;
}
IdResolver.InsertDeclAfter(I, D);
} else {
IdResolver.AddDecl(D);
}
}
void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) {
if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope)
TUScope->AddDecl(D);
}
bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S,
bool AllowInlineNamespace) {
return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace);
}
Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) {
DeclContext *TargetDC = DC->getPrimaryContext();
do {
if (DeclContext *ScopeDC = S->getEntity())
if (ScopeDC->getPrimaryContext() == TargetDC)
return S;
} while ((S = S->getParent()));
return nullptr;
}
static bool isOutOfScopePreviousDeclaration(NamedDecl *,
DeclContext*,
ASTContext&);
/// Filters out lookup results that don't fall within the given scope
/// as determined by isDeclInScope.
void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
bool ConsiderLinkage,
bool AllowInlineNamespace) {
LookupResult::Filter F = R.makeFilter();
while (F.hasNext()) {
NamedDecl *D = F.next();
if (isDeclInScope(D, Ctx, S, AllowInlineNamespace))
continue;
if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context))
continue;
F.erase();
}
F.done();
}
static bool isUsingDecl(NamedDecl *D) {
return isa<UsingShadowDecl>(D) ||
isa<UnresolvedUsingTypenameDecl>(D) ||
isa<UnresolvedUsingValueDecl>(D);
}
/// Removes using shadow declarations from the lookup results.
static void RemoveUsingDecls(LookupResult &R) {
LookupResult::Filter F = R.makeFilter();
while (F.hasNext())
if (isUsingDecl(F.next()))
F.erase();
F.done();
}
/// \brief Check for this common pattern:
/// @code
/// class S {
/// S(const S&); // DO NOT IMPLEMENT
/// void operator=(const S&); // DO NOT IMPLEMENT
/// };
/// @endcode
static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) {
// FIXME: Should check for private access too but access is set after we get
// the decl here.
if (D->doesThisDeclarationHaveABody())
return false;
if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
return CD->isCopyConstructor();
if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
return Method->isCopyAssignmentOperator();
return false;
}
// We need this to handle
//
// typedef struct {
// void *foo() { return 0; }
// } A;
//
// When we see foo we don't know if after the typedef we will get 'A' or '*A'
// for example. If 'A', foo will have external linkage. If we have '*A',
// foo will have no linkage. Since we can't know until we get to the end
// of the typedef, this function finds out if D might have non-external linkage.
// Callers should verify at the end of the TU if it D has external linkage or
// not.
bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) {
const DeclContext *DC = D->getDeclContext();
while (!DC->isTranslationUnit()) {
if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){
if (!RD->hasNameForLinkage())
return true;
}
DC = DC->getParent();
}
return !D->isExternallyVisible();
}
// FIXME: This needs to be refactored; some other isInMainFile users want
// these semantics.
static bool isMainFileLoc(const Sema &S, SourceLocation Loc) {
if (S.TUKind != TU_Complete)
return false;
return S.SourceMgr.isInMainFile(Loc);
}
bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
assert(D);
if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
return false;
// Ignore all entities declared within templates, and out-of-line definitions
// of members of class templates.
if (D->getDeclContext()->isDependentContext() ||
D->getLexicalDeclContext()->isDependentContext())
return false;
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
return false;
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD))
return false;
} else {
// 'static inline' functions are defined in headers; don't warn.
if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
return false;
}
if (FD->doesThisDeclarationHaveABody() &&
Context.DeclMustBeEmitted(FD))
return false;
} else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
// Constants and utility variables are defined in headers with internal
// linkage; don't warn. (Unlike functions, there isn't a convenient marker
// like "inline".)
if (!isMainFileLoc(*this, VD->getLocation()))
return false;
if (Context.DeclMustBeEmitted(VD))
return false;
if (VD->isStaticDataMember() &&
VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
return false;
} else {
return false;
}
// Only warn for unused decls internal to the translation unit.
// FIXME: This seems like a bogus check; it suppresses -Wunused-function
// for inline functions defined in the main source file, for instance.
return mightHaveNonExternalLinkage(D);
}
void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
if (!D)
return;
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
const FunctionDecl *First = FD->getFirstDecl();
if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
return; // First should already be in the vector.
}
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
const VarDecl *First = VD->getFirstDecl();
if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
return; // First should already be in the vector.
}
if (ShouldWarnIfUnusedFileScopedDecl(D))
UnusedFileScopedDecls.push_back(D);
}
static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
if (D->isInvalidDecl())
return false;
if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>() ||
D->hasAttr<ObjCPreciseLifetimeAttr>())
return false;
if (isa<LabelDecl>(D))
return true;
// Except for labels, we only care about unused decls that are local to
// functions.
bool WithinFunction = D->getDeclContext()->isFunctionOrMethod();
if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext()))
// For dependent types, the diagnostic is deferred.
WithinFunction =
WithinFunction || (R->isLocalClass() && !R->isDependentType());
if (!WithinFunction)
return false;
if (isa<TypedefNameDecl>(D))
return true;
// White-list anything that isn't a local variable.
if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D))
return false;
// Types of valid local variables should be complete, so this should succeed.
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
// White-list anything with an __attribute__((unused)) type.
QualType Ty = VD->getType();
// Only look at the outermost level of typedef.
if (const TypedefType *TT = Ty->getAs<TypedefType>()) {
if (TT->getDecl()->hasAttr<UnusedAttr>())
return false;
}
// If we failed to complete the type for some reason, or if the type is
// dependent, don't diagnose the variable.
if (Ty->isIncompleteType() || Ty->isDependentType())
return false;
if (const TagType *TT = Ty->getAs<TagType>()) {
const TagDecl *Tag = TT->getDecl();
if (Tag->hasAttr<UnusedAttr>())
return false;
if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) {
if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>())
return false;
if (const Expr *Init = VD->getInit()) {
if (const ExprWithCleanups *Cleanups =
dyn_cast<ExprWithCleanups>(Init))
Init = Cleanups->getSubExpr();
const CXXConstructExpr *Construct =
dyn_cast<CXXConstructExpr>(Init);
if (Construct && !Construct->isElidable()) {
CXXConstructorDecl *CD = Construct->getConstructor();
if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>())
return false;
}
}
}
}
// TODO: __attribute__((unused)) templates?
}
return true;
}
static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
FixItHint &Hint) {
if (isa<LabelDecl>(D)) {
SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(),
tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true);
if (AfterColon.isInvalid())
return;
Hint = FixItHint::CreateRemoval(CharSourceRange::
getCharRange(D->getLocStart(), AfterColon));
}
return;
}
void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) {
if (D->getTypeForDecl()->isDependentType())
return;
for (auto *TmpD : D->decls()) {
if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD))
DiagnoseUnusedDecl(T);
else if(const auto *R = dyn_cast<RecordDecl>(TmpD))
DiagnoseUnusedNestedTypedefs(R);
}
}
/// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
/// unless they are marked attr(unused).
void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
if (!ShouldDiagnoseUnusedDecl(D))
return;
if (auto *TD = dyn_cast<TypedefNameDecl>(D)) {
// typedefs can be referenced later on, so the diagnostics are emitted
// at end-of-translation-unit.
UnusedLocalTypedefNameCandidates.insert(TD);
return;
}
FixItHint Hint;
GenerateFixForUnusedDecl(D, Context, Hint);
unsigned DiagID;
if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
DiagID = diag::warn_unused_exception_param;
else if (isa<LabelDecl>(D))
DiagID = diag::warn_unused_label;
else
DiagID = diag::warn_unused_variable;
Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint;
}
static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
// Verify that we have no forward references left. If so, there was a goto
// or address of a label taken, but no definition of it. Label fwd
// definitions are indicated with a null substmt which is also not a resolved
// MS inline assembly label name.
bool Diagnose = false;
if (L->isMSAsmLabel())
Diagnose = !L->isResolvedMSAsmLabel();
else
Diagnose = L->getStmt() == nullptr;
if (Diagnose)
S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
}
void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
S->mergeNRVOIntoParent();
if (S->decl_empty()) return;
assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&
"Scope shouldn't contain decls!");
for (auto *TmpD : S->decls()) {
assert(TmpD && "This decl didn't get pushed??");
assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?");
NamedDecl *D = cast<NamedDecl>(TmpD);
if (!D->getDeclName()) continue;
// Diagnose unused variables in this scope.
if (!S->hasUnrecoverableErrorOccurred()) {
DiagnoseUnusedDecl(D);
if (const auto *RD = dyn_cast<RecordDecl>(D))
DiagnoseUnusedNestedTypedefs(RD);
}
// If this was a forward reference to a label, verify it was defined.
if (LabelDecl *LD = dyn_cast<LabelDecl>(D))
CheckPoppedLabel(LD, *this);
// Remove this name from our lexical scope.
IdResolver.RemoveDecl(D);
}
}
/// \brief Look for an Objective-C class in the translation unit.
///
/// \param Id The name of the Objective-C class we're looking for. If
/// typo-correction fixes this name, the Id will be updated
/// to the fixed name.
///
/// \param IdLoc The location of the name in the translation unit.
///
/// \param DoTypoCorrection If true, this routine will attempt typo correction
/// if there is no class with the given name.
///
/// \returns The declaration of the named Objective-C class, or NULL if the
/// class could not be found.
ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id,
SourceLocation IdLoc,
bool DoTypoCorrection) {
// The third "scope" argument is 0 since we aren't enabling lazy built-in
// creation from this context.
NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName);
if (!IDecl && DoTypoCorrection) {
// Perform typo correction at the given location, but only if we
// find an Objective-C class name.
if (TypoCorrection C = CorrectTypo(
DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, TUScope, nullptr,
llvm::make_unique<DeclFilterCCC<ObjCInterfaceDecl>>(),
CTK_ErrorRecovery)) {
diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id);
IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>();
Id = IDecl->getIdentifier();
}
}
ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl);
// This routine must always return a class definition, if any.
if (Def && Def->getDefinition())
Def = Def->getDefinition();
return Def;
}
/// getNonFieldDeclScope - Retrieves the innermost scope, starting
/// from S, where a non-field would be declared. This routine copes
/// with the difference between C and C++ scoping rules in structs and
/// unions. For example, the following code is well-formed in C but
/// ill-formed in C++:
/// @code
/// struct S6 {
/// enum { BAR } e;
/// };
///
/// void test_S6() {
/// struct S6 a;
/// a.e = BAR;
/// }
/// @endcode
/// For the declaration of BAR, this routine will return a different
/// scope. The scope S will be the scope of the unnamed enumeration
/// within S6. In C++, this routine will return the scope associated
/// with S6, because the enumeration's scope is a transparent
/// context but structures can contain non-field names. In C, this
/// routine will return the translation unit scope, since the
/// enumeration's scope is a transparent context and structures cannot
/// contain non-field names.
Scope *Sema::getNonFieldDeclScope(Scope *S) {
while (((S->getFlags() & Scope::DeclScope) == 0) ||
(S->getEntity() && S->getEntity()->isTransparentContext()) ||
(S->isClassScope() && !getLangOpts().CPlusPlus))
S = S->getParent();
return S;
}
/// \brief Looks up the declaration of "struct objc_super" and
/// saves it for later use in building builtin declaration of
/// objc_msgSendSuper and objc_msgSendSuper_stret. If no such
/// pre-existing declaration exists no action takes place.
static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S,
IdentifierInfo *II) {
if (!II->isStr("objc_msgSendSuper"))
return;
ASTContext &Context = ThisSema.Context;
LookupResult Result(ThisSema, &Context.Idents.get("objc_super"),
SourceLocation(), Sema::LookupTagName);
ThisSema.LookupName(Result, S);
if (Result.getResultKind() == LookupResult::Found)
if (const TagDecl *TD = Result.getAsSingle<TagDecl>())
Context.setObjCSuperType(Context.getTagDeclType(TD));
}
static StringRef getHeaderName(ASTContext::GetBuiltinTypeError Error) {
switch (Error) {
case ASTContext::GE_None:
return "";
case ASTContext::GE_Missing_stdio:
return "stdio.h";
case ASTContext::GE_Missing_setjmp:
return "setjmp.h";
case ASTContext::GE_Missing_ucontext:
return "ucontext.h";
}
llvm_unreachable("unhandled error kind");
}
/// LazilyCreateBuiltin - The specified Builtin-ID was first used at
/// file scope. lazily create a decl for it. ForRedeclaration is true
/// if we're creating this built-in in anticipation of redeclaring the
/// built-in.
NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
Scope *S, bool ForRedeclaration,
SourceLocation Loc) {
LookupPredefedObjCSuperType(*this, S, II);
ASTContext::GetBuiltinTypeError Error;
QualType R = Context.GetBuiltinType(ID, Error);
if (Error) {
if (ForRedeclaration)
Diag(Loc, diag::warn_implicit_decl_requires_sysheader)
<< getHeaderName(Error) << Context.BuiltinInfo.getName(ID);
return nullptr;
}
if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(ID)) {
Diag(Loc, diag::ext_implicit_lib_function_decl)
<< Context.BuiltinInfo.getName(ID) << R;
if (Context.BuiltinInfo.getHeaderName(ID) &&
!Diags.isIgnored(diag::ext_implicit_lib_function_decl, Loc))
Diag(Loc, diag::note_include_header_or_declare)
<< Context.BuiltinInfo.getHeaderName(ID)
<< Context.BuiltinInfo.getName(ID);
}
DeclContext *Parent = Context.getTranslationUnitDecl();
if (getLangOpts().CPlusPlus) {
LinkageSpecDecl *CLinkageDecl =
LinkageSpecDecl::Create(Context, Parent, Loc, Loc,
LinkageSpecDecl::lang_c, false);
CLinkageDecl->setImplicit();
Parent->addDecl(CLinkageDecl);
Parent = CLinkageDecl;
}
FunctionDecl *New = FunctionDecl::Create(Context,
Parent,
Loc, Loc, II, R, /*TInfo=*/nullptr,
SC_Extern,
false,
R->isFunctionProtoType());
New->setImplicit();
// Create Decl objects for each parameter, adding them to the
// FunctionDecl.
if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) {
SmallVector<ParmVarDecl*, 16> Params;
for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
ParmVarDecl *parm =
ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(),
nullptr, FT->getParamType(i), /*TInfo=*/nullptr,
SC_None, nullptr);
parm->setScopeInfo(0, i);
Params.push_back(parm);
}
New->setParams(Params);
}
AddKnownFunctionAttributes(New);
RegisterLocallyScopedExternCDecl(New, S);
// TUScope is the translation-unit scope to insert this function into.
// FIXME: This is hideous. We need to teach PushOnScopeChains to
// relate Scopes to DeclContexts, and probably eliminate CurContext
// entirely, but we're not there yet.
DeclContext *SavedContext = CurContext;
CurContext = Parent;
PushOnScopeChains(New, TUScope);
CurContext = SavedContext;
return New;
}
/// Typedef declarations don't have linkage, but they still denote the same
/// entity if their types are the same.
/// FIXME: This is notionally doing the same thing as ASTReaderDecl's
/// isSameEntity.
static void filterNonConflictingPreviousTypedefDecls(Sema &S,
TypedefNameDecl *Decl,
LookupResult &Previous) {
// This is only interesting when modules are enabled.
if (!S.getLangOpts().Modules && !S.getLangOpts().ModulesLocalVisibility)
return;
// Empty sets are uninteresting.
if (Previous.empty())
return;
LookupResult::Filter Filter = Previous.makeFilter();
while (Filter.hasNext()) {
NamedDecl *Old = Filter.next();
// Non-hidden declarations are never ignored.
if (S.isVisible(Old))
continue;
// Declarations of the same entity are not ignored, even if they have
// different linkages.
if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
if (S.Context.hasSameType(OldTD->getUnderlyingType(),
Decl->getUnderlyingType()))
continue;
// If both declarations give a tag declaration a typedef name for linkage
// purposes, then they declare the same entity.
if (S.getLangOpts().CPlusPlus &&
OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true) &&
Decl->getAnonDeclWithTypedefName())
continue;
}
Filter.erase();
}
Filter.done();
}
bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) {
QualType OldType;
if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old))
OldType = OldTypedef->getUnderlyingType();
else
OldType = Context.getTypeDeclType(Old);
QualType NewType = New->getUnderlyingType();
if (NewType->isVariablyModifiedType()) {
// Must not redefine a typedef with a variably-modified type.
int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef)
<< Kind << NewType;
if (Old->getLocation().isValid())
Diag(Old->getLocation(), diag::note_previous_definition);
New->setInvalidDecl();
return true;
}
if (OldType != NewType &&
!OldType->isDependentType() &&
!NewType->isDependentType() &&
!Context.hasSameType(OldType, NewType)) {
int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
Diag(New->getLocation(), diag::err_redefinition_different_typedef)
<< Kind << NewType << OldType;
if (Old->getLocation().isValid())
Diag(Old->getLocation(), diag::note_previous_definition);
New->setInvalidDecl();
return true;
}
return false;
}
/// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the
/// same name and scope as a previous declaration 'Old'. Figure out
/// how to resolve this situation, merging decls or emitting
/// diagnostics as appropriate. If there was an error, set New to be invalid.
///
void Sema::MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
LookupResult &OldDecls) {
// If the new decl is known invalid already, don't bother doing any
// merging checks.
if (New->isInvalidDecl()) return;
// Allow multiple definitions for ObjC built-in typedefs.
// FIXME: Verify the underlying types are equivalent!
if (getLangOpts().ObjC1) {
const IdentifierInfo *TypeID = New->getIdentifier();
switch (TypeID->getLength()) {
default: break;
case 2:
{
if (!TypeID->isStr("id"))
break;
QualType T = New->getUnderlyingType();
if (!T->isPointerType())
break;
if (!T->isVoidPointerType()) {
QualType PT = T->getAs<PointerType>()->getPointeeType();
if (!PT->isStructureType())
break;
}
Context.setObjCIdRedefinitionType(T);
// Install the built-in type for 'id', ignoring the current definition.
New->setTypeForDecl(Context.getObjCIdType().getTypePtr());
return;
}
case 5:
if (!TypeID->isStr("Class"))
break;
Context.setObjCClassRedefinitionType(New->getUnderlyingType());
// Install the built-in type for 'Class', ignoring the current definition.
New->setTypeForDecl(Context.getObjCClassType().getTypePtr());
return;
case 3:
if (!TypeID->isStr("SEL"))
break;
Context.setObjCSelRedefinitionType(New->getUnderlyingType());
// Install the built-in type for 'SEL', ignoring the current definition.
New->setTypeForDecl(Context.getObjCSelType().getTypePtr());
return;
}
// Fall through - the typedef name was not a builtin type.
}
// Verify the old decl was also a type.
TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>();
if (!Old) {
Diag(New->getLocation(), diag::err_redefinition_different_kind)
<< New->getDeclName();
NamedDecl *OldD = OldDecls.getRepresentativeDecl();
if (OldD->getLocation().isValid())
Diag(OldD->getLocation(), diag::note_previous_definition);
return New->setInvalidDecl();
}
// If the old declaration is invalid, just give up here.
if (Old->isInvalidDecl())
return New->setInvalidDecl();
if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
auto *OldTag = OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true);
auto *NewTag = New->getAnonDeclWithTypedefName();
NamedDecl *Hidden = nullptr;
if (getLangOpts().CPlusPlus && OldTag && NewTag &&
OldTag->getCanonicalDecl() != NewTag->getCanonicalDecl() &&
!hasVisibleDefinition(OldTag, &Hidden)) {
// There is a definition of this tag, but it is not visible. Use it
// instead of our tag.
New->setTypeForDecl(OldTD->getTypeForDecl());
if (OldTD->isModed())
New->setModedTypeSourceInfo(OldTD->getTypeSourceInfo(),
OldTD->getUnderlyingType());
else
New->setTypeSourceInfo(OldTD->getTypeSourceInfo());
// Make the old tag definition visible.
makeMergedDefinitionVisible(Hidden, NewTag->getLocation());
// If this was an unscoped enumeration, yank all of its enumerators
// out of the scope.
if (isa<EnumDecl>(NewTag)) {
Scope *EnumScope = getNonFieldDeclScope(S);
for (auto *D : NewTag->decls()) {
auto *ED = cast<EnumConstantDecl>(D);
assert(EnumScope->isDeclScope(ED));
EnumScope->RemoveDecl(ED);
IdResolver.RemoveDecl(ED);
ED->getLexicalDeclContext()->removeDecl(ED);
}
}
}
}
// If the typedef types are not identical, reject them in all languages and
// with any extensions enabled.
if (isIncompatibleTypedef(Old, New))
return;
// The types match. Link up the redeclaration chain and merge attributes if
// the old declaration was a typedef.
if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) {
New->setPreviousDecl(Typedef);
mergeDeclAttributes(New, Old);
}
if (getLangOpts().MicrosoftExt)
return;
if (getLangOpts().CPlusPlus) {
// C++ [dcl.typedef]p2:
// In a given non-class scope, a typedef specifier can be used to
// redefine the name of any type declared in that scope to refer
// to the type to which it already refers.
if (!isa<CXXRecordDecl>(CurContext))
return;
// C++0x [dcl.typedef]p4:
// In a given class scope, a typedef specifier can be used to redefine
// any class-name declared in that scope that is not also a typedef-name
// to refer to the type to which it already refers.
//
// This wording came in via DR424, which was a correction to the
// wording in DR56, which accidentally banned code like:
//
// struct S {
// typedef struct A { } A;
// };
//
// in the C++03 standard. We implement the C++0x semantics, which
// allow the above but disallow
//
// struct S {
// typedef int I;
// typedef int I;
// };
//
// since that was the intent of DR56.
if (!isa<TypedefNameDecl>(Old))
return;
Diag(New->getLocation(), diag::err_redefinition)
<< New->getDeclName();
Diag(Old->getLocation(), diag::note_previous_definition);
return New->setInvalidDecl();
}
// Modules always permit redefinition of typedefs, as does C11.
if (getLangOpts().Modules || getLangOpts().C11)
return;
// If we have a redefinition of a typedef in C, emit a warning. This warning
// is normally mapped to an error, but can be controlled with
// -Wtypedef-redefinition. If either the original or the redefinition is
// in a system header, don't emit this for compatibility with GCC.
if (getDiagnostics().getSuppressSystemWarnings() &&
(Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
Context.getSourceManager().isInSystemHeader(New->getLocation())))
return;
Diag(New->getLocation(), diag::ext_redefinition_of_typedef)
<< New->getDeclName();
Diag(Old->getLocation(), diag::note_previous_definition);
}
/// DeclhasAttr - returns true if decl Declaration already has the target
/// attribute.
static bool DeclHasAttr(const Decl *D, const Attr *A) {
const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A);
const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A);
for (const auto *i : D->attrs())
if (i->getKind() == A->getKind()) {
if (Ann) {
if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation())
return true;
continue;
}
// FIXME: Don't hardcode this check
if (OA && isa<OwnershipAttr>(i))
return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind();
return true;
}
return false;
}
static bool isAttributeTargetADefinition(Decl *D) {
if (VarDecl *VD = dyn_cast<VarDecl>(D))
return VD->isThisDeclarationADefinition();
if (TagDecl *TD = dyn_cast<TagDecl>(D))
return TD->isCompleteDefinition() || TD->isBeingDefined();
return true;
}
/// Merge alignment attributes from \p Old to \p New, taking into account the
/// special semantics of C11's _Alignas specifier and C++11's alignas attribute.
///
/// \return \c true if any attributes were added to \p New.
static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) {
// Look for alignas attributes on Old, and pick out whichever attribute
// specifies the strictest alignment requirement.
AlignedAttr *OldAlignasAttr = nullptr;
AlignedAttr *OldStrictestAlignAttr = nullptr;
unsigned OldAlign = 0;
for (auto *I : Old->specific_attrs<AlignedAttr>()) {
// FIXME: We have no way of representing inherited dependent alignments
// in a case like:
// template<int A, int B> struct alignas(A) X;
// template<int A, int B> struct alignas(B) X {};
// For now, we just ignore any alignas attributes which are not on the
// definition in such a case.
if (I->isAlignmentDependent())
return false;
if (I->isAlignas())
OldAlignasAttr = I;
unsigned Align = I->getAlignment(S.Context);
if (Align > OldAlign) {
OldAlign = Align;
OldStrictestAlignAttr = I;
}
}
// Look for alignas attributes on New.
AlignedAttr *NewAlignasAttr = nullptr;
unsigned NewAlign = 0;
for (auto *I : New->specific_attrs<AlignedAttr>()) {
if (I->isAlignmentDependent())
return false;
if (I->isAlignas())
NewAlignasAttr = I;
unsigned Align = I->getAlignment(S.Context);
if (Align > NewAlign)
NewAlign = Align;
}
if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) {
// Both declarations have 'alignas' attributes. We require them to match.
// C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but
// fall short. (If two declarations both have alignas, they must both match
// every definition, and so must match each other if there is a definition.)
// If either declaration only contains 'alignas(0)' specifiers, then it
// specifies the natural alignment for the type.
if (OldAlign == 0 || NewAlign == 0) {
QualType Ty;
if (ValueDecl *VD = dyn_cast<ValueDecl>(New))
Ty = VD->getType();
else
Ty = S.Context.getTagDeclType(cast<TagDecl>(New));
if (OldAlign == 0)
OldAlign = S.Context.getTypeAlign(Ty);
if (NewAlign == 0)
NewAlign = S.Context.getTypeAlign(Ty);
}
if (OldAlign != NewAlign) {
S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch)
<< (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity()
<< (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity();
S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration);
}
}
if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) {
// C++11 [dcl.align]p6:
// if any declaration of an entity has an alignment-specifier,
// every defining declaration of that entity shall specify an
// equivalent alignment.
// C11 6.7.5/7:
// If the definition of an object does not have an alignment
// specifier, any other declaration of that object shall also
// have no alignment specifier.
S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition)
<< OldAlignasAttr;
S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration)
<< OldAlignasAttr;
}
bool AnyAdded = false;
// Ensure we have an attribute representing the strictest alignment.
if (OldAlign > NewAlign) {
AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context);
Clone->setInherited(true);
New->addAttr(Clone);
AnyAdded = true;
}
// Ensure we have an alignas attribute if the old declaration had one.
if (OldAlignasAttr && !NewAlignasAttr &&
!(AnyAdded && OldStrictestAlignAttr->isAlignas())) {
AlignedAttr *Clone = OldAlignasAttr->clone(S.Context);
Clone->setInherited(true);
New->addAttr(Clone);
AnyAdded = true;
}
return AnyAdded;
}
static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
const InheritableAttr *Attr,
Sema::AvailabilityMergeKind AMK) {
InheritableAttr *NewAttr = nullptr;
unsigned AttrSpellingListIndex = Attr->getSpellingListIndex();
if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr))
NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(),
AA->getIntroduced(), AA->getDeprecated(),
AA->getObsoleted(), AA->getUnavailable(),
AA->getMessage(), AMK,
AttrSpellingListIndex);
else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
AttrSpellingListIndex);
else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
AttrSpellingListIndex);
else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(),
AttrSpellingListIndex);
else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr))
NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(),
AttrSpellingListIndex);
else if (const auto *FA = dyn_cast<FormatAttr>(Attr))
NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(),
FA->getFormatIdx(), FA->getFirstArg(),
AttrSpellingListIndex);
else if (const auto *SA = dyn_cast<SectionAttr>(Attr))
NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(),
AttrSpellingListIndex);
else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr))
NewAttr = S.mergeMSInheritanceAttr(D, IA->getRange(), IA->getBestCase(),
AttrSpellingListIndex,
IA->getSemanticSpelling());
else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr))
NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
&S.Context.Idents.get(AA->getSpelling()),
AttrSpellingListIndex);
else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
else if (const auto *InternalLinkageA = dyn_cast<InternalLinkageAttr>(Attr))
NewAttr = S.mergeInternalLinkageAttr(
D, InternalLinkageA->getRange(),
&S.Context.Idents.get(InternalLinkageA->getSpelling()),
AttrSpellingListIndex);
else if (const auto *CommonA = dyn_cast<CommonAttr>(Attr))
NewAttr = S.mergeCommonAttr(D, CommonA->getRange(),
&S.Context.Idents.get(CommonA->getSpelling()),
AttrSpellingListIndex);
else if (isa<AlignedAttr>(Attr))
// AlignedAttrs are handled separately, because we need to handle all
// such attributes on a declaration at the same time.
NewAttr = nullptr;
else if ((isa<DeprecatedAttr>(Attr) || isa<UnavailableAttr>(Attr)) &&
(AMK == Sema::AMK_Override ||
AMK == Sema::AMK_ProtocolImplementation))
NewAttr = nullptr;
else if (Attr->duplicatesAllowed() || !DeclHasAttr(D, Attr))
NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
if (NewAttr) {
NewAttr->setInherited(true);
D->addAttr(NewAttr);
return true;
}
return false;
}
static const Decl *getDefinition(const Decl *D) {
if (const TagDecl *TD = dyn_cast<TagDecl>(D))
return TD->getDefinition();
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
const VarDecl *Def = VD->getDefinition();
if (Def)
return Def;
return VD->getActingDefinition();
}
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
const FunctionDecl* Def;
if (FD->isDefined(Def))
return Def;
}
return nullptr;
}
static bool hasAttribute(const Decl *D, attr::Kind Kind) {
for (const auto *Attribute : D->attrs())
if (Attribute->getKind() == Kind)
return true;
return false;
}
/// checkNewAttributesAfterDef - If we already have a definition, check that
/// there are no new attributes in this declaration.
static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) {
if (!New->hasAttrs())
return;
const Decl *Def = getDefinition(Old);
if (!Def || Def == New)
return;
AttrVec &NewAttributes = New->getAttrs();
for (unsigned I = 0, E = NewAttributes.size(); I != E;) {
const Attr *NewAttribute = NewAttributes[I];
if (isa<AliasAttr>(NewAttribute)) {
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) {
Sema::SkipBodyInfo SkipBody;
S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def), &SkipBody);
// If we're skipping this definition, drop the "alias" attribute.
if (SkipBody.ShouldSkip) {
NewAttributes.erase(NewAttributes.begin() + I);
--E;
continue;
}
} else {
VarDecl *VD = cast<VarDecl>(New);
unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() ==
VarDecl::TentativeDefinition
? diag::err_alias_after_tentative
: diag::err_redefinition;
S.Diag(VD->getLocation(), Diag) << VD->getDeclName();
S.Diag(Def->getLocation(), diag::note_previous_definition);
VD->setInvalidDecl();
}
++I;
continue;
}
if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) {
// Tentative definitions are only interesting for the alias check above.
if (VD->isThisDeclarationADefinition() != VarDecl::Definition) {
++I;
continue;
}
}
if (hasAttribute(Def, NewAttribute->getKind())) {
++I;
continue; // regular attr merging will take care of validating this.
}
if (isa<C11NoReturnAttr>(NewAttribute)) {
// C's _Noreturn is allowed to be added to a function after it is defined.
++I;
continue;
} else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) {
if (AA->isAlignas()) {
// C++11 [dcl.align]p6:
// if any declaration of an entity has an alignment-specifier,
// every defining declaration of that entity shall specify an
// equivalent alignment.
// C11 6.7.5/7:
// If the definition of an object does not have an alignment
// specifier, any other declaration of that object shall also
// have no alignment specifier.
S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition)
<< AA;
S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration)
<< AA;
NewAttributes.erase(NewAttributes.begin() + I);
--E;
continue;
}
}
S.Diag(NewAttribute->getLocation(),
diag::warn_attribute_precede_definition);
S.Diag(Def->getLocation(), diag::note_previous_definition);
NewAttributes.erase(NewAttributes.begin() + I);
--E;
}
}
/// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
AvailabilityMergeKind AMK) {
if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) {
UsedAttr *NewAttr = OldAttr->clone(Context);
NewAttr->setInherited(true);
New->addAttr(NewAttr);
}
if (!Old->hasAttrs() && !New->hasAttrs())
return;
// Attributes declared post-definition are currently ignored.
checkNewAttributesAfterDef(*this, New, Old);
if (AsmLabelAttr *NewA = New->getAttr<AsmLabelAttr>()) {
if (AsmLabelAttr *OldA = Old->getAttr<AsmLabelAttr>()) {
if (OldA->getLabel() != NewA->getLabel()) {
// This redeclaration changes __asm__ label.
Diag(New->getLocation(), diag::err_different_asm_label);
Diag(OldA->getLocation(), diag::note_previous_declaration);
}
} else if (Old->isUsed()) {
// This redeclaration adds an __asm__ label to a declaration that has
// already been ODR-used.
Diag(New->getLocation(), diag::err_late_asm_label_name)
<< isa<FunctionDecl>(Old) << New->getAttr<AsmLabelAttr>()->getRange();
}
}
if (!Old->hasAttrs())
return;
bool foundAny = New->hasAttrs();
// Ensure that any moving of objects within the allocated map is done before
// we process them.
if (!foundAny) New->setAttrs(AttrVec());
for (auto *I : Old->specific_attrs<InheritableAttr>()) {
// Ignore deprecated/unavailable/availability attributes if requested.
AvailabilityMergeKind LocalAMK = AMK_None;
if (isa<DeprecatedAttr>(I) ||
isa<UnavailableAttr>(I) ||
isa<AvailabilityAttr>(I)) {
switch (AMK) {
case AMK_None:
continue;
case AMK_Redeclaration:
case AMK_Override:
case AMK_ProtocolImplementation:
LocalAMK = AMK;
break;
}
}
// Already handled.
if (isa<UsedAttr>(I))
continue;
if (mergeDeclAttribute(*this, New, I, LocalAMK))
foundAny = true;
}
if (mergeAlignedAttrs(*this, New, Old))
foundAny = true;
if (!foundAny) New->dropAttrs();
}
/// mergeParamDeclAttributes - Copy attributes from the old parameter
/// to the new one.
static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
const ParmVarDecl *oldDecl,
Sema &S) {
// C++11 [dcl.attr.depend]p2:
// The first declaration of a function shall specify the
// carries_dependency attribute for its declarator-id if any declaration
// of the function specifies the carries_dependency attribute.
const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>();
if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) {
S.Diag(CDA->getLocation(),
diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/;
// Find the first declaration of the parameter.
// FIXME: Should we build redeclaration chains for function parameters?
const FunctionDecl *FirstFD =
cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl();
const ParmVarDecl *FirstVD =
FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex());
S.Diag(FirstVD->getLocation(),
diag::note_carries_dependency_missing_first_decl) << 1/*Param*/;
}
if (!oldDecl->hasAttrs())
return;
bool foundAny = newDecl->hasAttrs();
// Ensure that any moving of objects within the allocated map is
// done before we process them.
if (!foundAny) newDecl->setAttrs(AttrVec());
for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) {
if (!DeclHasAttr(newDecl, I)) {
InheritableAttr *newAttr =
cast<InheritableParamAttr>(I->clone(S.Context));
newAttr->setInherited(true);
newDecl->addAttr(newAttr);
foundAny = true;
}
}
if (!foundAny) newDecl->dropAttrs();
}
static void mergeParamDeclTypes(ParmVarDecl *NewParam,
const ParmVarDecl *OldParam,
Sema &S) {
if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) {
if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) {
if (*Oldnullability != *Newnullability) {
S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr)
<< DiagNullabilityKind(
*Newnullability,
((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
!= 0))
<< DiagNullabilityKind(
*Oldnullability,
((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
!= 0));
S.Diag(OldParam->getLocation(), diag::note_previous_declaration);
}
} else {
QualType NewT = NewParam->getType();
NewT = S.Context.getAttributedType(
AttributedType::getNullabilityAttrKind(*Oldnullability),
NewT, NewT);
NewParam->setType(NewT);
}
}
}
namespace {
/// Used in MergeFunctionDecl to keep track of function parameters in
/// C.
struct GNUCompatibleParamWarning {
ParmVarDecl *OldParm;
ParmVarDecl *NewParm;
QualType PromotedType;
};
}
/// getSpecialMember - get the special member enum for a method.
Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) {
if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
if (Ctor->isDefaultConstructor())
return Sema::CXXDefaultConstructor;
if (Ctor->isCopyConstructor())
return Sema::CXXCopyConstructor;
if (Ctor->isMoveConstructor())
return Sema::CXXMoveConstructor;
} else if (isa<CXXDestructorDecl>(MD)) {
return Sema::CXXDestructor;
} else if (MD->isCopyAssignmentOperator()) {
return Sema::CXXCopyAssignment;
} else if (MD->isMoveAssignmentOperator()) {
return Sema::CXXMoveAssignment;
}
return Sema::CXXInvalid;
}
// Determine whether the previous declaration was a definition, implicit
// declaration, or a declaration.
template <typename T>
static std::pair<diag::kind, SourceLocation>
getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) {
diag::kind PrevDiag;
SourceLocation OldLocation = Old->getLocation();
if (Old->isThisDeclarationADefinition())
PrevDiag = diag::note_previous_definition;
else if (Old->isImplicit()) {
PrevDiag = diag::note_previous_implicit_declaration;
if (OldLocation.isInvalid())
OldLocation = New->getLocation();
} else
PrevDiag = diag::note_previous_declaration;
return std::make_pair(PrevDiag, OldLocation);
}
/// canRedefineFunction - checks if a function can be redefined. Currently,
/// only extern inline functions can be redefined, and even then only in
/// GNU89 mode.
static bool canRedefineFunction(const FunctionDecl *FD,
const LangOptions& LangOpts) {
return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) &&
!LangOpts.CPlusPlus &&
FD->isInlineSpecified() &&
FD->getStorageClass() == SC_Extern);
}
const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
const AttributedType *AT = T->getAs<AttributedType>();
while (AT && !AT->isCallingConv())
AT = AT->getModifiedType()->getAs<AttributedType>();
return AT;
}
template <typename T>
static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) {
const DeclContext *DC = Old->getDeclContext();
if (DC->isRecord())
return false;
LanguageLinkage OldLinkage = Old->getLanguageLinkage();
if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext())
return true;
if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext())
return true;
return false;
}
template<typename T> static bool isExternC(T *D) { return D->isExternC(); }
static bool isExternC(VarTemplateDecl *) { return false; }
/// \brief Check whether a redeclaration of an entity introduced by a
/// using-declaration is valid, given that we know it's not an overload
/// (nor a hidden tag declaration).
template<typename ExpectedDecl>
static bool checkUsingShadowRedecl(Sema &S, UsingShadowDecl *OldS,
ExpectedDecl *New) {
// C++11 [basic.scope.declarative]p4:
// Given a set of declarations in a single declarative region, each of
// which specifies the same unqualified name,
// -- they shall all refer to the same entity, or all refer to functions
// and function templates; or
// -- exactly one declaration shall declare a class name or enumeration
// name that is not a typedef name and the other declarations shall all
// refer to the same variable or enumerator, or all refer to functions
// and function templates; in this case the class name or enumeration
// name is hidden (3.3.10).
// C++11 [namespace.udecl]p14:
// If a function declaration in namespace scope or block scope has the
// same name and the same parameter-type-list as a function introduced
// by a using-declaration, and the declarations do not declare the same
// function, the program is ill-formed.
auto *Old = dyn_cast<ExpectedDecl>(OldS->getTargetDecl());
if (Old &&
!Old->getDeclContext()->getRedeclContext()->Equals(
New->getDeclContext()->getRedeclContext()) &&
!(isExternC(Old) && isExternC(New)))
Old = nullptr;
if (!Old) {
S.Diag(New->getLocation(), diag::err_using_decl_conflict_reverse);
S.Diag(OldS->getTargetDecl()->getLocation(), diag::note_using_decl_target);
S.Diag(OldS->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
return true;
}
return false;
}
static bool hasIdenticalPassObjectSizeAttrs(const FunctionDecl *A,
const FunctionDecl *B) {
assert(A->getNumParams() == B->getNumParams());
auto AttrEq = [](const ParmVarDecl *A, const ParmVarDecl *B) {
const auto *AttrA = A->getAttr<PassObjectSizeAttr>();
const auto *AttrB = B->getAttr<PassObjectSizeAttr>();
if (AttrA == AttrB)
return true;
return AttrA && AttrB && AttrA->getType() == AttrB->getType();
};
return std::equal(A->param_begin(), A->param_end(), B->param_begin(), AttrEq);
}
/// MergeFunctionDecl - We just parsed a function 'New' from
/// declarator D which has the same name and scope as a previous
/// declaration 'Old'. Figure out how to resolve this situation,
/// merging decls or emitting diagnostics as appropriate.
///
/// In C++, New and Old must be declarations that are not
/// overloaded. Use IsOverload to determine whether New and Old are
/// overloaded, and to select the Old declaration that New should be
/// merged with.
///
/// Returns true if there was an error, false otherwise.
bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
Scope *S, bool MergeTypeWithOld) {
// Verify the old decl was also a function.
FunctionDecl *Old = OldD->getAsFunction();
if (!Old) {
if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) {
if (New->getFriendObjectKind()) {
Diag(New->getLocation(), diag::err_using_decl_friend);
Diag(Shadow->getTargetDecl()->getLocation(),
diag::note_using_decl_target);
Diag(Shadow->getUsingDecl()->getLocation(),
diag::note_using_decl) << 0;
return true;
}
// Check whether the two declarations might declare the same function.
if (checkUsingShadowRedecl<FunctionDecl>(*this, Shadow, New))
return true;
OldD = Old = cast<FunctionDecl>(Shadow->getTargetDecl());
} else {
Diag(New->getLocation(), diag::err_redefinition_different_kind)
<< New->getDeclName();
Diag(OldD->getLocation(), diag::note_previous_definition);
return true;
}
}
// If the old declaration is invalid, just give up here.
if (Old->isInvalidDecl())
return true;
diag::kind PrevDiag;
SourceLocation OldLocation;
std::tie(PrevDiag, OldLocation) =
getNoteDiagForInvalidRedeclaration(Old, New);
// Don't complain about this if we're in GNU89 mode and the old function
// is an extern inline function.
// Don't complain about specializations. They are not supposed to have
// storage classes.
if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) &&
New->getStorageClass() == SC_Static &&
Old->hasExternalFormalLinkage() &&
!New->getTemplateSpecializationInfo() &&
!canRedefineFunction(Old, getLangOpts())) {
if (getLangOpts().MicrosoftExt) {
Diag(New->getLocation(), diag::ext_static_non_static) << New;
Diag(OldLocation, PrevDiag);
} else {
Diag(New->getLocation(), diag::err_static_non_static) << New;
Diag(OldLocation, PrevDiag);
return true;
}
}
if (New->hasAttr<InternalLinkageAttr>() &&
!Old->hasAttr<InternalLinkageAttr>()) {
Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
<< New->getDeclName();
Diag(Old->getLocation(), diag::note_previous_definition);
New->dropAttr<InternalLinkageAttr>();
}
// If a function is first declared with a calling convention, but is later
// declared or defined without one, all following decls assume the calling
// convention of the first.
//
// It's OK if a function is first declared without a calling convention,
// but is later declared or defined with the default calling convention.
//
// To test if either decl has an explicit calling convention, we look for
// AttributedType sugar nodes on the type as written. If they are missing or
// were canonicalized away, we assume the calling convention was implicit.
//
// Note also that we DO NOT return at this point, because we still have
// other tests to run.
QualType OldQType = Context.getCanonicalType(Old->getType());
QualType NewQType = Context.getCanonicalType(New->getType());
const FunctionType *OldType = cast<FunctionType>(OldQType);
const FunctionType *NewType = cast<FunctionType>(NewQType);
FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
bool RequiresAdjustment = false;
if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
FunctionDecl *First = Old->getFirstDecl();
const FunctionType *FT =
First->getType().getCanonicalType()->castAs<FunctionType>();
FunctionType::ExtInfo FI = FT->getExtInfo();
bool NewCCExplicit = getCallingConvAttributedType(New->getType());
if (!NewCCExplicit) {
// Inherit the CC from the previous declaration if it was specified
// there but not here.
NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
RequiresAdjustment = true;
} else {
// Calling conventions aren't compatible, so complain.
bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
Diag(New->getLocation(), diag::err_cconv_change)
<< FunctionType::getNameForCallConv(NewTypeInfo.getCC())
<< !FirstCCExplicit
<< (!FirstCCExplicit ? "" :
FunctionType::getNameForCallConv(FI.getCC()));
// Put the note on the first decl, since it is the one that matters.
Diag(First->getLocation(), diag::note_previous_declaration);
return true;
}
}
// FIXME: diagnose the other way around?
if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) {
NewTypeInfo = NewTypeInfo.withNoReturn(true);
RequiresAdjustment = true;
}
// Merge regparm attribute.
if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() ||
OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) {
if (NewTypeInfo.getHasRegParm()) {
Diag(New->getLocation(), diag::err_regparm_mismatch)
<< NewType->getRegParmType()
<< OldType->getRegParmType();
Diag(OldLocation, diag::note_previous_declaration);
return true;
}
NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm());
RequiresAdjustment = true;
}
// Merge ns_returns_retained attribute.
if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
if (NewTypeInfo.getProducesResult()) {
Diag(New->getLocation(), diag::err_returns_retained_mismatch);
Diag(OldLocation, diag::note_previous_declaration);
return true;
}
NewTypeInfo = NewTypeInfo.withProducesResult(true);
RequiresAdjustment = true;
}
if (RequiresAdjustment) {
const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
New->setType(QualType(AdjustedType, 0));
NewQType = Context.getCanonicalType(New->getType());
NewType = cast<FunctionType>(NewQType);
}
// If this redeclaration makes the function inline, we may need to add it to
// UndefinedButUsed.
if (!Old->isInlined() && New->isInlined() &&
!New->hasAttr<GNUInlineAttr>() &&
!getLangOpts().GNUInline &&
Old->isUsed(false) &&
!Old->isDefined() && !New->isThisDeclarationADefinition())
UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
SourceLocation()));
// If this redeclaration makes it newly gnu_inline, we don't want to warn
// about it.
if (New->hasAttr<GNUInlineAttr>() &&
Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
UndefinedButUsed.erase(Old->getCanonicalDecl());
}
// If pass_object_size params don't match up perfectly, this isn't a valid
// redeclaration.
if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() &&
!hasIdenticalPassObjectSizeAttrs(Old, New)) {
Diag(New->getLocation(), diag::err_different_pass_object_size_params)
<< New->getDeclName();
Diag(OldLocation, PrevDiag) << Old << Old->getType();
return true;
}
if (getLangOpts().CPlusPlus) {
// (C++98 13.1p2):
// Certain function declarations cannot be overloaded:
// -- Function declarations that differ only in the return type
// cannot be overloaded.
// Go back to the type source info to compare the declared return types,
// per C++1y [dcl.type.auto]p13:
// Redeclarations or specializations of a function or function template
// with a declared return type that uses a placeholder type shall also
// use that placeholder, not a deduced type.
QualType OldDeclaredReturnType =
(Old->getTypeSourceInfo()
? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>()
: OldType)->getReturnType();
QualType NewDeclaredReturnType =
(New->getTypeSourceInfo()
? New->getTypeSourceInfo()->getType()->castAs<FunctionType>()
: NewType)->getReturnType();
QualType ResQT;
if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
!((NewQType->isDependentType() || OldQType->isDependentType()) &&
New->isLocalExternDecl())) {
if (NewDeclaredReturnType->isObjCObjectPointerType() &&
OldDeclaredReturnType->isObjCObjectPointerType())
ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
if (ResQT.isNull()) {
if (New->isCXXClassMember() && New->isOutOfLine())
Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
<< New << New->getReturnTypeSourceRange();
else
Diag(New->getLocation(), diag::err_ovl_diff_return_type)
<< New->getReturnTypeSourceRange();
Diag(OldLocation, PrevDiag) << Old << Old->getType()
<< Old->getReturnTypeSourceRange();
return true;
}
else
NewQType = ResQT;
}
QualType OldReturnType = OldType->getReturnType();
QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
if (OldReturnType != NewReturnType) {
// If this function has a deduced return type and has already been
// defined, copy the deduced value from the old declaration.
AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
if (OldAT && OldAT->isDeduced()) {
New->setType(
SubstAutoType(New->getType(),
OldAT->isDependentType() ? Context.DependentTy
: OldAT->getDeducedType()));
NewQType = Context.getCanonicalType(
SubstAutoType(NewQType,
OldAT->isDependentType() ? Context.DependentTy
: OldAT->getDeducedType()));
}
}
const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
if (OldMethod && NewMethod) {
// Preserve triviality.
NewMethod->setTrivial(OldMethod->isTrivial());
// MSVC allows explicit template specialization at class scope:
// 2 CXXMethodDecls referring to the same function will be injected.
// We don't want a redeclaration error.
bool IsClassScopeExplicitSpecialization =
OldMethod->isFunctionTemplateSpecialization() &&
NewMethod->isFunctionTemplateSpecialization();
bool isFriend = NewMethod->getFriendObjectKind();
if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
!IsClassScopeExplicitSpecialization) {
// -- Member function declarations with the same name and the
// same parameter types cannot be overloaded if any of them
// is a static member function declaration.
if (OldMethod->isStatic() != NewMethod->isStatic()) {
Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
Diag(OldLocation, PrevDiag) << Old << Old->getType();
return true;
}
// C++ [class.mem]p1:
// [...] A member shall not be declared twice in the
// member-specification, except that a nested class or member
// class template can be declared and then later defined.
if (ActiveTemplateInstantiations.empty()) {
unsigned NewDiag;
if (isa<CXXConstructorDecl>(OldMethod))
NewDiag = diag::err_constructor_redeclared;
else if (isa<CXXDestructorDecl>(NewMethod))
NewDiag = diag::err_destructor_redeclared;
else if (isa<CXXConversionDecl>(NewMethod))
NewDiag = diag::err_conv_function_redeclared;
else
NewDiag = diag::err_member_redeclared;
Diag(New->getLocation(), NewDiag);
} else {
Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
<< New << New->getType();
}
Diag(OldLocation, PrevDiag) << Old << Old->getType();
return true;
// Complain if this is an explicit declaration of a special
// member that was initially declared implicitly.
//
// As an exception, it's okay to befriend such methods in order
// to permit the implicit constructor/destructor/operator calls.
} else if (OldMethod->isImplicit()) {
if (isFriend) {
NewMethod->setImplicit();
} else {
Diag(NewMethod->getLocation(),
diag::err_definition_of_implicitly_declared_member)
<< New << getSpecialMember(OldMethod);
return true;
}
} else if (OldMethod->isExplicitlyDefaulted() && !isFriend) {
Diag(NewMethod->getLocation(),
diag::err_definition_of_explicitly_defaulted_member)
<< getSpecialMember(OldMethod);
return true;
}
}
// C++11 [dcl.attr.noreturn]p1:
// The first declaration of a function shall specify the noreturn
// attribute if any declaration of that function specifies the noreturn
// attribute.
const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
Diag(Old->getFirstDecl()->getLocation(),
diag::note_noreturn_missing_first_decl);
}
// C++11 [dcl.attr.depend]p2:
// The first declaration of a function shall specify the
// carries_dependency attribute for its declarator-id if any declaration
// of the function specifies the carries_dependency attribute.
const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
Diag(CDA->getLocation(),
diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
Diag(Old->getFirstDecl()->getLocation(),
diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
}
// (C++98 8.3.5p3):
// All declarations for a function shall agree exactly in both the
// return type and the parameter-type-list.
// We also want to respect all the extended bits except noreturn.
// noreturn should now match unless the old type info didn't have it.
QualType OldQTypeForComparison = OldQType;
if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
assert(OldQType == QualType(OldType, 0));
const FunctionType *OldTypeForComparison
= Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
OldQTypeForComparison = QualType(OldTypeForComparison, 0);
assert(OldQTypeForComparison.isCanonical());
}
if (haveIncompatibleLanguageLinkages(Old, New)) {
// As a special case, retain the language linkage from previous
// declarations of a friend function as an extension.
//
// This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
// and is useful because there's otherwise no way to specify language
// linkage within class scope.
//
// Check cautiously as the friend object kind isn't yet complete.
if (New->getFriendObjectKind() != Decl::FOK_None) {
Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
Diag(OldLocation, PrevDiag);
} else {
Diag(New->getLocation(), diag::err_different_language_linkage) << New;
Diag(OldLocation, PrevDiag);
return true;
}
}
if (OldQTypeForComparison == NewQType)
return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
if ((NewQType->isDependentType() || OldQType->isDependentType()) &&
New->isLocalExternDecl()) {
// It's OK if we couldn't merge types for a local function declaraton
// if either the old or new type is dependent. We'll merge the types
// when we instantiate the function.
return false;
}
// Fall through for conflicting redeclarations and redefinitions.
}
// C: Function types need to be compatible, not identical. This handles
// duplicate function decls like "void f(int); void f(enum X);" properly.
if (!getLangOpts().CPlusPlus &&
Context.typesAreCompatible(OldQType, NewQType)) {
const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
const FunctionProtoType *OldProto = nullptr;
if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
(OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
// The old declaration provided a function prototype, but the
// new declaration does not. Merge in the prototype.
assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
NewQType =
Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
OldProto->getExtProtoInfo());
New->setType(NewQType);
New->setHasInheritedPrototype();
// Synthesize parameters with the same types.
SmallVector<ParmVarDecl*, 16> Params;
for (const auto &ParamType : OldProto->param_types()) {
ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
SourceLocation(), nullptr,
ParamType, /*TInfo=*/nullptr,
SC_None, nullptr);
Param->setScopeInfo(0, Params.size());
Param->setImplicit();
Params.push_back(Param);
}
New->setParams(Params);
}
return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
}
// GNU C permits a K&R definition to follow a prototype declaration
// if the declared types of the parameters in the K&R definition
// match the types in the prototype declaration, even when the
// promoted types of the parameters from the K&R definition differ
// from the types in the prototype. GCC then keeps the types from
// the prototype.
//
// If a variadic prototype is followed by a non-variadic K&R definition,
// the K&R definition becomes variadic. This is sort of an edge case, but
// it's legal per the standard depending on how you read C99 6.7.5.3p15 and
// C99 6.9.1p8.
if (!getLangOpts().CPlusPlus &&
Old->hasPrototype() && !New->hasPrototype() &&
New->getType()->getAs<FunctionProtoType>() &&
Old->getNumParams() == New->getNumParams()) {
SmallVector<QualType, 16> ArgTypes;
SmallVector<GNUCompatibleParamWarning, 16> Warnings;
const FunctionProtoType *OldProto
= Old->getType()->getAs<FunctionProtoType>();
const FunctionProtoType *NewProto
= New->getType()->getAs<FunctionProtoType>();
// Determine whether this is the GNU C extension.
QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
NewProto->getReturnType());
bool LooseCompatible = !MergedReturn.isNull();
for (unsigned Idx = 0, End = Old->getNumParams();
LooseCompatible && Idx != End; ++Idx) {
ParmVarDecl *OldParm = Old->getParamDecl(Idx);
ParmVarDecl *NewParm = New->getParamDecl(Idx);
if (Context.typesAreCompatible(OldParm->getType(),
NewProto->getParamType(Idx))) {
ArgTypes.push_back(NewParm->getType());
} else if (Context.typesAreCompatible(OldParm->getType(),
NewParm->getType(),
/*CompareUnqualified=*/true)) {
GNUCompatibleParamWarning Warn = { OldParm, NewParm,
NewProto->getParamType(Idx) };
Warnings.push_back(Warn);
ArgTypes.push_back(NewParm->getType());
} else
LooseCompatible = false;
}
if (LooseCompatible) {
for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
Diag(Warnings[Warn].NewParm->getLocation(),
diag::ext_param_promoted_not_compatible_with_prototype)
<< Warnings[Warn].PromotedType
<< Warnings[Warn].OldParm->getType();
if (Warnings[Warn].OldParm->getLocation().isValid())
Diag(Warnings[Warn].OldParm->getLocation(),
diag::note_previous_declaration);
}
if (MergeTypeWithOld)
New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
OldProto->getExtProtoInfo()));
return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
}
// Fall through to diagnose conflicting types.
}
// A function that has already been declared has been redeclared or
// defined with a different type; show an appropriate diagnostic.
// If the previous declaration was an implicitly-generated builtin
// declaration, then at the very least we should use a specialized note.
unsigned BuiltinID;
if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
// If it's actually a library-defined builtin function like 'malloc'
// or 'printf', just warn about the incompatible redeclaration.
if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
Diag(OldLocation, diag::note_previous_builtin_declaration)
<< Old << Old->getType();
// If this is a global redeclaration, just forget hereafter
// about the "builtin-ness" of the function.
//
// Doing this for local extern declarations is problematic. If
// the builtin declaration remains visible, a second invalid
// local declaration will produce a hard error; if it doesn't
// remain visible, a single bogus local redeclaration (which is
// actually only a warning) could break all the downstream code.
if (!New->getLexicalDeclContext()->isFunctionOrMethod())
New->getIdentifier()->revertBuiltin();
return false;
}
PrevDiag = diag::note_previous_builtin_declaration;
}
Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
Diag(OldLocation, PrevDiag) << Old << Old->getType();
return true;
}
/// \brief Completes the merge of two function declarations that are
/// known to be compatible.
///
/// This routine handles the merging of attributes and other
/// properties of function declarations from the old declaration to
/// the new declaration, once we know that New is in fact a
/// redeclaration of Old.
///
/// \returns false
bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
Scope *S, bool MergeTypeWithOld) {
// Merge the attributes
mergeDeclAttributes(New, Old);
// Merge "pure" flag.
if (Old->isPure())
New->setPure();
// Merge "used" flag.
if (Old->getMostRecentDecl()->isUsed(false))
New->setIsUsed();
// Merge attributes from the parameters. These can mismatch with K&R
// declarations.
if (New->getNumParams() == Old->getNumParams())
for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) {
ParmVarDecl *NewParam = New->getParamDecl(i);
ParmVarDecl *OldParam = Old->getParamDecl(i);
mergeParamDeclAttributes(NewParam, OldParam, *this);
mergeParamDeclTypes(NewParam, OldParam, *this);
}
if (getLangOpts().CPlusPlus)
return MergeCXXFunctionDecl(New, Old, S);
// Merge the function types so the we get the composite types for the return
// and argument types. Per C11 6.2.7/4, only update the type if the old decl
// was visible.
QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
if (!Merged.isNull() && MergeTypeWithOld)
New->setType(Merged);
return false;
}
void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
ObjCMethodDecl *oldMethod) {
// Merge the attributes, including deprecated/unavailable
AvailabilityMergeKind MergeKind =
isa<ObjCProtocolDecl>(oldMethod->getDeclContext())
? AMK_ProtocolImplementation
: isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
: AMK_Override;
mergeDeclAttributes(newMethod, oldMethod, MergeKind);
// Merge attributes from the parameters.
ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
oe = oldMethod->param_end();
for (ObjCMethodDecl::param_iterator
ni = newMethod->param_begin(), ne = newMethod->param_end();
ni != ne && oi != oe; ++ni, ++oi)
mergeParamDeclAttributes(*ni, *oi, *this);
CheckObjCMethodOverride(newMethod, oldMethod);
}
/// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
/// scope as a previous declaration 'Old'. Figure out how to merge their types,
/// emitting diagnostics as appropriate.
///
/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
/// to here in AddInitializerToDecl. We can't check them before the initializer
/// is attached.
void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
bool MergeTypeWithOld) {
if (New->isInvalidDecl() || Old->isInvalidDecl())
return;
QualType MergedT;
if (getLangOpts().CPlusPlus) {
if (New->getType()->isUndeducedType()) {
// We don't know what the new type is until the initializer is attached.
return;
} else if (Context.hasSameType(New->getType(), Old->getType())) {
// These could still be something that needs exception specs checked.
return MergeVarDeclExceptionSpecs(New, Old);
}
// C++ [basic.link]p10:
// [...] the types specified by all declarations referring to a given
// object or function shall be identical, except that declarations for an
// array object can specify array types that differ by the presence or
// absence of a major array bound (8.3.4).
else if (Old->getType()->isIncompleteArrayType() &&
New->getType()->isArrayType()) {
const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
const ArrayType *NewArray = Context.getAsArrayType(New->getType());
if (Context.hasSameType(OldArray->getElementType(),
NewArray->getElementType()))
MergedT = New->getType();
} else if (Old->getType()->isArrayType() &&
New->getType()->isIncompleteArrayType()) {
const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
const ArrayType *NewArray = Context.getAsArrayType(New->getType());
if (Context.hasSameType(OldArray->getElementType(),
NewArray->getElementType()))
MergedT = Old->getType();
} else if (New->getType()->isObjCObjectPointerType() &&
Old->getType()->isObjCObjectPointerType()) {
MergedT = Context.mergeObjCGCQualifiers(New->getType(),
Old->getType());
}
} else {
// C 6.2.7p2:
// All declarations that refer to the same object or function shall have
// compatible type.
MergedT = Context.mergeTypes(New->getType(), Old->getType());
}
if (MergedT.isNull()) {
// It's OK if we couldn't merge types if either type is dependent, for a
// block-scope variable. In other cases (static data members of class
// templates, variable templates, ...), we require the types to be
// equivalent.
// FIXME: The C++ standard doesn't say anything about this.
if ((New->getType()->isDependentType() ||
Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
// If the old type was dependent, we can't merge with it, so the new type
// becomes dependent for now. We'll reproduce the original type when we
// instantiate the TypeSourceInfo for the variable.
if (!New->getType()->isDependentType() && MergeTypeWithOld)
New->setType(Context.DependentTy);
return;
}
// FIXME: Even if this merging succeeds, some other non-visible declaration
// of this variable might have an incompatible type. For instance:
//
// extern int arr[];
// void f() { extern int arr[2]; }
// void g() { extern int arr[3]; }
//
// Neither C nor C++ requires a diagnostic for this, but we should still try
// to diagnose it.
Diag(New->getLocation(), New->isThisDeclarationADefinition()
? diag::err_redefinition_different_type
: diag::err_redeclaration_different_type)
<< New->getDeclName() << New->getType() << Old->getType();
diag::kind PrevDiag;
SourceLocation OldLocation;
std::tie(PrevDiag, OldLocation) =
getNoteDiagForInvalidRedeclaration(Old, New);
Diag(OldLocation, PrevDiag);
return New->setInvalidDecl();
}
// Don't actually update the type on the new declaration if the old
// declaration was an extern declaration in a different scope.
if (MergeTypeWithOld)
New->setType(MergedT);
}
static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
LookupResult &Previous) {
// C11 6.2.7p4:
// For an identifier with internal or external linkage declared
// in a scope in which a prior declaration of that identifier is
// visible, if the prior declaration specifies internal or
// external linkage, the type of the identifier at the later
// declaration becomes the composite type.
//
// If the variable isn't visible, we do not merge with its type.
if (Previous.isShadowed())
return false;
if (S.getLangOpts().CPlusPlus) {
// C++11 [dcl.array]p3:
// If there is a preceding declaration of the entity in the same
// scope in which the bound was specified, an omitted array bound
// is taken to be the same as in that earlier declaration.
return NewVD->isPreviousDeclInSameBlockScope() ||
(!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
!NewVD->getLexicalDeclContext()->isFunctionOrMethod());
} else {
// If the old declaration was function-local, don't merge with its
// type unless we're in the same function.
return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
}
}
/// MergeVarDecl - We just parsed a variable 'New' which has the same name
/// and scope as a previous declaration 'Old'. Figure out how to resolve this
/// situation, merging decls or emitting diagnostics as appropriate.
///
/// Tentative definition rules (C99 6.9.2p2) are checked by
/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
/// definitions here, since the initializer hasn't been attached.
///
void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
// If the new decl is already invalid, don't do any other checking.
if (New->isInvalidDecl())
return;
if (!shouldLinkPossiblyHiddenDecl(Previous, New))
return;
VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
// Verify the old decl was also a variable or variable template.
VarDecl *Old = nullptr;
VarTemplateDecl *OldTemplate = nullptr;
if (Previous.isSingleResult()) {
if (NewTemplate) {
OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
if (auto *Shadow =
dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate))
return New->setInvalidDecl();
} else {
Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
if (auto *Shadow =
dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New))
return New->setInvalidDecl();
}
}
if (!Old) {
Diag(New->getLocation(), diag::err_redefinition_different_kind)
<< New->getDeclName();
Diag(Previous.getRepresentativeDecl()->getLocation(),
diag::note_previous_definition);
return New->setInvalidDecl();
}
// Ensure the template parameters are compatible.
if (NewTemplate &&
!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
OldTemplate->getTemplateParameters(),
/*Complain=*/true, TPL_TemplateMatch))
return New->setInvalidDecl();
// C++ [class.mem]p1:
// A member shall not be declared twice in the member-specification [...]
//
// Here, we need only consider static data members.
if (Old->isStaticDataMember() && !New->isOutOfLine()) {
Diag(New->getLocation(), diag::err_duplicate_member)
<< New->getIdentifier();
Diag(Old->getLocation(), diag::note_previous_declaration);
New->setInvalidDecl();
}
mergeDeclAttributes(New, Old);
// Warn if an already-declared variable is made a weak_import in a subsequent
// declaration
if (New->hasAttr<WeakImportAttr>() &&
Old->getStorageClass() == SC_None &&
!Old->hasAttr<WeakImportAttr>()) {
Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
Diag(Old->getLocation(), diag::note_previous_definition);
// Remove weak_import attribute on new declaration.
New->dropAttr<WeakImportAttr>();
}
if (New->hasAttr<InternalLinkageAttr>() &&
!Old->hasAttr<InternalLinkageAttr>()) {
Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
<< New->getDeclName();
Diag(Old->getLocation(), diag::note_previous_definition);
New->dropAttr<InternalLinkageAttr>();
}
// Merge the types.
VarDecl *MostRecent = Old->getMostRecentDecl();
if (MostRecent != Old) {
MergeVarDeclTypes(New, MostRecent,
mergeTypeWithPrevious(*this, New, MostRecent, Previous));
if (New->isInvalidDecl())
return;
}
MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
if (New->isInvalidDecl())
return;
diag::kind PrevDiag;
SourceLocation OldLocation;
std::tie(PrevDiag, OldLocation) =
getNoteDiagForInvalidRedeclaration(Old, New);
// [dcl.stc]p8: Check if we have a non-static decl followed by a static.
if (New->getStorageClass() == SC_Static &&
!New->isStaticDataMember() &&
Old->hasExternalFormalLinkage()) {
if (getLangOpts().MicrosoftExt) {
Diag(New->getLocation(), diag::ext_static_non_static)
<< New->getDeclName();
Diag(OldLocation, PrevDiag);
} else {
Diag(New->getLocation(), diag::err_static_non_static)
<< New->getDeclName();
Diag(OldLocation, PrevDiag);
return New->setInvalidDecl();
}
}
// C99 6.2.2p4:
// For an identifier declared with the storage-class specifier
// extern in a scope in which a prior declaration of that
// identifier is visible,23) if the prior declaration specifies
// internal or external linkage, the linkage of the identifier at
// the later declaration is the same as the linkage specified at
// the prior declaration. If no prior declaration is visible, or
// if the prior declaration specifies no linkage, then the
// identifier has external linkage.
if (New->hasExternalStorage() && Old->hasLinkage())
/* Okay */;
else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
!New->isStaticDataMember() &&
Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
Diag(OldLocation, PrevDiag);
return New->setInvalidDecl();
}
// Check if extern is followed by non-extern and vice-versa.
if (New->hasExternalStorage() &&
!Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
Diag(OldLocation, PrevDiag);
return New->setInvalidDecl();
}
if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
!New->hasExternalStorage()) {
Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
Diag(OldLocation, PrevDiag);
return New->setInvalidDecl();
}
// Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
// FIXME: The test for external storage here seems wrong? We still
// need to check for mismatches.
if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
// Don't complain about out-of-line definitions of static members.
!(Old->getLexicalDeclContext()->isRecord() &&
!New->getLexicalDeclContext()->isRecord())) {
Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
Diag(OldLocation, PrevDiag);
return New->setInvalidDecl();
}
if (New->getTLSKind() != Old->getTLSKind()) {
if (!Old->getTLSKind()) {
Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
Diag(OldLocation, PrevDiag);
} else if (!New->getTLSKind()) {
Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
Diag(OldLocation, PrevDiag);
} else {
// Do not allow redeclaration to change the variable between requiring
// static and dynamic initialization.
// FIXME: GCC allows this, but uses the TLS keyword on the first
// declaration to determine the kind. Do we need to be compatible here?
Diag(New->getLocation(), diag::err_thread_thread_different_kind)
<< New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
Diag(OldLocation, PrevDiag);
}
}
// C++ doesn't have tentative definitions, so go right ahead and check here.
VarDecl *Def;
if (getLangOpts().CPlusPlus &&
New->isThisDeclarationADefinition() == VarDecl::Definition &&
(Def = Old->getDefinition())) {
NamedDecl *Hidden = nullptr;
if (!hasVisibleDefinition(Def, &Hidden) &&
(New->getFormalLinkage() == InternalLinkage ||
New->getDescribedVarTemplate() ||
New->getNumTemplateParameterLists() ||
New->getDeclContext()->isDependentContext())) {
// The previous definition is hidden, and multiple definitions are
// permitted (in separate TUs). Form another definition of it.
} else {
Diag(New->getLocation(), diag::err_redefinition) << New;
Diag(Def->getLocation(), diag::note_previous_definition);
New->setInvalidDecl();
return;
}
}
if (haveIncompatibleLanguageLinkages(Old, New)) {
Diag(New->getLocation(), diag::err_different_language_linkage) << New;
Diag(OldLocation, PrevDiag);
New->setInvalidDecl();
return;
}
// Merge "used" flag.
if (Old->getMostRecentDecl()->isUsed(false))
New->setIsUsed();
// Keep a chain of previous declarations.
New->setPreviousDecl(Old);
if (NewTemplate)
NewTemplate->setPreviousDecl(OldTemplate);
// Inherit access appropriately.
New->setAccess(Old->getAccess());
if (NewTemplate)
NewTemplate->setAccess(New->getAccess());
}
/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
/// no declarator (e.g. "struct foo;") is parsed.
Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
DeclSpec &DS) {
return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg());
}
// The MS ABI changed between VS2013 and VS2015 with regard to numbers used to
// disambiguate entities defined in different scopes.
// While the VS2015 ABI fixes potential miscompiles, it is also breaks
// compatibility.
// We will pick our mangling number depending on which version of MSVC is being
// targeted.
static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) {
return LO.isCompatibleWithMSVC(LangOptions::MSVC2015)
? S->getMSCurManglingNumber()
: S->getMSLastManglingNumber();
}
void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
if (!Context.getLangOpts().CPlusPlus)
return;
if (isa<CXXRecordDecl>(Tag->getParent())) {
// If this tag is the direct child of a class, number it if
// it is anonymous.
if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
return;
MangleNumberingContext &MCtx =
Context.getManglingNumberContext(Tag->getParent());
Context.setManglingNumber(
Tag, MCtx.getManglingNumber(
Tag, getMSManglingNumber(getLangOpts(), TagScope)));
return;
}
// If this tag isn't a direct child of a class, number it if it is local.
Decl *ManglingContextDecl;
if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
Tag->getDeclContext(), ManglingContextDecl)) {
Context.setManglingNumber(
Tag, MCtx->getManglingNumber(
Tag, getMSManglingNumber(getLangOpts(), TagScope)));
}
}
void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
TypedefNameDecl *NewTD) {
if (TagFromDeclSpec->isInvalidDecl())
return;
// Do nothing if the tag already has a name for linkage purposes.
if (TagFromDeclSpec->hasNameForLinkage())
return;
// A well-formed anonymous tag must always be a TUK_Definition.
assert(TagFromDeclSpec->isThisDeclarationADefinition());
// The type must match the tag exactly; no qualifiers allowed.
if (!Context.hasSameType(NewTD->getUnderlyingType(),
Context.getTagDeclType(TagFromDeclSpec))) {
if (getLangOpts().CPlusPlus)
Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD);
return;
}
// If we've already computed linkage for the anonymous tag, then
// adding a typedef name for the anonymous decl can change that
// linkage, which might be a serious problem. Diagnose this as
// unsupported and ignore the typedef name. TODO: we should
// pursue this as a language defect and establish a formal rule
// for how to handle it.
if (TagFromDeclSpec->hasLinkageBeenComputed()) {
Diag(NewTD->getLocation(), diag::err_typedef_changes_linkage);
SourceLocation tagLoc = TagFromDeclSpec->getInnerLocStart();
tagLoc = getLocForEndOfToken(tagLoc);
llvm::SmallString<40> textToInsert;
textToInsert += ' ';
textToInsert += NewTD->getIdentifier()->getName();
Diag(tagLoc, diag::note_typedef_changes_linkage)
<< FixItHint::CreateInsertion(tagLoc, textToInsert);
return;
}
// Otherwise, set this is the anon-decl typedef for the tag.
TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
}
static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) {
switch (T) {
case DeclSpec::TST_class:
return 0;
case DeclSpec::TST_struct:
return 1;
case DeclSpec::TST_interface:
return 2;
case DeclSpec::TST_union:
return 3;
case DeclSpec::TST_enum:
return 4;
default:
llvm_unreachable("unexpected type specifier");
}
}
/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
/// no declarator (e.g. "struct foo;") is parsed. It also accepts template
/// parameters to cope with template friend declarations.
Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
DeclSpec &DS,
MultiTemplateParamsArg TemplateParams,
bool IsExplicitInstantiation) {
Decl *TagD = nullptr;
TagDecl *Tag = nullptr;
if (DS.getTypeSpecType() == DeclSpec::TST_class ||
DS.getTypeSpecType() == DeclSpec::TST_struct ||
DS.getTypeSpecType() == DeclSpec::TST_interface ||
DS.getTypeSpecType() == DeclSpec::TST_union ||
DS.getTypeSpecType() == DeclSpec::TST_enum) {
TagD = DS.getRepAsDecl();
if (!TagD) // We probably had an error
return nullptr;
// Note that the above type specs guarantee that the
// type rep is a Decl, whereas in many of the others
// it's a Type.
if (isa<TagDecl>(TagD))
Tag = cast<TagDecl>(TagD);
else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
Tag = CTD->getTemplatedDecl();
}
if (Tag) {
handleTagNumbering(Tag, S);
Tag->setFreeStanding();
if (Tag->isInvalidDecl())
return Tag;
}
if (unsigned TypeQuals = DS.getTypeQualifiers()) {
// Enforce C99 6.7.3p2: "Types other than pointer types derived from object
// or incomplete types shall not be restrict-qualified."
if (TypeQuals & DeclSpec::TQ_restrict)
Diag(DS.getRestrictSpecLoc(),
diag::err_typecheck_invalid_restrict_not_pointer_noarg)
<< DS.getSourceRange();
}
if (DS.isConstexprSpecified()) {
// C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
// and definitions of functions and variables.
if (Tag)
Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
<< GetDiagnosticTypeSpecifierID(DS.getTypeSpecType());
else
Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators);
// Don't emit warnings after this error.
return TagD;
}
if (DS.isConceptSpecified()) {
// C++ Concepts TS [dcl.spec.concept]p1: A concept definition refers to
// either a function concept and its definition or a variable concept and
// its initializer.
Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
return TagD;
}
DiagnoseFunctionSpecifiers(DS);
if (DS.isFriendSpecified()) {
// If we're dealing with a decl but not a TagDecl, assume that
// whatever routines created it handled the friendship aspect.
if (TagD && !Tag)
return nullptr;
return ActOnFriendTypeDecl(S, DS, TemplateParams);
}
const CXXScopeSpec &SS = DS.getTypeSpecScope();
bool IsExplicitSpecialization =
!TemplateParams.empty() && TemplateParams.back()->size() == 0;
if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
!IsExplicitInstantiation && !IsExplicitSpecialization &&
!isa<ClassTemplatePartialSpecializationDecl>(Tag)) {
// Per C++ [dcl.type.elab]p1, a class declaration cannot have a
// nested-name-specifier unless it is an explicit instantiation
// or an explicit specialization.
//
// FIXME: We allow class template partial specializations here too, per the
// obvious intent of DR1819.
//
// Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
<< GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange();
return nullptr;
}
// Track whether this decl-specifier declares anything.
bool DeclaresAnything = true;
// Handle anonymous struct definitions.
if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
if (!Record->getDeclName() && Record->isCompleteDefinition() &&
DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
if (getLangOpts().CPlusPlus ||
Record->getDeclContext()->isRecord())
return BuildAnonymousStructOrUnion(S, DS, AS, Record,
Context.getPrintingPolicy());
DeclaresAnything = false;
}
}
// C11 6.7.2.1p2:
// A struct-declaration that does not declare an anonymous structure or
// anonymous union shall contain a struct-declarator-list.
//
// This rule also existed in C89 and C99; the grammar for struct-declaration
// did not permit a struct-declaration without a struct-declarator-list.
if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
// Check for Microsoft C extension: anonymous struct/union member.
// Handle 2 kinds of anonymous struct/union:
// struct STRUCT;
// union UNION;
// and
// STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
// UNION_TYPE; <- where UNION_TYPE is a typedef union.
if ((Tag && Tag->getDeclName()) ||
DS.getTypeSpecType() == DeclSpec::TST_typename) {
RecordDecl *Record = nullptr;
if (Tag)
Record = dyn_cast<RecordDecl>(Tag);
else if (const RecordType *RT =
DS.getRepAsType().get()->getAsStructureType())
Record = RT->getDecl();
else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
Record = UT->getDecl();
if (Record && getLangOpts().MicrosoftExt) {
Diag(DS.getLocStart(), diag::ext_ms_anonymous_record)
<< Record->isUnion() << DS.getSourceRange();
return BuildMicrosoftCAnonymousStruct(S, DS, Record);
}
DeclaresAnything = false;
}
}
// Skip all the checks below if we have a type error.
if (DS.getTypeSpecType() == DeclSpec::TST_error ||
(TagD && TagD->isInvalidDecl()))
return TagD;
if (getLangOpts().CPlusPlus &&
DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
if (Enum->enumerator_begin() == Enum->enumerator_end() &&
!Enum->getIdentifier() && !Enum->isInvalidDecl())
DeclaresAnything = false;
if (!DS.isMissingDeclaratorOk()) {
// Customize diagnostic for a typedef missing a name.
if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
Diag(DS.getLocStart(), diag::ext_typedef_without_a_name)
<< DS.getSourceRange();
else
DeclaresAnything = false;
}
if (DS.isModulePrivateSpecified() &&
Tag && Tag->getDeclContext()->isFunctionOrMethod())
Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
<< Tag->getTagKind()
<< FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
ActOnDocumentableDecl(TagD);
// C 6.7/2:
// A declaration [...] shall declare at least a declarator [...], a tag,
// or the members of an enumeration.
// C++ [dcl.dcl]p3:
// [If there are no declarators], and except for the declaration of an
// unnamed bit-field, the decl-specifier-seq shall introduce one or more
// names into the program, or shall redeclare a name introduced by a
// previous declaration.
if (!DeclaresAnything) {
// In C, we allow this as a (popular) extension / bug. Don't bother
// producing further diagnostics for redundant qualifiers after this.
Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange();
return TagD;
}
// C++ [dcl.stc]p1:
// If a storage-class-specifier appears in a decl-specifier-seq, [...] the
// init-declarator-list of the declaration shall not be empty.
// C++ [dcl.fct.spec]p1:
// If a cv-qualifier appears in a decl-specifier-seq, the
// init-declarator-list of the declaration shall not be empty.
//
// Spurious qualifiers here appear to be valid in C.
unsigned DiagID = diag::warn_standalone_specifier;
if (getLangOpts().CPlusPlus)
DiagID = diag::ext_standalone_specifier;
// Note that a linkage-specification sets a storage class, but
// 'extern "C" struct foo;' is actually valid and not theoretically
// useless.
if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
if (SCS == DeclSpec::SCS_mutable)
// Since mutable is not a viable storage class specifier in C, there is
// no reason to treat it as an extension. Instead, diagnose as an error.
Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
Diag(DS.getStorageClassSpecLoc(), DiagID)
<< DeclSpec::getSpecifierName(SCS);
}
if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
<< DeclSpec::getSpecifierName(TSCS);
if (DS.getTypeQualifiers()) {
if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
Diag(DS.getConstSpecLoc(), DiagID) << "const";
if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
// Restrict is covered above.
if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
}
// Warn about ignored type attributes, for example:
// __attribute__((aligned)) struct A;
// Attributes should be placed after tag to apply to type declaration.
if (!DS.getAttributes().empty()) {
DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
if (TypeSpecType == DeclSpec::TST_class ||
TypeSpecType == DeclSpec::TST_struct ||
TypeSpecType == DeclSpec::TST_interface ||
TypeSpecType == DeclSpec::TST_union ||
TypeSpecType == DeclSpec::TST_enum) {
for (AttributeList* attrs = DS.getAttributes().getList(); attrs;
attrs = attrs->getNext())
Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored)
<< attrs->getName() << GetDiagnosticTypeSpecifierID(TypeSpecType);
}
}
return TagD;
}
/// We are trying to inject an anonymous member into the given scope;
/// check if there's an existing declaration that can't be overloaded.
///
/// \return true if this is a forbidden redeclaration
static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
Scope *S,
DeclContext *Owner,
DeclarationName Name,
SourceLocation NameLoc,
bool IsUnion) {
LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
Sema::ForRedeclaration);
if (!SemaRef.LookupName(R, S)) return false;
if (R.getAsSingle<TagDecl>())
return false;
// Pick a representative declaration.
NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
assert(PrevDecl && "Expected a non-null Decl");
if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
return false;
SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl)
<< IsUnion << Name;
SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
return true;
}
/// InjectAnonymousStructOrUnionMembers - Inject the members of the
/// anonymous struct or union AnonRecord into the owning context Owner
/// and scope S. This routine will be invoked just after we realize
/// that an unnamed union or struct is actually an anonymous union or
/// struct, e.g.,
///
/// @code
/// union {
/// int i;
/// float f;
/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
/// // f into the surrounding scope.x
/// @endcode
///
/// This routine is recursive, injecting the names of nested anonymous
/// structs/unions into the owning context and scope as well.
static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S,
DeclContext *Owner,
RecordDecl *AnonRecord,
AccessSpecifier AS,
SmallVectorImpl<NamedDecl *> &Chaining,
bool MSAnonStruct) {
bool Invalid = false;
// Look every FieldDecl and IndirectFieldDecl with a name.
for (auto *D : AnonRecord->decls()) {
if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
cast<NamedDecl>(D)->getDeclName()) {
ValueDecl *VD = cast<ValueDecl>(D);
if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
VD->getLocation(),
AnonRecord->isUnion())) {
// C++ [class.union]p2:
// The names of the members of an anonymous union shall be
// distinct from the names of any other entity in the
// scope in which the anonymous union is declared.
Invalid = true;
} else {
// C++ [class.union]p2:
// For the purpose of name lookup, after the anonymous union
// definition, the members of the anonymous union are
// considered to have been defined in the scope in which the
// anonymous union is declared.
unsigned OldChainingSize = Chaining.size();
if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
Chaining.append(IF->chain_begin(), IF->chain_end());
else
Chaining.push_back(VD);
assert(Chaining.size() >= 2);
NamedDecl **NamedChain =
new (SemaRef.Context)NamedDecl*[Chaining.size()];
for (unsigned i = 0; i < Chaining.size(); i++)
NamedChain[i] = Chaining[i];
IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
VD->getType(), NamedChain, Chaining.size());
for (const auto *Attr : VD->attrs())
IndirectField->addAttr(Attr->clone(SemaRef.Context));
IndirectField->setAccess(AS);
IndirectField->setImplicit();
SemaRef.PushOnScopeChains(IndirectField, S);
// That includes picking up the appropriate access specifier.
if (AS != AS_none) IndirectField->setAccess(AS);
Chaining.resize(OldChainingSize);
}
}
}
return Invalid;
}
/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
/// a VarDecl::StorageClass. Any error reporting is up to the caller:
/// illegal input values are mapped to SC_None.
static StorageClass
StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
assert(StorageClassSpec != DeclSpec::SCS_typedef &&
"Parser allowed 'typedef' as storage class VarDecl.");
switch (StorageClassSpec) {
case DeclSpec::SCS_unspecified: return SC_None;
case DeclSpec::SCS_extern:
if (DS.isExternInLinkageSpec())
return SC_None;
return SC_Extern;
case DeclSpec::SCS_static: return SC_Static;
case DeclSpec::SCS_auto: return SC_Auto;
case DeclSpec::SCS_register: return SC_Register;
case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
// Illegal SCSs map to None: error reporting is up to the caller.
case DeclSpec::SCS_mutable: // Fall through.
case DeclSpec::SCS_typedef: return SC_None;
}
llvm_unreachable("unknown storage class specifier");
}
static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
assert(Record->hasInClassInitializer());
for (const auto *I : Record->decls()) {
const auto *FD = dyn_cast<FieldDecl>(I);
if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
FD = IFD->getAnonField();
if (FD && FD->hasInClassInitializer())
return FD->getLocation();
}
llvm_unreachable("couldn't find in-class initializer");
}
static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
SourceLocation DefaultInitLoc) {
if (!Parent->isUnion() || !Parent->hasInClassInitializer())
return;
S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
}
static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
CXXRecordDecl *AnonUnion) {
if (!Parent->isUnion() || !Parent->hasInClassInitializer())
return;
checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
}
/// BuildAnonymousStructOrUnion - Handle the declaration of an
/// anonymous structure or union. Anonymous unions are a C++ feature
/// (C++ [class.union]) and a C11 feature; anonymous structures
/// are a C11 feature and GNU C++ extension.
Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
AccessSpecifier AS,
RecordDecl *Record,
const PrintingPolicy &Policy) {
DeclContext *Owner = Record->getDeclContext();
// Diagnose whether this anonymous struct/union is an extension.
if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
Diag(Record->getLocation(), diag::ext_anonymous_union);
else if (!Record->isUnion() && getLangOpts().CPlusPlus)
Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
else if (!Record->isUnion() && !getLangOpts().C11)
Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
// C and C++ require different kinds of checks for anonymous
// structs/unions.
bool Invalid = false;
if (getLangOpts().CPlusPlus) {
const char *PrevSpec = nullptr;
unsigned DiagID;
if (Record->isUnion()) {
// C++ [class.union]p6:
// Anonymous unions declared in a named namespace or in the
// global namespace shall be declared static.
if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
(isa<TranslationUnitDecl>(Owner) ||
(isa<NamespaceDecl>(Owner) &&
cast<NamespaceDecl>(Owner)->getDeclName()))) {
Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
<< FixItHint::CreateInsertion(Record->getLocation(), "static ");
// Recover by adding 'static'.
DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
PrevSpec, DiagID, Policy);
}
// C++ [class.union]p6:
// A storage class is not allowed in a declaration of an
// anonymous union in a class scope.
else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
isa<RecordDecl>(Owner)) {
Diag(DS.getStorageClassSpecLoc(),
diag::err_anonymous_union_with_storage_spec)
<< FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
// Recover by removing the storage specifier.
DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
SourceLocation(),
PrevSpec, DiagID, Context.getPrintingPolicy());
}
}
// Ignore const/volatile/restrict qualifiers.
if (DS.getTypeQualifiers()) {
if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
<< Record->isUnion() << "const"
<< FixItHint::CreateRemoval(DS.getConstSpecLoc());
if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
Diag(DS.getVolatileSpecLoc(),
diag::ext_anonymous_struct_union_qualified)
<< Record->isUnion() << "volatile"
<< FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
Diag(DS.getRestrictSpecLoc(),
diag::ext_anonymous_struct_union_qualified)
<< Record->isUnion() << "restrict"
<< FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
Diag(DS.getAtomicSpecLoc(),
diag::ext_anonymous_struct_union_qualified)
<< Record->isUnion() << "_Atomic"
<< FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
DS.ClearTypeQualifiers();
}
// C++ [class.union]p2:
// The member-specification of an anonymous union shall only
// define non-static data members. [Note: nested types and
// functions cannot be declared within an anonymous union. ]
for (auto *Mem : Record->decls()) {
if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
// C++ [class.union]p3:
// An anonymous union shall not have private or protected
// members (clause 11).
assert(FD->getAccess() != AS_none);
if (FD->getAccess() != AS_public) {
Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
<< Record->isUnion() << (FD->getAccess() == AS_protected);
Invalid = true;
}
// C++ [class.union]p1
// An object of a class with a non-trivial constructor, a non-trivial
// copy constructor, a non-trivial destructor, or a non-trivial copy
// assignment operator cannot be a member of a union, nor can an
// array of such objects.
if (CheckNontrivialField(FD))
Invalid = true;
} else if (Mem->isImplicit()) {
// Any implicit members are fine.
} else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
// This is a type that showed up in an
// elaborated-type-specifier inside the anonymous struct or
// union, but which actually declares a type outside of the
// anonymous struct or union. It's okay.
} else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
if (!MemRecord->isAnonymousStructOrUnion() &&
MemRecord->getDeclName()) {
// Visual C++ allows type definition in anonymous struct or union.
if (getLangOpts().MicrosoftExt)
Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
<< Record->isUnion();
else {
// This is a nested type declaration.
Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
<< Record->isUnion();
Invalid = true;
}
} else {
// This is an anonymous type definition within another anonymous type.
// This is a popular extension, provided by Plan9, MSVC and GCC, but
// not part of standard C++.
Diag(MemRecord->getLocation(),
diag::ext_anonymous_record_with_anonymous_type)
<< Record->isUnion();
}
} else if (isa<AccessSpecDecl>(Mem)) {
// Any access specifier is fine.
} else if (isa<StaticAssertDecl>(Mem)) {
// In C++1z, static_assert declarations are also fine.
} else {
// We have something that isn't a non-static data
// member. Complain about it.
unsigned DK = diag::err_anonymous_record_bad_member;
if (isa<TypeDecl>(Mem))
DK = diag::err_anonymous_record_with_type;
else if (isa<FunctionDecl>(Mem))
DK = diag::err_anonymous_record_with_function;
else if (isa<VarDecl>(Mem))
DK = diag::err_anonymous_record_with_static;
// Visual C++ allows type definition in anonymous struct or union.
if (getLangOpts().MicrosoftExt &&
DK == diag::err_anonymous_record_with_type)
Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
<< Record->isUnion();
else {
Diag(Mem->getLocation(), DK) << Record->isUnion();
Invalid = true;
}
}
}
// C++11 [class.union]p8 (DR1460):
// At most one variant member of a union may have a
// brace-or-equal-initializer.
if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
Owner->isRecord())
checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
cast<CXXRecordDecl>(Record));
}
if (!Record->isUnion() && !Owner->isRecord()) {
Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
<< getLangOpts().CPlusPlus;
Invalid = true;
}
// Mock up a declarator.
Declarator Dc(DS, Declarator::MemberContext);
TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
assert(TInfo && "couldn't build declarator info for anonymous struct/union");
// Create a declaration for this anonymous struct/union.
NamedDecl *Anon = nullptr;
if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
Anon = FieldDecl::Create(Context, OwningClass,
DS.getLocStart(),
Record->getLocation(),
/*IdentifierInfo=*/nullptr,
Context.getTypeDeclType(Record),
TInfo,
/*BitWidth=*/nullptr, /*Mutable=*/false,
/*InitStyle=*/ICIS_NoInit);
Anon->setAccess(AS);
if (getLangOpts().CPlusPlus)
FieldCollector->Add(cast<FieldDecl>(Anon));
} else {
DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
if (SCSpec == DeclSpec::SCS_mutable) {
// mutable can only appear on non-static class members, so it's always
// an error here
Diag(Record->getLocation(), diag::err_mutable_nonmember);
Invalid = true;
SC = SC_None;
}
Anon = VarDecl::Create(Context, Owner,
DS.getLocStart(),
Record->getLocation(), /*IdentifierInfo=*/nullptr,
Context.getTypeDeclType(Record),
TInfo, SC);
// Default-initialize the implicit variable. This initialization will be
// trivial in almost all cases, except if a union member has an in-class
// initializer:
// union { int n = 0; };
ActOnUninitializedDecl(Anon, /*TypeMayContainAuto=*/false);
}
Anon->setImplicit();
// Mark this as an anonymous struct/union type.
Record->setAnonymousStructOrUnion(true);
// Add the anonymous struct/union object to the current
// context. We'll be referencing this object when we refer to one of
// its members.
Owner->addDecl(Anon);
// Inject the members of the anonymous struct/union into the owning
// context and into the identifier resolver chain for name lookup
// purposes.
SmallVector<NamedDecl*, 2> Chain;
Chain.push_back(Anon);
if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS,
Chain, false))
Invalid = true;
if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
Decl *ManglingContextDecl;
if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
NewVD->getDeclContext(), ManglingContextDecl)) {
Context.setManglingNumber(
NewVD, MCtx->getManglingNumber(
NewVD, getMSManglingNumber(getLangOpts(), S)));
Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
}
}
}
if (Invalid)
Anon->setInvalidDecl();
return Anon;
}
/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
/// Microsoft C anonymous structure.
/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
/// Example:
///
/// struct A { int a; };
/// struct B { struct A; int b; };
///
/// void foo() {
/// B var;
/// var.a = 3;
/// }
///
Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
RecordDecl *Record) {
assert(Record && "expected a record!");
// Mock up a declarator.
Declarator Dc(DS, Declarator::TypeNameContext);
TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
assert(TInfo && "couldn't build declarator info for anonymous struct");
auto *ParentDecl = cast<RecordDecl>(CurContext);
QualType RecTy = Context.getTypeDeclType(Record);
// Create a declaration for this anonymous struct.
NamedDecl *Anon = FieldDecl::Create(Context,
ParentDecl,
DS.getLocStart(),
DS.getLocStart(),
/*IdentifierInfo=*/nullptr,
RecTy,
TInfo,
/*BitWidth=*/nullptr, /*Mutable=*/false,
/*InitStyle=*/ICIS_NoInit);
Anon->setImplicit();
// Add the anonymous struct object to the current context.
CurContext->addDecl(Anon);
// Inject the members of the anonymous struct into the current
// context and into the identifier resolver chain for name lookup
// purposes.
SmallVector<NamedDecl*, 2> Chain;
Chain.push_back(Anon);
RecordDecl *RecordDef = Record->getDefinition();
if (RequireCompleteType(Anon->getLocation(), RecTy,
diag::err_field_incomplete) ||
InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
AS_none, Chain, true)) {
Anon->setInvalidDecl();
ParentDecl->setInvalidDecl();
}
return Anon;
}
/// GetNameForDeclarator - Determine the full declaration name for the
/// given Declarator.
DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
return GetNameFromUnqualifiedId(D.getName());
}
/// \brief Retrieves the declaration name from a parsed unqualified-id.
DeclarationNameInfo
Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
DeclarationNameInfo NameInfo;
NameInfo.setLoc(Name.StartLocation);
switch (Name.getKind()) {
case UnqualifiedId::IK_ImplicitSelfParam:
case UnqualifiedId::IK_Identifier:
NameInfo.setName(Name.Identifier);
NameInfo.setLoc(Name.StartLocation);
return NameInfo;
case UnqualifiedId::IK_OperatorFunctionId:
NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
Name.OperatorFunctionId.Operator));
NameInfo.setLoc(Name.StartLocation);
NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
= Name.OperatorFunctionId.SymbolLocations[0];
NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
= Name.EndLocation.getRawEncoding();
return NameInfo;
case UnqualifiedId::IK_LiteralOperatorId:
NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
Name.Identifier));
NameInfo.setLoc(Name.StartLocation);
NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
return NameInfo;
case UnqualifiedId::IK_ConversionFunctionId: {
TypeSourceInfo *TInfo;
QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
if (Ty.isNull())
return DeclarationNameInfo();
NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
Context.getCanonicalType(Ty)));
NameInfo.setLoc(Name.StartLocation);
NameInfo.setNamedTypeInfo(TInfo);
return NameInfo;
}
case UnqualifiedId::IK_ConstructorName: {
TypeSourceInfo *TInfo;
QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
if (Ty.isNull())
return DeclarationNameInfo();
NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
Context.getCanonicalType(Ty)));
NameInfo.setLoc(Name.StartLocation);
NameInfo.setNamedTypeInfo(TInfo);
return NameInfo;
}
case UnqualifiedId::IK_ConstructorTemplateId: {
// In well-formed code, we can only have a constructor
// template-id that refers to the current context, so go there
// to find the actual type being constructed.
CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
return DeclarationNameInfo();
// Determine the type of the class being constructed.
QualType CurClassType = Context.getTypeDeclType(CurClass);
// FIXME: Check two things: that the template-id names the same type as
// CurClassType, and that the template-id does not occur when the name
// was qualified.
NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
Context.getCanonicalType(CurClassType)));
NameInfo.setLoc(Name.StartLocation);
// FIXME: should we retrieve TypeSourceInfo?
NameInfo.setNamedTypeInfo(nullptr);
return NameInfo;
}
case UnqualifiedId::IK_DestructorName: {
TypeSourceInfo *TInfo;
QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
if (Ty.isNull())
return DeclarationNameInfo();
NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
Context.getCanonicalType(Ty)));
NameInfo.setLoc(Name.StartLocation);
NameInfo.setNamedTypeInfo(TInfo);
return NameInfo;
}
case UnqualifiedId::IK_TemplateId: {
TemplateName TName = Name.TemplateId->Template.get();
SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
return Context.getNameForTemplate(TName, TNameLoc);
}
} // switch (Name.getKind())
llvm_unreachable("Unknown name kind");
}
static QualType getCoreType(QualType Ty) {
do {
if (Ty->isPointerType() || Ty->isReferenceType())
Ty = Ty->getPointeeType();
else if (Ty->isArrayType())
Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
else
return Ty.withoutLocalFastQualifiers();
} while (true);
}
/// hasSimilarParameters - Determine whether the C++ functions Declaration
/// and Definition have "nearly" matching parameters. This heuristic is
/// used to improve diagnostics in the case where an out-of-line function
/// definition doesn't match any declaration within the class or namespace.
/// Also sets Params to the list of indices to the parameters that differ
/// between the declaration and the definition. If hasSimilarParameters
/// returns true and Params is empty, then all of the parameters match.
static bool hasSimilarParameters(ASTContext &Context,
FunctionDecl *Declaration,
FunctionDecl *Definition,
SmallVectorImpl<unsigned> &Params) {
Params.clear();
if (Declaration->param_size() != Definition->param_size())
return false;
for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
// The parameter types are identical
if (Context.hasSameType(DefParamTy, DeclParamTy))
continue;
QualType DeclParamBaseTy = getCoreType(DeclParamTy);
QualType DefParamBaseTy = getCoreType(DefParamTy);
const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
(DeclTyName && DeclTyName == DefTyName))
Params.push_back(Idx);
else // The two parameters aren't even close
return false;
}
return true;
}
/// NeedsRebuildingInCurrentInstantiation - Checks whether the given
/// declarator needs to be rebuilt in the current instantiation.
/// Any bits of declarator which appear before the name are valid for
/// consideration here. That's specifically the type in the decl spec
/// and the base type in any member-pointer chunks.
static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
DeclarationName Name) {
// The types we specifically need to rebuild are:
// - typenames, typeofs, and decltypes
// - types which will become injected class names
// Of course, we also need to rebuild any type referencing such a
// type. It's safest to just say "dependent", but we call out a
// few cases here.
DeclSpec &DS = D.getMutableDeclSpec();
switch (DS.getTypeSpecType()) {
case DeclSpec::TST_typename:
case DeclSpec::TST_typeofType:
case DeclSpec::TST_underlyingType:
case DeclSpec::TST_atomic: {
// Grab the type from the parser.
TypeSourceInfo *TSI = nullptr;
QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
if (T.isNull() || !T->isDependentType()) break;
// Make sure there's a type source info. This isn't really much
// of a waste; most dependent types should have type source info
// attached already.
if (!TSI)
TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
// Rebuild the type in the current instantiation.
TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
if (!TSI) return true;
// Store the new type back in the decl spec.
ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
DS.UpdateTypeRep(LocType);
break;
}
case DeclSpec::TST_decltype:
case DeclSpec::TST_typeofExpr: {
Expr *E = DS.getRepAsExpr();
ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
if (Result.isInvalid()) return true;
DS.UpdateExprRep(Result.get());
break;
}
default:
// Nothing to do for these decl specs.
break;
}
// It doesn't matter what order we do this in.
for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
DeclaratorChunk &Chunk = D.getTypeObject(I);
// The only type information in the declarator which can come
// before the declaration name is the base type of a member
// pointer.
if (Chunk.Kind != DeclaratorChunk::MemberPointer)
continue;
// Rebuild the scope specifier in-place.
CXXScopeSpec &SS = Chunk.Mem.Scope();
if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
return true;
}
return false;
}
Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
D.setFunctionDefinitionKind(FDK_Declaration);
Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
Dcl && Dcl->getDeclContext()->isFileContext())
Dcl->setTopLevelDeclInObjCContainer();
return Dcl;
}
/// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
/// If T is the name of a class, then each of the following shall have a
/// name different from T:
/// - every static data member of class T;
/// - every member function of class T
/// - every member of class T that is itself a type;
/// \returns true if the declaration name violates these rules.
bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
DeclarationNameInfo NameInfo) {
DeclarationName Name = NameInfo.getName();
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
if (Record->getIdentifier() && Record->getDeclName() == Name) {
Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
return true;
}
return false;
}
/// \brief Diagnose a declaration whose declarator-id has the given
/// nested-name-specifier.
///
/// \param SS The nested-name-specifier of the declarator-id.
///
/// \param DC The declaration context to which the nested-name-specifier
/// resolves.
///
/// \param Name The name of the entity being declared.
///
/// \param Loc The location of the name of the entity being declared.
///
/// \returns true if we cannot safely recover from this error, false otherwise.
bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
DeclarationName Name,
SourceLocation Loc) {
DeclContext *Cur = CurContext;
while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
Cur = Cur->getParent();
// If the user provided a superfluous scope specifier that refers back to the
// class in which the entity is already declared, diagnose and ignore it.
//
// class X {
// void X::f();
// };
//
// Note, it was once ill-formed to give redundant qualification in all
// contexts, but that rule was removed by DR482.
if (Cur->Equals(DC)) {
if (Cur->isRecord()) {
Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
: diag::err_member_extra_qualification)
<< Name << FixItHint::CreateRemoval(SS.getRange());
SS.clear();
} else {
Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
}
return false;
}
// Check whether the qualifying scope encloses the scope of the original
// declaration.
if (!Cur->Encloses(DC)) {
if (Cur->isRecord())
Diag(Loc, diag::err_member_qualification)
<< Name << SS.getRange();
else if (isa<TranslationUnitDecl>(DC))
Diag(Loc, diag::err_invalid_declarator_global_scope)
<< Name << SS.getRange();
else if (isa<FunctionDecl>(Cur))
Diag(Loc, diag::err_invalid_declarator_in_function)
<< Name << SS.getRange();
else if (isa<BlockDecl>(Cur))
Diag(Loc, diag::err_invalid_declarator_in_block)
<< Name << SS.getRange();
else
Diag(Loc, diag::err_invalid_declarator_scope)
<< Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
return true;
}
if (Cur->isRecord()) {
// Cannot qualify members within a class.
Diag(Loc, diag::err_member_qualification)
<< Name << SS.getRange();
SS.clear();
// C++ constructors and destructors with incorrect scopes can break
// our AST invariants by having the wrong underlying types. If
// that's the case, then drop this declaration entirely.
if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
Name.getNameKind() == DeclarationName::CXXDestructorName) &&
!Context.hasSameType(Name.getCXXNameType(),
Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
return true;
return false;
}
// C++11 [dcl.meaning]p1:
// [...] "The nested-name-specifier of the qualified declarator-id shall
// not begin with a decltype-specifer"
NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
while (SpecLoc.getPrefix())
SpecLoc = SpecLoc.getPrefix();
if (dyn_cast_or_null<DecltypeType>(
SpecLoc.getNestedNameSpecifier()->getAsType()))
Diag(Loc, diag::err_decltype_in_declarator)
<< SpecLoc.getTypeLoc().getSourceRange();
return false;
}
NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
MultiTemplateParamsArg TemplateParamLists) {
// TODO: consider using NameInfo for diagnostic.
DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
DeclarationName Name = NameInfo.getName();
// All of these full declarators require an identifier. If it doesn't have
// one, the ParsedFreeStandingDeclSpec action should be used.
if (!Name) {
if (!D.isInvalidType()) // Reject this if we think it is valid.
Diag(D.getDeclSpec().getLocStart(),
diag::err_declarator_need_ident)
<< D.getDeclSpec().getSourceRange() << D.getSourceRange();
return nullptr;
} else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
return nullptr;
// The scope passed in may not be a decl scope. Zip up the scope tree until
// we find one that is.
while ((S->getFlags() & Scope::DeclScope) == 0 ||
(S->getFlags() & Scope::TemplateParamScope) != 0)
S = S->getParent();
DeclContext *DC = CurContext;
if (D.getCXXScopeSpec().isInvalid())
D.setInvalidType();
else if (D.getCXXScopeSpec().isSet()) {
if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
UPPC_DeclarationQualifier))
return nullptr;
bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
if (!DC || isa<EnumDecl>(DC)) {
// If we could not compute the declaration context, it's because the
// declaration context is dependent but does not refer to a class,
// class template, or class template partial specialization. Complain
// and return early, to avoid the coming semantic disaster.
Diag(D.getIdentifierLoc(),
diag::err_template_qualified_declarator_no_match)
<< D.getCXXScopeSpec().getScopeRep()
<< D.getCXXScopeSpec().getRange();
return nullptr;
}
bool IsDependentContext = DC->isDependentContext();
if (!IsDependentContext &&
RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
return nullptr;
// If a class is incomplete, do not parse entities inside it.
if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
Diag(D.getIdentifierLoc(),
diag::err_member_def_undefined_record)
<< Name << DC << D.getCXXScopeSpec().getRange();
return nullptr;
}
if (!D.getDeclSpec().isFriendSpecified()) {
if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC,
Name, D.getIdentifierLoc())) {
if (DC->isRecord())
return nullptr;
D.setInvalidType();
}
}
// Check whether we need to rebuild the type of the given
// declaration in the current instantiation.
if (EnteringContext && IsDependentContext &&
TemplateParamLists.size() != 0) {
ContextRAII SavedContext(*this, DC);
if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
D.setInvalidType();
}
}
TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
QualType R = TInfo->getType();
if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo))
// If this is a typedef, we'll end up spewing multiple diagnostics.
// Just return early; it's safer. If this is a function, let the
// "constructor cannot have a return type" diagnostic handle it.
if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
return nullptr;
if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
UPPC_DeclarationType))
D.setInvalidType();
LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
ForRedeclaration);
// See if this is a redefinition of a variable in the same scope.
if (!D.getCXXScopeSpec().isSet()) {
bool IsLinkageLookup = false;
bool CreateBuiltins = false;
// If the declaration we're planning to build will be a function
// or object with linkage, then look for another declaration with
// linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
//
// If the declaration we're planning to build will be declared with
// external linkage in the translation unit, create any builtin with
// the same name.
if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
/* Do nothing*/;
else if (CurContext->isFunctionOrMethod() &&
(D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
R->isFunctionType())) {
IsLinkageLookup = true;
CreateBuiltins =
CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
} else if (CurContext->getRedeclContext()->isTranslationUnit() &&
D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
CreateBuiltins = true;
if (IsLinkageLookup)
Previous.clear(LookupRedeclarationWithLinkage);
LookupName(Previous, S, CreateBuiltins);
} else { // Something like "int foo::x;"
LookupQualifiedName(Previous, DC);
// C++ [dcl.meaning]p1:
// When the declarator-id is qualified, the declaration shall refer to a
// previously declared member of the class or namespace to which the
// qualifier refers (or, in the case of a namespace, of an element of the
// inline namespace set of that namespace (7.3.1)) or to a specialization
// thereof; [...]
//
// Note that we already checked the context above, and that we do not have
// enough information to make sure that Previous contains the declaration
// we want to match. For example, given:
//
// class X {
// void f();
// void f(float);
// };
//
// void X::f(int) { } // ill-formed
//
// In this case, Previous will point to the overload set
// containing the two f's declared in X, but neither of them
// matches.
// C++ [dcl.meaning]p1:
// [...] the member shall not merely have been introduced by a
// using-declaration in the scope of the class or namespace nominated by
// the nested-name-specifier of the declarator-id.
RemoveUsingDecls(Previous);
}
if (Previous.isSingleResult() &&
Previous.getFoundDecl()->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
if (!D.isInvalidType())
DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
Previous.getFoundDecl());
// Just pretend that we didn't see the previous declaration.
Previous.clear();
}
// In C++, the previous declaration we find might be a tag type
// (class or enum). In this case, the new declaration will hide the
// tag type. Note that this does does not apply if we're declaring a
// typedef (C++ [dcl.typedef]p4).
if (Previous.isSingleTagDecl() &&
D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
Previous.clear();
// Check that there are no default arguments other than in the parameters
// of a function declaration (C++ only).
if (getLangOpts().CPlusPlus)
CheckExtraCXXDefaultArguments(D);
if (D.getDeclSpec().isConceptSpecified()) {
// C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
// applied only to the definition of a function template or variable
// template, declared in namespace scope
if (!TemplateParamLists.size()) {
Diag(D.getDeclSpec().getConceptSpecLoc(),
diag:: err_concept_wrong_decl_kind);
return nullptr;
}
if (!DC->getRedeclContext()->isFileContext()) {
Diag(D.getIdentifierLoc(),
diag::err_concept_decls_may_only_appear_in_namespace_scope);
return nullptr;
}
}
NamedDecl *New;
bool AddToScope = true;
if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
if (TemplateParamLists.size()) {
Diag(D.getIdentifierLoc(), diag::err_template_typedef);
return nullptr;
}
New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
} else if (R->isFunctionType()) {
New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
TemplateParamLists,
AddToScope);
} else {
New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
AddToScope);
}
if (!New)
return nullptr;
// If this has an identifier and is not an invalid redeclaration or
// function template specialization, add it to the scope stack.
if (New->getDeclName() && AddToScope &&
!(D.isRedeclaration() && New->isInvalidDecl())) {
// Only make a locally-scoped extern declaration visible if it is the first
// declaration of this entity. Qualified lookup for such an entity should
// only find this declaration if there is no visible declaration of it.
bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl();
PushOnScopeChains(New, S, AddToContext);
if (!AddToContext)
CurContext->addHiddenDecl(New);
}
return New;
}
/// Helper method to turn variable array types into constant array
/// types in certain situations which would otherwise be errors (for
/// GCC compatibility).
static QualType TryToFixInvalidVariablyModifiedType(QualType T,
ASTContext &Context,
bool &SizeIsNegative,
llvm::APSInt &Oversized) {
// This method tries to turn a variable array into a constant
// array even when the size isn't an ICE. This is necessary
// for compatibility with code that depends on gcc's buggy
// constant expression folding, like struct {char x[(int)(char*)2];}
SizeIsNegative = false;
Oversized = 0;
if (T->isDependentType())
return QualType();
QualifierCollector Qs;
const Type *Ty = Qs.strip(T);
if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
QualType Pointee = PTy->getPointeeType();
QualType FixedType =
TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
Oversized);
if (FixedType.isNull()) return FixedType;
FixedType = Context.getPointerType(FixedType);
return Qs.apply(Context, FixedType);
}
if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
QualType Inner = PTy->getInnerType();
QualType FixedType =
TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
Oversized);
if (FixedType.isNull()) return FixedType;
FixedType = Context.getParenType(FixedType);
return Qs.apply(Context, FixedType);
}
const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
if (!VLATy)
return QualType();
// FIXME: We should probably handle this case
if (VLATy->getElementType()->isVariablyModifiedType())
return QualType();
llvm::APSInt Res;
if (!VLATy->getSizeExpr() ||
!VLATy->getSizeExpr()->EvaluateAsInt(Res, Context))
return QualType();
// Check whether the array size is negative.
if (Res.isSigned() && Res.isNegative()) {
SizeIsNegative = true;
return QualType();
}
// Check whether the array is too large to be addressed.
unsigned ActiveSizeBits
= ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
Res);
if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
Oversized = Res;
return QualType();
}
return Context.getConstantArrayType(VLATy->getElementType(),
Res, ArrayType::Normal, 0);
}
static void
FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
SrcTL = SrcTL.getUnqualifiedLoc();
DstTL = DstTL.getUnqualifiedLoc();
if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
DstPTL.getPointeeLoc());
DstPTL.setStarLoc(SrcPTL.getStarLoc());
return;
}
if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
DstPTL.getInnerLoc());
DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
return;
}
ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
TypeLoc SrcElemTL = SrcATL.getElementLoc();
TypeLoc DstElemTL = DstATL.getElementLoc();
DstElemTL.initializeFullCopy(SrcElemTL);
DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
DstATL.setSizeExpr(SrcATL.getSizeExpr());
DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
}
/// Helper method to turn variable array types into constant array
/// types in certain situations which would otherwise be errors (for
/// GCC compatibility).
static TypeSourceInfo*
TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
ASTContext &Context,
bool &SizeIsNegative,
llvm::APSInt &Oversized) {
QualType FixedTy
= TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
SizeIsNegative, Oversized);
if (FixedTy.isNull())
return nullptr;
TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
FixedTInfo->getTypeLoc());
return FixedTInfo;
}
/// \brief Register the given locally-scoped extern "C" declaration so
/// that it can be found later for redeclarations. We include any extern "C"
/// declaration that is not visible in the translation unit here, not just
/// function-scope declarations.
void
Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
if (!getLangOpts().CPlusPlus &&
ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
// Don't need to track declarations in the TU in C.
return;
// Note that we have a locally-scoped external with this name.
Context.getExternCContextDecl()->makeDeclVisibleInContext(ND);
}
NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
// FIXME: We can have multiple results via __attribute__((overloadable)).
auto Result = Context.getExternCContextDecl()->lookup(Name);
return Result.empty() ? nullptr : *Result.begin();
}
/// \brief Diagnose function specifiers on a declaration of an identifier that
/// does not identify a function.
void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
// FIXME: We should probably indicate the identifier in question to avoid
// confusion for constructs like "inline int a(), b;"
if (DS.isInlineSpecified())
Diag(DS.getInlineSpecLoc(),
diag::err_inline_non_function);
if (DS.isVirtualSpecified())
Diag(DS.getVirtualSpecLoc(),
diag::err_virtual_non_function);
if (DS.isExplicitSpecified())
Diag(DS.getExplicitSpecLoc(),
diag::err_explicit_non_function);
if (DS.isNoreturnSpecified())
Diag(DS.getNoreturnSpecLoc(),
diag::err_noreturn_non_function);
}
NamedDecl*
Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
TypeSourceInfo *TInfo, LookupResult &Previous) {
// Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
if (D.getCXXScopeSpec().isSet()) {
Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
<< D.getCXXScopeSpec().getRange();
D.setInvalidType();
// Pretend we didn't see the scope specifier.
DC = CurContext;
Previous.clear();
}
DiagnoseFunctionSpecifiers(D.getDeclSpec());
if (D.getDeclSpec().isConstexprSpecified())
Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
<< 1;
if (D.getDeclSpec().isConceptSpecified())
Diag(D.getDeclSpec().getConceptSpecLoc(),
diag::err_concept_wrong_decl_kind);
if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
<< D.getName().getSourceRange();
return nullptr;
}
TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
if (!NewTD) return nullptr;
// Handle attributes prior to checking for duplicates in MergeVarDecl
ProcessDeclAttributes(S, NewTD, D);
CheckTypedefForVariablyModifiedType(S, NewTD);
bool Redeclaration = D.isRedeclaration();
NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
D.setRedeclaration(Redeclaration);
return ND;
}
void
Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
// C99 6.7.7p2: If a typedef name specifies a variably modified type
// then it shall have block scope.
// Note that variably modified types must be fixed before merging the decl so
// that redeclarations will match.
TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
QualType T = TInfo->getType();
if (T->isVariablyModifiedType()) {
getCurFunction()->setHasBranchProtectedScope();
if (S->getFnParent() == nullptr) {
bool SizeIsNegative;
llvm::APSInt Oversized;
TypeSourceInfo *FixedTInfo =
TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
SizeIsNegative,
Oversized);
if (FixedTInfo) {
Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
NewTD->setTypeSourceInfo(FixedTInfo);
} else {
if (SizeIsNegative)
Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
else if (T->isVariableArrayType())
Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
else if (Oversized.getBoolValue())
Diag(NewTD->getLocation(), diag::err_array_too_large)
<< Oversized.toString(10);
else
Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
NewTD->setInvalidDecl();
}
}
}
}
/// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
/// declares a typedef-name, either using the 'typedef' type specifier or via
/// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
NamedDecl*
Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
LookupResult &Previous, bool &Redeclaration) {
// Merge the decl with the existing one if appropriate. If the decl is
// in an outer scope, it isn't the same thing.
FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
/*AllowInlineNamespace*/false);
filterNonConflictingPreviousTypedefDecls(*this, NewTD, Previous);
if (!Previous.empty()) {
Redeclaration = true;
MergeTypedefNameDecl(S, NewTD, Previous);
}
// If this is the C FILE type, notify the AST context.
if (IdentifierInfo *II = NewTD->getIdentifier())
if (!NewTD->isInvalidDecl() &&
NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
if (II->isStr("FILE"))
Context.setFILEDecl(NewTD);
else if (II->isStr("jmp_buf"))
Context.setjmp_bufDecl(NewTD);
else if (II->isStr("sigjmp_buf"))
Context.setsigjmp_bufDecl(NewTD);
else if (II->isStr("ucontext_t"))
Context.setucontext_tDecl(NewTD);
}
return NewTD;
}
/// \brief Determines whether the given declaration is an out-of-scope
/// previous declaration.
///
/// This routine should be invoked when name lookup has found a
/// previous declaration (PrevDecl) that is not in the scope where a
/// new declaration by the same name is being introduced. If the new
/// declaration occurs in a local scope, previous declarations with
/// linkage may still be considered previous declarations (C99
/// 6.2.2p4-5, C++ [basic.link]p6).
///
/// \param PrevDecl the previous declaration found by name
/// lookup
///
/// \param DC the context in which the new declaration is being
/// declared.
///
/// \returns true if PrevDecl is an out-of-scope previous declaration
/// for a new delcaration with the same name.
static bool
isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
ASTContext &Context) {
if (!PrevDecl)
return false;
if (!PrevDecl->hasLinkage())
return false;
if (Context.getLangOpts().CPlusPlus) {
// C++ [basic.link]p6:
// If there is a visible declaration of an entity with linkage
// having the same name and type, ignoring entities declared
// outside the innermost enclosing namespace scope, the block
// scope declaration declares that same entity and receives the
// linkage of the previous declaration.
DeclContext *OuterContext = DC->getRedeclContext();
if (!OuterContext->isFunctionOrMethod())
// This rule only applies to block-scope declarations.
return false;
DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
if (PrevOuterContext->isRecord())
// We found a member function: ignore it.
return false;
// Find the innermost enclosing namespace for the new and
// previous declarations.
OuterContext = OuterContext->getEnclosingNamespaceContext();
PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
// The previous declaration is in a different namespace, so it
// isn't the same function.
if (!OuterContext->Equals(PrevOuterContext))
return false;
}
return true;
}
static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) {
CXXScopeSpec &SS = D.getCXXScopeSpec();
if (!SS.isSet()) return;
DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext()));
}
bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
QualType type = decl->getType();
Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
if (lifetime == Qualifiers::OCL_Autoreleasing) {
// Various kinds of declaration aren't allowed to be __autoreleasing.
unsigned kind = -1U;
if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
if (var->hasAttr<BlocksAttr>())
kind = 0; // __block
else if (!var->hasLocalStorage())
kind = 1; // global
} else if (isa<ObjCIvarDecl>(decl)) {
kind = 3; // ivar
} else if (isa<FieldDecl>(decl)) {
kind = 2; // field
}
if (kind != -1U) {
Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
<< kind;
}
} else if (lifetime == Qualifiers::OCL_None) {
// Try to infer lifetime.
if (!type->isObjCLifetimeType())
return false;
lifetime = type->getObjCARCImplicitLifetime();
type = Context.getLifetimeQualifiedType(type, lifetime);
decl->setType(type);
}
if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
// Thread-local variables cannot have lifetime.
if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
var->getTLSKind()) {
Diag(var->getLocation(), diag::err_arc_thread_ownership)
<< var->getType();
return true;
}
}
return false;
}
static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
// Ensure that an auto decl is deduced otherwise the checks below might cache
// the wrong linkage.
assert(S.ParsingInitForAutoVars.count(&ND) == 0);
// 'weak' only applies to declarations with external linkage.
if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
if (!ND.isExternallyVisible()) {
S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
ND.dropAttr<WeakAttr>();
}
}
if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
if (ND.isExternallyVisible()) {
S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
ND.dropAttr<WeakRefAttr>();
ND.dropAttr<AliasAttr>();
}
}
if (auto *VD = dyn_cast<VarDecl>(&ND)) {
if (VD->hasInit()) {
if (const auto *Attr = VD->getAttr<AliasAttr>()) {
assert(VD->isThisDeclarationADefinition() &&
!VD->isExternallyVisible() && "Broken AliasAttr handled late!");
S.Diag(Attr->getLocation(), diag::err_alias_is_definition) << VD;
VD->dropAttr<AliasAttr>();
}
}
}
// 'selectany' only applies to externally visible variable declarations.
// It does not apply to functions.
if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
S.Diag(Attr->getLocation(),
diag::err_attribute_selectany_non_extern_data);
ND.dropAttr<SelectAnyAttr>();
}
}
if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
// dll attributes require external linkage. Static locals may have external
// linkage but still cannot be explicitly imported or exported.
auto *VD = dyn_cast<VarDecl>(&ND);
if (!ND.isExternallyVisible() || (VD && VD->isStaticLocal())) {
S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
<< &ND << Attr;
ND.setInvalidDecl();
}
}
// Virtual functions cannot be marked as 'notail'.
if (auto *Attr = ND.getAttr<NotTailCalledAttr>())
if (auto *MD = dyn_cast<CXXMethodDecl>(&ND))
if (MD->isVirtual()) {
S.Diag(ND.getLocation(),
diag::err_invalid_attribute_on_virtual_function)
<< Attr;
ND.dropAttr<NotTailCalledAttr>();
}
}
static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
NamedDecl *NewDecl,
bool IsSpecialization) {
if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl))
OldDecl = OldTD->getTemplatedDecl();
if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl))
NewDecl = NewTD->getTemplatedDecl();
if (!OldDecl || !NewDecl)
return;
const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
// dllimport and dllexport are inheritable attributes so we have to exclude
// inherited attribute instances.
bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
(NewExportAttr && !NewExportAttr->isInherited());
// A redeclaration is not allowed to add a dllimport or dllexport attribute,
// the only exception being explicit specializations.
// Implicitly generated declarations are also excluded for now because there
// is no other way to switch these to use dllimport or dllexport.
bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
// Allow with a warning for free functions and global variables.
bool JustWarn = false;
if (!OldDecl->isCXXClassMember()) {
auto *VD = dyn_cast<VarDecl>(OldDecl);
if (VD && !VD->getDescribedVarTemplate())
JustWarn = true;
auto *FD = dyn_cast<FunctionDecl>(OldDecl);
if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
JustWarn = true;
}
// We cannot change a declaration that's been used because IR has already
// been emitted. Dllimported functions will still work though (modulo
// address equality) as they can use the thunk.
if (OldDecl->isUsed())
if (!isa<FunctionDecl>(OldDecl) || !NewImportAttr)
JustWarn = false;
unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
: diag::err_attribute_dll_redeclaration;
S.Diag(NewDecl->getLocation(), DiagID)
<< NewDecl
<< (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
if (!JustWarn) {
NewDecl->setInvalidDecl();
return;
}
}
// A redeclaration is not allowed to drop a dllimport attribute, the only
// exceptions being inline function definitions, local extern declarations,
// and qualified friend declarations.
// NB: MSVC converts such a declaration to dllexport.
bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
if (const auto *VD = dyn_cast<VarDecl>(NewDecl))
// Ignore static data because out-of-line definitions are diagnosed
// separately.
IsStaticDataMember = VD->isStaticDataMember();
else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
IsInline = FD->isInlined();
IsQualifiedFriend = FD->getQualifier() &&
FD->getFriendObjectKind() == Decl::FOK_Declared;
}
if (OldImportAttr && !HasNewAttr && !IsInline && !IsStaticDataMember &&
!NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
S.Diag(NewDecl->getLocation(),
diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
<< NewDecl << OldImportAttr;
S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
OldDecl->dropAttr<DLLImportAttr>();
NewDecl->dropAttr<DLLImportAttr>();
} else if (IsInline && OldImportAttr &&
!S.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
// In MinGW, seeing a function declared inline drops the dllimport attribute.
OldDecl->dropAttr<DLLImportAttr>();
NewDecl->dropAttr<DLLImportAttr>();
S.Diag(NewDecl->getLocation(),
diag::warn_dllimport_dropped_from_inline_function)
<< NewDecl << OldImportAttr;
}
}
/// Given that we are within the definition of the given function,
/// will that definition behave like C99's 'inline', where the
/// definition is discarded except for optimization purposes?
static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
// Try to avoid calling GetGVALinkageForFunction.
// All cases of this require the 'inline' keyword.
if (!FD->isInlined()) return false;
// This is only possible in C++ with the gnu_inline attribute.
if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
return false;
// Okay, go ahead and call the relatively-more-expensive function.
#ifndef NDEBUG
// AST quite reasonably asserts that it's working on a function
// definition. We don't really have a way to tell it that we're
// currently defining the function, so just lie to it in +Asserts
// builds. This is an awful hack.
FD->setLazyBody(1);
#endif
bool isC99Inline =
S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
#ifndef NDEBUG
FD->setLazyBody(0);
#endif
return isC99Inline;
}
/// Determine whether a variable is extern "C" prior to attaching
/// an initializer. We can't just call isExternC() here, because that
/// will also compute and cache whether the declaration is externally
/// visible, which might change when we attach the initializer.
///
/// This can only be used if the declaration is known to not be a
/// redeclaration of an internal linkage declaration.
///
/// For instance:
///
/// auto x = []{};
///
/// Attaching the initializer here makes this declaration not externally
/// visible, because its type has internal linkage.
///
/// FIXME: This is a hack.
template<typename T>
static bool isIncompleteDeclExternC(Sema &S, const T *D) {
if (S.getLangOpts().CPlusPlus) {
// In C++, the overloadable attribute negates the effects of extern "C".
if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
return false;
// So do CUDA's host/device attributes if overloading is enabled.
if (S.getLangOpts().CUDA && S.getLangOpts().CUDATargetOverloads &&
(D->template hasAttr<CUDADeviceAttr>() ||
D->template hasAttr<CUDAHostAttr>()))
return false;
}
return D->isExternC();
}
static bool shouldConsiderLinkage(const VarDecl *VD) {
const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
if (DC->isFunctionOrMethod())
return VD->hasExternalStorage();
if (DC->isFileContext())
return true;
if (DC->isRecord())
return false;
llvm_unreachable("Unexpected context");
}
static bool shouldConsiderLinkage(const FunctionDecl *FD) {
const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
if (DC->isFileContext() || DC->isFunctionOrMethod())
return true;
if (DC->isRecord())
return false;
llvm_unreachable("Unexpected context");
}
static bool hasParsedAttr(Scope *S, const AttributeList *AttrList,
AttributeList::Kind Kind) {
for (const AttributeList *L = AttrList; L; L = L->getNext())
if (L->getKind() == Kind)
return true;
return false;
}
static bool hasParsedAttr(Scope *S, const Declarator &PD,
AttributeList::Kind Kind) {
// Check decl attributes on the DeclSpec.
if (hasParsedAttr(S, PD.getDeclSpec().getAttributes().getList(), Kind))
return true;
// Walk the declarator structure, checking decl attributes that were in a type
// position to the decl itself.
for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
if (hasParsedAttr(S, PD.getTypeObject(I).getAttrs(), Kind))
return true;
}
// Finally, check attributes on the decl itself.
return hasParsedAttr(S, PD.getAttributes(), Kind);
}
/// Adjust the \c DeclContext for a function or variable that might be a
/// function-local external declaration.
bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
if (!DC->isFunctionOrMethod())
return false;
// If this is a local extern function or variable declared within a function
// template, don't add it into the enclosing namespace scope until it is
// instantiated; it might have a dependent type right now.
if (DC->isDependentContext())
return true;
// C++11 [basic.link]p7:
// When a block scope declaration of an entity with linkage is not found to
// refer to some other declaration, then that entity is a member of the
// innermost enclosing namespace.
//
// Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
// semantically-enclosing namespace, not a lexically-enclosing one.
while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
DC = DC->getParent();
return true;
}
/// \brief Returns true if given declaration has external C language linkage.
static bool isDeclExternC(const Decl *D) {
if (const auto *FD = dyn_cast<FunctionDecl>(D))
return FD->isExternC();
if (const auto *VD = dyn_cast<VarDecl>(D))
return VD->isExternC();
llvm_unreachable("Unknown type of decl!");
}
NamedDecl *
Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
TypeSourceInfo *TInfo, LookupResult &Previous,
MultiTemplateParamsArg TemplateParamLists,
bool &AddToScope) {
QualType R = TInfo->getType();
DeclarationName Name = GetNameForDeclarator(D).getName();
DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
// dllimport globals without explicit storage class are treated as extern. We
// have to change the storage class this early to get the right DeclContext.
if (SC == SC_None && !DC->isRecord() &&
hasParsedAttr(S, D, AttributeList::AT_DLLImport) &&
!hasParsedAttr(S, D, AttributeList::AT_DLLExport))
SC = SC_Extern;
DeclContext *OriginalDC = DC;
bool IsLocalExternDecl = SC == SC_Extern &&
adjustContextForLocalExternDecl(DC);
if (getLangOpts().OpenCL) {
// OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
QualType NR = R;
while (NR->isPointerType()) {
if (NR->isFunctionPointerType()) {
Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer_variable);
D.setInvalidType();
break;
}
NR = NR->getPointeeType();
}
if (!getOpenCLOptions().cl_khr_fp16) {
// OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
// half array type (unless the cl_khr_fp16 extension is enabled).
if (Context.getBaseElementType(R)->isHalfType()) {
Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
D.setInvalidType();
}
}
}
if (SCSpec == DeclSpec::SCS_mutable) {
// mutable can only appear on non-static class members, so it's always
// an error here
Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
D.setInvalidType();
SC = SC_None;
}
if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
!D.getAsmLabel() && !getSourceManager().isInSystemMacro(
D.getDeclSpec().getStorageClassSpecLoc())) {
// In C++11, the 'register' storage class specifier is deprecated.
// Suppress the warning in system macros, it's used in macros in some
// popular C system headers, such as in glibc's htonl() macro.
Diag(D.getDeclSpec().getStorageClassSpecLoc(),
getLangOpts().CPlusPlus1z ? diag::ext_register_storage_class
: diag::warn_deprecated_register)
<< FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
}
IdentifierInfo *II = Name.getAsIdentifierInfo();
if (!II) {
Diag(D.getIdentifierLoc(), diag::err_bad_variable_name)
<< Name;
return nullptr;
}
DiagnoseFunctionSpecifiers(D.getDeclSpec());
if (!DC->isRecord() && S->getFnParent() == nullptr) {
// C99 6.9p2: The storage-class specifiers auto and register shall not
// appear in the declaration specifiers in an external declaration.
// Global Register+Asm is a GNU extension we support.
if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
D.setInvalidType();
}
}
if (getLangOpts().OpenCL) {
// OpenCL v1.2 s6.9.b p4:
// The sampler type cannot be used with the __local and __global address
// space qualifiers.
if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local ||
R.getAddressSpace() == LangAS::opencl_global)) {
Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
}
// OpenCL 1.2 spec, p6.9 r:
// The event type cannot be used to declare a program scope variable.
// The event type cannot be used with the __local, __constant and __global
// address space qualifiers.
if (R->isEventT()) {
if (S->getParent() == nullptr) {
Diag(D.getLocStart(), diag::err_event_t_global_var);
D.setInvalidType();
}
if (R.getAddressSpace()) {
Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
D.setInvalidType();
}
}
}
bool IsExplicitSpecialization = false;
bool IsVariableTemplateSpecialization = false;
bool IsPartialSpecialization = false;
bool IsVariableTemplate = false;
VarDecl *NewVD = nullptr;
VarTemplateDecl *NewTemplate = nullptr;
TemplateParameterList *TemplateParams = nullptr;
if (!getLangOpts().CPlusPlus) {
NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
D.getIdentifierLoc(), II,
R, TInfo, SC);
if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
ParsingInitForAutoVars.insert(NewVD);
if (D.isInvalidType())
NewVD->setInvalidDecl();
} else {
bool Invalid = false;
if (DC->isRecord() && !CurContext->isRecord()) {
// This is an out-of-line definition of a static data member.
switch (SC) {
case SC_None:
break;
case SC_Static:
Diag(D.getDeclSpec().getStorageClassSpecLoc(),
diag::err_static_out_of_line)
<< FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
break;
case SC_Auto:
case SC_Register:
case SC_Extern:
// [dcl.stc] p2: The auto or register specifiers shall be applied only
// to names of variables declared in a block or to function parameters.
// [dcl.stc] p6: The extern specifier cannot be used in the declaration
// of class members
Diag(D.getDeclSpec().getStorageClassSpecLoc(),
diag::err_storage_class_for_static_member)
<< FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
break;
case SC_PrivateExtern:
llvm_unreachable("C storage class in c++!");
}
}
if (SC == SC_Static && CurContext->isRecord()) {
if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
if (RD->isLocalClass())
Diag(D.getIdentifierLoc(),
diag::err_static_data_member_not_allowed_in_local_class)
<< Name << RD->getDeclName();
// C++98 [class.union]p1: If a union contains a static data member,
// the program is ill-formed. C++11 drops this restriction.
if (RD->isUnion())
Diag(D.getIdentifierLoc(),
getLangOpts().CPlusPlus11
? diag::warn_cxx98_compat_static_data_member_in_union
: diag::ext_static_data_member_in_union) << Name;
// We conservatively disallow static data members in anonymous structs.
else if (!RD->getDeclName())
Diag(D.getIdentifierLoc(),
diag::err_static_data_member_not_allowed_in_anon_struct)
<< Name << RD->isUnion();
}
}
// Match up the template parameter lists with the scope specifier, then
// determine whether we have a template or a template specialization.
TemplateParams = MatchTemplateParametersToScopeSpecifier(
D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
D.getCXXScopeSpec(),
D.getName().getKind() == UnqualifiedId::IK_TemplateId
? D.getName().TemplateId
: nullptr,
TemplateParamLists,
/*never a friend*/ false, IsExplicitSpecialization, Invalid);
if (TemplateParams) {
if (!TemplateParams->size() &&
D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
// There is an extraneous 'template<>' for this variable. Complain
// about it, but allow the declaration of the variable.
Diag(TemplateParams->getTemplateLoc(),
diag::err_template_variable_noparams)
<< II
<< SourceRange(TemplateParams->getTemplateLoc(),
TemplateParams->getRAngleLoc());
TemplateParams = nullptr;
} else {
if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
// This is an explicit specialization or a partial specialization.
// FIXME: Check that we can declare a specialization here.
IsVariableTemplateSpecialization = true;
IsPartialSpecialization = TemplateParams->size() > 0;
} else { // if (TemplateParams->size() > 0)
// This is a template declaration.
IsVariableTemplate = true;
// Check that we can declare a template here.
if (CheckTemplateDeclScope(S, TemplateParams))
return nullptr;
// Only C++1y supports variable templates (N3651).
Diag(D.getIdentifierLoc(),
getLangOpts().CPlusPlus14
? diag::warn_cxx11_compat_variable_template
: diag::ext_variable_template);
}
}
} else {
assert(
(Invalid || D.getName().getKind() != UnqualifiedId::IK_TemplateId) &&
"should have a 'template<>' for this decl");
}
if (IsVariableTemplateSpecialization) {
SourceLocation TemplateKWLoc =
TemplateParamLists.size() > 0
? TemplateParamLists[0]->getTemplateLoc()
: SourceLocation();
DeclResult Res = ActOnVarTemplateSpecialization(
S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
IsPartialSpecialization);
if (Res.isInvalid())
return nullptr;
NewVD = cast<VarDecl>(Res.get());
AddToScope = false;
} else
NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
D.getIdentifierLoc(), II, R, TInfo, SC);
// If this is supposed to be a variable template, create it as such.
if (IsVariableTemplate) {
NewTemplate =
VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
TemplateParams, NewVD);
NewVD->setDescribedVarTemplate(NewTemplate);
}
// If this decl has an auto type in need of deduction, make a note of the
// Decl so we can diagnose uses of it in its own initializer.
if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
ParsingInitForAutoVars.insert(NewVD);
if (D.isInvalidType() || Invalid) {
NewVD->setInvalidDecl();
if (NewTemplate)
NewTemplate->setInvalidDecl();
}
SetNestedNameSpecifier(NewVD, D);
// If we have any template parameter lists that don't directly belong to
// the variable (matching the scope specifier), store them.
unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
if (TemplateParamLists.size() > VDTemplateParamLists)
NewVD->setTemplateParameterListsInfo(
Context, TemplateParamLists.drop_back(VDTemplateParamLists));
if (D.getDeclSpec().isConstexprSpecified())
NewVD->setConstexpr(true);
if (D.getDeclSpec().isConceptSpecified()) {
NewVD->setConcept(true);
// C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
// be declared with the thread_local, inline, friend, or constexpr
// specifiers, [...]
if (D.getDeclSpec().getThreadStorageClassSpec() == TSCS_thread_local) {
Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
diag::err_concept_decl_invalid_specifiers)
<< 0 << 0;
NewVD->setInvalidDecl(true);
}
if (D.getDeclSpec().isConstexprSpecified()) {
Diag(D.getDeclSpec().getConstexprSpecLoc(),
diag::err_concept_decl_invalid_specifiers)
<< 0 << 3;
NewVD->setInvalidDecl(true);
}
}
}
// Set the lexical context. If the declarator has a C++ scope specifier, the
// lexical context will be different from the semantic context.
NewVD->setLexicalDeclContext(CurContext);
if (NewTemplate)
NewTemplate->setLexicalDeclContext(CurContext);
if (IsLocalExternDecl)
NewVD->setLocalExternDecl();
bool EmitTLSUnsupportedError = false;
if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
// C++11 [dcl.stc]p4:
// When thread_local is applied to a variable of block scope the
// storage-class-specifier static is implied if it does not appear
// explicitly.
// Core issue: 'static' is not implied if the variable is declared
// 'extern'.
if (NewVD->hasLocalStorage() &&
(SCSpec != DeclSpec::SCS_unspecified ||
TSCS != DeclSpec::TSCS_thread_local ||
!DC->isFunctionOrMethod()))
Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
diag::err_thread_non_global)
<< DeclSpec::getSpecifierName(TSCS);
else if (!Context.getTargetInfo().isTLSSupported()) {
if (getLangOpts().CUDA) {
// Postpone error emission until we've collected attributes required to
// figure out whether it's a host or device variable and whether the
// error should be ignored.
EmitTLSUnsupportedError = true;
// We still need to mark the variable as TLS so it shows up in AST with
// proper storage class for other tools to use even if we're not going
// to emit any code for it.
NewVD->setTSCSpec(TSCS);
} else
Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
diag::err_thread_unsupported);
} else
NewVD->setTSCSpec(TSCS);
}
// C99 6.7.4p3
// An inline definition of a function with external linkage shall
// not contain a definition of a modifiable object with static or
// thread storage duration...
// We only apply this when the function is required to be defined
// elsewhere, i.e. when the function is not 'extern inline'. Note
// that a local variable with thread storage duration still has to
// be marked 'static'. Also note that it's possible to get these
// semantics in C++ using __attribute__((gnu_inline)).
if (SC == SC_Static && S->getFnParent() != nullptr &&
!NewVD->getType().isConstQualified()) {
FunctionDecl *CurFD = getCurFunctionDecl();
if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
Diag(D.getDeclSpec().getStorageClassSpecLoc(),
diag::warn_static_local_in_extern_inline);
MaybeSuggestAddingStaticToDecl(CurFD);
}
}
if (D.getDeclSpec().isModulePrivateSpecified()) {
if (IsVariableTemplateSpecialization)
Diag(NewVD->getLocation(), diag::err_module_private_specialization)
<< (IsPartialSpecialization ? 1 : 0)
<< FixItHint::CreateRemoval(
D.getDeclSpec().getModulePrivateSpecLoc());
else if (IsExplicitSpecialization)
Diag(NewVD->getLocation(), diag::err_module_private_specialization)
<< 2
<< FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
else if (NewVD->hasLocalStorage())
Diag(NewVD->getLocation(), diag::err_module_private_local)
<< 0 << NewVD->getDeclName()
<< SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
<< FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
else {
NewVD->setModulePrivate();
if (NewTemplate)
NewTemplate->setModulePrivate();
}
}
// Handle attributes prior to checking for duplicates in MergeVarDecl
ProcessDeclAttributes(S, NewVD, D);
if (getLangOpts().CUDA) {
if (EmitTLSUnsupportedError && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD))
Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
diag::err_thread_unsupported);
// CUDA B.2.5: "__shared__ and __constant__ variables have implied static
// storage [duration]."
if (SC == SC_None && S->getFnParent() != nullptr &&
(NewVD->hasAttr<CUDASharedAttr>() ||
NewVD->hasAttr<CUDAConstantAttr>())) {
NewVD->setStorageClass(SC_Static);
}
}
// Ensure that dllimport globals without explicit storage class are treated as
// extern. The storage class is set above using parsed attributes. Now we can
// check the VarDecl itself.
assert(!NewVD->hasAttr<DLLImportAttr>() ||
NewVD->getAttr<DLLImportAttr>()->isInherited() ||
NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
// In auto-retain/release, infer strong retension for variables of
// retainable type.
if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
NewVD->setInvalidDecl();
// Handle GNU asm-label extension (encoded as an attribute).
if (Expr *E = (Expr*)D.getAsmLabel()) {
// The parser guarantees this is a string.
StringLiteral *SE = cast<StringLiteral>(E);
StringRef Label = SE->getString();
if (S->getFnParent() != nullptr) {
switch (SC) {
case SC_None:
case SC_Auto:
Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
break;
case SC_Register:
// Local Named register
if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
break;
case SC_Static:
case SC_Extern:
case SC_PrivateExtern:
break;
}
} else if (SC == SC_Register) {
// Global Named register
if (DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) {
const auto &TI = Context.getTargetInfo();
bool HasSizeMismatch;
if (!TI.isValidGCCRegisterName(Label))
Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
else if (!TI.validateGlobalRegisterVariable(Label,
Context.getTypeSize(R),
HasSizeMismatch))
Diag(E->getExprLoc(), diag::err_asm_invalid_global_var_reg) << Label;
else if (HasSizeMismatch)
Diag(E->getExprLoc(), diag::err_asm_register_size_mismatch) << Label;
}
if (!R->isIntegralType(Context) && !R->isPointerType()) {
Diag(D.getLocStart(), diag::err_asm_bad_register_type);
NewVD->setInvalidDecl(true);
}
}
NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
Context, Label, 0));
} else if (!ExtnameUndeclaredIdentifiers.empty()) {
llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
if (I != ExtnameUndeclaredIdentifiers.end()) {
if (isDeclExternC(NewVD)) {
NewVD->addAttr(I->second);
ExtnameUndeclaredIdentifiers.erase(I);
} else
Diag(NewVD->getLocation(), diag::warn_redefine_extname_not_applied)
<< /*Variable*/1 << NewVD;
}
}
// Diagnose shadowed variables before filtering for scope.
if (D.getCXXScopeSpec().isEmpty())
CheckShadow(S, NewVD, Previous);
// Don't consider existing declarations that are in a different
// scope and are out-of-semantic-context declarations (if the new
// declaration has linkage).
FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
D.getCXXScopeSpec().isNotEmpty() ||
IsExplicitSpecialization ||
IsVariableTemplateSpecialization);
// Check whether the previous declaration is in the same block scope. This
// affects whether we merge types with it, per C++11 [dcl.array]p3.
if (getLangOpts().CPlusPlus &&
NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
NewVD->setPreviousDeclInSameBlockScope(
Previous.isSingleResult() && !Previous.isShadowed() &&
isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
if (!getLangOpts().CPlusPlus) {
D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
} else {
// If this is an explicit specialization of a static data member, check it.
if (IsExplicitSpecialization && !NewVD->isInvalidDecl() &&
CheckMemberSpecialization(NewVD, Previous))
NewVD->setInvalidDecl();
// Merge the decl with the existing one if appropriate.
if (!Previous.empty()) {
if (Previous.isSingleResult() &&
isa<FieldDecl>(Previous.getFoundDecl()) &&
D.getCXXScopeSpec().isSet()) {
// The user tried to define a non-static data member
// out-of-line (C++ [dcl.meaning]p1).
Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
<< D.getCXXScopeSpec().getRange();
Previous.clear();
NewVD->setInvalidDecl();
}
} else if (D.getCXXScopeSpec().isSet()) {
// No previous declaration in the qualifying scope.
Diag(D.getIdentifierLoc(), diag::err_no_member)
<< Name << computeDeclContext(D.getCXXScopeSpec(), true)
<< D.getCXXScopeSpec().getRange();
NewVD->setInvalidDecl();
}
if (!IsVariableTemplateSpecialization)
D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
if (NewTemplate) {
VarTemplateDecl *PrevVarTemplate =
NewVD->getPreviousDecl()
? NewVD->getPreviousDecl()->getDescribedVarTemplate()
: nullptr;
// Check the template parameter list of this declaration, possibly
// merging in the template parameter list from the previous variable
// template declaration.
if (CheckTemplateParameterList(
TemplateParams,
PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
: nullptr,
(D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
DC->isDependentContext())
? TPC_ClassTemplateMember
: TPC_VarTemplate))
NewVD->setInvalidDecl();
// If we are providing an explicit specialization of a static variable
// template, make a note of that.
if (PrevVarTemplate &&
PrevVarTemplate->getInstantiatedFromMemberTemplate())
PrevVarTemplate->setMemberSpecialization();
}
}
ProcessPragmaWeak(S, NewVD);
// If this is the first declaration of an extern C variable, update
// the map of such variables.
if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
isIncompleteDeclExternC(*this, NewVD))
RegisterLocallyScopedExternCDecl(NewVD, S);
if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
Decl *ManglingContextDecl;
if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
NewVD->getDeclContext(), ManglingContextDecl)) {
Context.setManglingNumber(
NewVD, MCtx->getManglingNumber(
NewVD, getMSManglingNumber(getLangOpts(), S)));
Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
}
}
// Special handling of variable named 'main'.
if (Name.isIdentifier() && Name.getAsIdentifierInfo()->isStr("main") &&
NewVD->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
!getLangOpts().Freestanding && !NewVD->getDescribedVarTemplate()) {
// C++ [basic.start.main]p3
// A program that declares a variable main at global scope is ill-formed.
if (getLangOpts().CPlusPlus)
Diag(D.getLocStart(), diag::err_main_global_variable);
// In C, and external-linkage variable named main results in undefined
// behavior.
else if (NewVD->hasExternalFormalLinkage())
Diag(D.getLocStart(), diag::warn_main_redefined);
}
if (D.isRedeclaration() && !Previous.empty()) {
checkDLLAttributeRedeclaration(
*this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewVD,
IsExplicitSpecialization);
}
if (NewTemplate) {
if (NewVD->isInvalidDecl())
NewTemplate->setInvalidDecl();
ActOnDocumentableDecl(NewTemplate);
return NewTemplate;
}
return NewVD;
}
/// \brief Diagnose variable or built-in function shadowing. Implements
/// -Wshadow.
///
/// This method is called whenever a VarDecl is added to a "useful"
/// scope.
///
/// \param S the scope in which the shadowing name is being declared
/// \param R the lookup of the name
///
void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) {
// Return if warning is ignored.
if (Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc()))
return;
// Don't diagnose declarations at file scope.
if (D->hasGlobalStorage())
return;
DeclContext *NewDC = D->getDeclContext();
// Only diagnose if we're shadowing an unambiguous field or variable.
if (R.getResultKind() != LookupResult::Found)
return;
NamedDecl* ShadowedDecl = R.getFoundDecl();
if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl))
return;
// Fields are not shadowed by variables in C++ static methods.
if (isa<FieldDecl>(ShadowedDecl))
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
if (MD->isStatic())
return;
if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
if (shadowedVar->isExternC()) {
// For shadowing external vars, make sure that we point to the global
// declaration, not a locally scoped extern declaration.
for (auto I : shadowedVar->redecls())
if (I->isFileVarDecl()) {
ShadowedDecl = I;
break;
}
}
DeclContext *OldDC = ShadowedDecl->getDeclContext();
// Only warn about certain kinds of shadowing for class members.
if (NewDC && NewDC->isRecord()) {
// In particular, don't warn about shadowing non-class members.
if (!OldDC->isRecord())
return;
// TODO: should we warn about static data members shadowing
// static data members from base classes?
// TODO: don't diagnose for inaccessible shadowed members.
// This is hard to do perfectly because we might friend the
// shadowing context, but that's just a false negative.
}
// Determine what kind of declaration we're shadowing.
unsigned Kind;
if (isa<RecordDecl>(OldDC)) {
if (isa<FieldDecl>(ShadowedDecl))
Kind = 3; // field
else
Kind = 2; // static data member
} else if (OldDC->isFileContext())
Kind = 1; // global
else
Kind = 0; // local
DeclarationName Name = R.getLookupName();
// Emit warning and note.
if (getSourceManager().isInSystemMacro(R.getNameLoc()))
return;
Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC;
Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
}
/// \brief Check -Wshadow without the advantage of a previous lookup.
void Sema::CheckShadow(Scope *S, VarDecl *D) {
if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
return;
LookupResult R(*this, D->getDeclName(), D->getLocation(),
Sema::LookupOrdinaryName, Sema::ForRedeclaration);
LookupName(R, S);
CheckShadow(S, D, R);
}
/// Check for conflict between this global or extern "C" declaration and
/// previous global or extern "C" declarations. This is only used in C++.
template<typename T>
static bool checkGlobalOrExternCConflict(
Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
// The common case: this global doesn't conflict with any extern "C"
// declaration.
return false;
}
if (Prev) {
if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
// Both the old and new declarations have C language linkage. This is a
// redeclaration.
Previous.clear();
Previous.addDecl(Prev);
return true;
}
// This is a global, non-extern "C" declaration, and there is a previous
// non-global extern "C" declaration. Diagnose if this is a variable
// declaration.
if (!isa<VarDecl>(ND))
return false;
} else {
// The declaration is extern "C". Check for any declaration in the
// translation unit which might conflict.
if (IsGlobal) {
// We have already performed the lookup into the translation unit.
IsGlobal = false;
for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
I != E; ++I) {
if (isa<VarDecl>(*I)) {
Prev = *I;
break;
}
}
} else {
DeclContext::lookup_result R =
S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
I != E; ++I) {
if (isa<VarDecl>(*I)) {
Prev = *I;
break;
}
// FIXME: If we have any other entity with this name in global scope,
// the declaration is ill-formed, but that is a defect: it breaks the
// 'stat' hack, for instance. Only variables can have mangled name
// clashes with extern "C" declarations, so only they deserve a
// diagnostic.
}
}
if (!Prev)
return false;
}
// Use the first declaration's location to ensure we point at something which
// is lexically inside an extern "C" linkage-spec.
assert(Prev && "should have found a previous declaration to diagnose");
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
Prev = FD->getFirstDecl();
else
Prev = cast<VarDecl>(Prev)->getFirstDecl();
S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
<< IsGlobal << ND;
S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
<< IsGlobal;
return false;
}
/// Apply special rules for handling extern "C" declarations. Returns \c true
/// if we have found that this is a redeclaration of some prior entity.
///
/// Per C++ [dcl.link]p6:
/// Two declarations [for a function or variable] with C language linkage
/// with the same name that appear in different scopes refer to the same
/// [entity]. An entity with C language linkage shall not be declared with
/// the same name as an entity in global scope.
template<typename T>
static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
LookupResult &Previous) {
if (!S.getLangOpts().CPlusPlus) {
// In C, when declaring a global variable, look for a corresponding 'extern'
// variable declared in function scope. We don't need this in C++, because
// we find local extern decls in the surrounding file-scope DeclContext.
if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
Previous.clear();
Previous.addDecl(Prev);
return true;
}
}
return false;
}
// A declaration in the translation unit can conflict with an extern "C"
// declaration.
if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
// An extern "C" declaration can conflict with a declaration in the
// translation unit or can be a redeclaration of an extern "C" declaration
// in another scope.
if (isIncompleteDeclExternC(S,ND))
return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
// Neither global nor extern "C": nothing to do.
return false;
}
void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
// If the decl is already known invalid, don't check it.
if (NewVD->isInvalidDecl())
return;
TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo();
QualType T = TInfo->getType();
// Defer checking an 'auto' type until its initializer is attached.
if (T->isUndeducedType())
return;
if (NewVD->hasAttrs())
CheckAlignasUnderalignment(NewVD);
if (T->isObjCObjectType()) {
Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
<< FixItHint::CreateInsertion(NewVD->getLocation(), "*");
T = Context.getObjCObjectPointerType(T);
NewVD->setType(T);
}
// Emit an error if an address space was applied to decl with local storage.
// This includes arrays of objects with address space qualifiers, but not
// automatic variables that point to other address spaces.
// ISO/IEC TR 18037 S5.1.2
if (!getLangOpts().OpenCL
&& NewVD->hasLocalStorage() && T.getAddressSpace() != 0) {
Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl);
NewVD->setInvalidDecl();
return;
}
// OpenCL v1.2 s6.8 -- The static qualifier is valid only in program
// scope.
if (getLangOpts().OpenCLVersion == 120 &&
!getOpenCLOptions().cl_clang_storage_class_specifiers &&
NewVD->isStaticLocal()) {
Diag(NewVD->getLocation(), diag::err_static_function_scope);
NewVD->setInvalidDecl();
return;
}
// OpenCL v1.2 s6.5 - All program scope variables must be declared in the
// __constant address space.
// OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
// variables inside a function can also be declared in the global
// address space.
if (getLangOpts().OpenCL) {
if (NewVD->isFileVarDecl()) {
if (!T->isSamplerT() &&
!(T.getAddressSpace() == LangAS::opencl_constant ||
(T.getAddressSpace() == LangAS::opencl_global &&
getLangOpts().OpenCLVersion == 200))) {
if (getLangOpts().OpenCLVersion == 200)
Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
<< "global or constant";
else
Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
<< "constant";
NewVD->setInvalidDecl();
return;
}
} else {
// OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
// variables inside a function can also be declared in the global
// address space.
if (NewVD->isStaticLocal() &&
!(T.getAddressSpace() == LangAS::opencl_constant ||
(T.getAddressSpace() == LangAS::opencl_global &&
getLangOpts().OpenCLVersion == 200))) {
if (getLangOpts().OpenCLVersion == 200)
Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
<< "global or constant";
else
Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
<< "constant";
NewVD->setInvalidDecl();
return;
}
// OpenCL v1.1 s6.5.2 and s6.5.3 no local or constant variables
// in functions.
if (T.getAddressSpace() == LangAS::opencl_constant ||
T.getAddressSpace() == LangAS::opencl_local) {
FunctionDecl *FD = getCurFunctionDecl();
if (FD && !FD->hasAttr<OpenCLKernelAttr>()) {
if (T.getAddressSpace() == LangAS::opencl_constant)
Diag(NewVD->getLocation(), diag::err_opencl_non_kernel_variable)
<< "constant";
else
Diag(NewVD->getLocation(), diag::err_opencl_non_kernel_variable)
<< "local";
NewVD->setInvalidDecl();
return;
}
}
}
}
if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
&& !NewVD->hasAttr<BlocksAttr>()) {
if (getLangOpts().getGC() != LangOptions::NonGC)
Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
else {
assert(!getLangOpts().ObjCAutoRefCount);
Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
}
}
bool isVM = T->isVariablyModifiedType();
if (isVM || NewVD->hasAttr<CleanupAttr>() ||
NewVD->hasAttr<BlocksAttr>())
getCurFunction()->setHasBranchProtectedScope();
if ((isVM && NewVD->hasLinkage()) ||
(T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
bool SizeIsNegative;
llvm::APSInt Oversized;
TypeSourceInfo *FixedTInfo =
TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
SizeIsNegative, Oversized);
if (!FixedTInfo && T->isVariableArrayType()) {
const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
// FIXME: This won't give the correct result for
// int a[10][n];
SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
if (NewVD->isFileVarDecl())
Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
<< SizeRange;
else if (NewVD->isStaticLocal())
Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
<< SizeRange;
else
Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
<< SizeRange;
NewVD->setInvalidDecl();
return;
}
if (!FixedTInfo) {
if (NewVD->isFileVarDecl())
Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
else
Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
NewVD->setInvalidDecl();
return;
}
Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
NewVD->setType(FixedTInfo->getType());
NewVD->setTypeSourceInfo(FixedTInfo);
}
if (T->isVoidType()) {
// C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
// of objects and functions.
if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
<< T;
NewVD->setInvalidDecl();
return;
}
}
if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
NewVD->setInvalidDecl();
return;
}
if (isVM && NewVD->hasAttr<BlocksAttr>()) {
Diag(NewVD->getLocation(), diag::err_block_on_vm);
NewVD->setInvalidDecl();
return;
}
if (NewVD->isConstexpr() && !T->isDependentType() &&
RequireLiteralType(NewVD->getLocation(), T,
diag::err_constexpr_var_non_literal)) {
NewVD->setInvalidDecl();
return;
}
}
/// \brief Perform semantic checking on a newly-created variable
/// declaration.
///
/// This routine performs all of the type-checking required for a
/// variable declaration once it has been built. It is used both to
/// check variables after they have been parsed and their declarators
/// have been translated into a declaration, and to check variables
/// that have been instantiated from a template.
///
/// Sets NewVD->isInvalidDecl() if an error was encountered.
///
/// Returns true if the variable declaration is a redeclaration.
bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
CheckVariableDeclarationType(NewVD);
// If the decl is already known invalid, don't check it.
if (NewVD->isInvalidDecl())
return false;
// If we did not find anything by this name, look for a non-visible
// extern "C" declaration with the same name.
if (Previous.empty() &&
checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
Previous.setShadowed();
if (!Previous.empty()) {
MergeVarDecl(NewVD, Previous);
return true;
}
return false;
}
namespace {
struct FindOverriddenMethod {
Sema *S;
CXXMethodDecl *Method;
/// Member lookup function that determines whether a given C++
/// method overrides a method in a base class, to be used with
/// CXXRecordDecl::lookupInBases().
bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
RecordDecl *BaseRecord =
Specifier->getType()->getAs<RecordType>()->getDecl();
DeclarationName Name = Method->getDeclName();
// FIXME: Do we care about other names here too?
if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
// We really want to find the base class destructor here.
QualType T = S->Context.getTypeDeclType(BaseRecord);
CanQualType CT = S->Context.getCanonicalType(T);
Name = S->Context.DeclarationNames.getCXXDestructorName(CT);
}
for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
Path.Decls = Path.Decls.slice(1)) {
NamedDecl *D = Path.Decls.front();
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
if (MD->isVirtual() && !S->IsOverload(Method, MD, false))
return true;
}
}
return false;
}
};
enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
} // end anonymous namespace
/// \brief Report an error regarding overriding, along with any relevant
/// overriden methods.
///
/// \param DiagID the primary error to report.
/// \param MD the overriding method.
/// \param OEK which overrides to include as notes.
static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
OverrideErrorKind OEK = OEK_All) {
S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
E = MD->end_overridden_methods();
I != E; ++I) {
// This check (& the OEK parameter) could be replaced by a predicate, but
// without lambdas that would be overkill. This is still nicer than writing
// out the diag loop 3 times.
if ((OEK == OEK_All) ||
(OEK == OEK_NonDeleted && !(*I)->isDeleted()) ||
(OEK == OEK_Deleted && (*I)->isDeleted()))
S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
}
}
/// AddOverriddenMethods - See if a method overrides any in the base classes,
/// and if so, check that it's a valid override and remember it.
bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
// Look for methods in base classes that this method might override.
CXXBasePaths Paths;
FindOverriddenMethod FOM;
FOM.Method = MD;
FOM.S = this;
bool hasDeletedOverridenMethods = false;
bool hasNonDeletedOverridenMethods = false;
bool AddedAny = false;
if (DC->lookupInBases(FOM, Paths)) {
for (auto *I : Paths.found_decls()) {
if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
MD->addOverriddenMethod(OldMD->getCanonicalDecl());
if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
!CheckOverridingFunctionAttributes(MD, OldMD) &&
!CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
!CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
hasDeletedOverridenMethods |= OldMD->isDeleted();
hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
AddedAny = true;
}
}
}
}
if (hasDeletedOverridenMethods && !MD->isDeleted()) {
ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
}
if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
}
return AddedAny;
}
namespace {
// Struct for holding all of the extra arguments needed by
// DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
struct ActOnFDArgs {
Scope *S;
Declarator &D;
MultiTemplateParamsArg TemplateParamLists;
bool AddToScope;
};
}
namespace {
// Callback to only accept typo corrections that have a non-zero edit distance.
// Also only accept corrections that have the same parent decl.
class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
public:
DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
CXXRecordDecl *Parent)
: Context(Context), OriginalFD(TypoFD),
ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
bool ValidateCandidate(const TypoCorrection &candidate) override {
if (candidate.getEditDistance() == 0)
return false;
SmallVector<unsigned, 1> MismatchedParams;
for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
CDeclEnd = candidate.end();
CDecl != CDeclEnd; ++CDecl) {
FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
if (FD && !FD->hasBody() &&
hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
CXXRecordDecl *Parent = MD->getParent();
if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
return true;
} else if (!ExpectedParent) {
return true;
}
}
}
return false;
}
private:
ASTContext &Context;
FunctionDecl *OriginalFD;
CXXRecordDecl *ExpectedParent;
};
}
/// \brief Generate diagnostics for an invalid function redeclaration.
///
/// This routine handles generating the diagnostic messages for an invalid
/// function redeclaration, including finding possible similar declarations
/// or performing typo correction if there are no previous declarations with
/// the same name.
///
/// Returns a NamedDecl iff typo correction was performed and substituting in
/// the new declaration name does not cause new errors.
static NamedDecl *DiagnoseInvalidRedeclaration(
Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
DeclarationName Name = NewFD->getDeclName();
DeclContext *NewDC = NewFD->getDeclContext();
SmallVector<unsigned, 1> MismatchedParams;
SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
TypoCorrection Correction;
bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend
: diag::err_member_decl_does_not_match;
LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
IsLocalFriend ? Sema::LookupLocalFriendName
: Sema::LookupOrdinaryName,
Sema::ForRedeclaration);
NewFD->setInvalidDecl();
if (IsLocalFriend)
SemaRef.LookupName(Prev, S);
else
SemaRef.LookupQualifiedName(Prev, NewDC);
assert(!Prev.isAmbiguous() &&
"Cannot have an ambiguity in previous-declaration lookup");
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
if (!Prev.empty()) {
for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
Func != FuncEnd; ++Func) {
FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
if (FD &&
hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
// Add 1 to the index so that 0 can mean the mismatch didn't
// involve a parameter
unsigned ParamNum =
MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
NearMatches.push_back(std::make_pair(FD, ParamNum));
}
}
// If the qualified name lookup yielded nothing, try typo correction
} else if ((Correction = SemaRef.CorrectTypo(
Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
&ExtraArgs.D.getCXXScopeSpec(),
llvm::make_unique<DifferentNameValidatorCCC>(
SemaRef.Context, NewFD, MD ? MD->getParent() : nullptr),
Sema::CTK_ErrorRecovery, IsLocalFriend ? nullptr : NewDC))) {
// Set up everything for the call to ActOnFunctionDeclarator
ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
ExtraArgs.D.getIdentifierLoc());
Previous.clear();
Previous.setLookupName(Correction.getCorrection());
for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
CDeclEnd = Correction.end();
CDecl != CDeclEnd; ++CDecl) {
FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
if (FD && !FD->hasBody() &&
hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
Previous.addDecl(FD);
}
}
bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
NamedDecl *Result;
// Retry building the function declaration with the new previous
// declarations, and with errors suppressed.
{
// Trap errors.
Sema::SFINAETrap Trap(SemaRef);
// TODO: Refactor ActOnFunctionDeclarator so that we can call only the
// pieces need to verify the typo-corrected C++ declaration and hopefully
// eliminate the need for the parameter pack ExtraArgs.
Result = SemaRef.ActOnFunctionDeclarator(
ExtraArgs.S, ExtraArgs.D,
Correction.getCorrectionDecl()->getDeclContext(),
NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
ExtraArgs.AddToScope);
if (Trap.hasErrorOccurred())
Result = nullptr;
}
if (Result) {
// Determine which correction we picked.
Decl *Canonical = Result->getCanonicalDecl();
for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
I != E; ++I)
if ((*I)->getCanonicalDecl() == Canonical)
Correction.setCorrectionDecl(*I);
SemaRef.diagnoseTypo(
Correction,
SemaRef.PDiag(IsLocalFriend
? diag::err_no_matching_local_friend_suggest
: diag::err_member_decl_does_not_match_suggest)
<< Name << NewDC << IsDefinition);
return Result;
}
// Pretend the typo correction never occurred
ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
ExtraArgs.D.getIdentifierLoc());
ExtraArgs.D.setRedeclaration(wasRedeclaration);
Previous.clear();
Previous.setLookupName(Name);
}
SemaRef.Diag(NewFD->getLocation(), DiagMsg)
<< Name << NewDC << IsDefinition << NewFD->getLocation();
bool NewFDisConst = false;
if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
NewFDisConst = NewMD->isConst();
for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
NearMatch != NearMatchEnd; ++NearMatch) {
FunctionDecl *FD = NearMatch->first;
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
bool FDisConst = MD && MD->isConst();
bool IsMember = MD || !IsLocalFriend;
// FIXME: These notes are poorly worded for the local friend case.
if (unsigned Idx = NearMatch->second) {
ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
SourceLocation Loc = FDParam->getTypeSpecStartLoc();
if (Loc.isInvalid()) Loc = FD->getLocation();
SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
: diag::note_local_decl_close_param_match)
<< Idx << FDParam->getType()
<< NewFD->getParamDecl(Idx - 1)->getType();
} else if (FDisConst != NewFDisConst) {
SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
<< NewFDisConst << FD->getSourceRange().getEnd();
} else
SemaRef.Diag(FD->getLocation(),
IsMember ? diag::note_member_def_close_match
: diag::note_local_decl_close_match);
}
return nullptr;
}
static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
switch (D.getDeclSpec().getStorageClassSpec()) {
default: llvm_unreachable("Unknown storage class!");
case DeclSpec::SCS_auto:
case DeclSpec::SCS_register:
case DeclSpec::SCS_mutable:
SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
diag::err_typecheck_sclass_func);
D.setInvalidType();
break;
case DeclSpec::SCS_unspecified: break;
case DeclSpec::SCS_extern:
if (D.getDeclSpec().isExternInLinkageSpec())
return SC_None;
return SC_Extern;
case DeclSpec::SCS_static: {
if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
// C99 6.7.1p5:
// The declaration of an identifier for a function that has
// block scope shall have no explicit storage-class specifier
// other than extern
// See also (C++ [dcl.stc]p4).
SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
diag::err_static_block_func);
break;
} else
return SC_Static;
}
case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
}
// No explicit storage class has already been returned
return SC_None;
}
static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
DeclContext *DC, QualType &R,
TypeSourceInfo *TInfo,
StorageClass SC,
bool &IsVirtualOkay) {
DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
DeclarationName Name = NameInfo.getName();
FunctionDecl *NewFD = nullptr;
bool isInline = D.getDeclSpec().isInlineSpecified();
if (!SemaRef.getLangOpts().CPlusPlus) {
// Determine whether the function was written with a
// prototype. This true when:
// - there is a prototype in the declarator, or
// - the type R of the function is some kind of typedef or other reference
// to a type name (which eventually refers to a function type).
bool HasPrototype =
(D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
(!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType());
NewFD = FunctionDecl::Create(SemaRef.Context, DC,
D.getLocStart(), NameInfo, R,
TInfo, SC, isInline,
HasPrototype, false);
if (D.isInvalidType())
NewFD->setInvalidDecl();
return NewFD;
}
bool isExplicit = D.getDeclSpec().isExplicitSpecified();
bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
// Check that the return type is not an abstract class type.
// For record types, this is done by the AbstractClassUsageDiagnoser once
// the class has been completely parsed.
if (!DC->isRecord() &&
SemaRef.RequireNonAbstractType(
D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
D.setInvalidType();
if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
// This is a C++ constructor declaration.
assert(DC->isRecord() &&
"Constructors can only be declared in a member context");
R = SemaRef.CheckConstructorDeclarator(D, R, SC);
return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
D.getLocStart(), NameInfo,
R, TInfo, isExplicit, isInline,
/*isImplicitlyDeclared=*/false,
isConstexpr);
} else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
// This is a C++ destructor declaration.
if (DC->isRecord()) {
R = SemaRef.CheckDestructorDeclarator(D, R, SC);
CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(
SemaRef.Context, Record,
D.getLocStart(),
NameInfo, R, TInfo, isInline,
/*isImplicitlyDeclared=*/false);
// If the class is complete, then we now create the implicit exception
// specification. If the class is incomplete or dependent, we can't do
// it yet.
if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() &&
Record->getDefinition() && !Record->isBeingDefined() &&
R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) {
SemaRef.AdjustDestructorExceptionSpec(Record, NewDD);
}
IsVirtualOkay = true;
return NewDD;
} else {
SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
D.setInvalidType();
// Create a FunctionDecl to satisfy the function definition parsing
// code path.
return FunctionDecl::Create(SemaRef.Context, DC,
D.getLocStart(),
D.getIdentifierLoc(), Name, R, TInfo,
SC, isInline,
/*hasPrototype=*/true, isConstexpr);
}
} else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
if (!DC->isRecord()) {
SemaRef.Diag(D.getIdentifierLoc(),
diag::err_conv_function_not_member);
return nullptr;
}
SemaRef.CheckConversionDeclarator(D, R, SC);
IsVirtualOkay = true;
return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
D.getLocStart(), NameInfo,
R, TInfo, isInline, isExplicit,
isConstexpr, SourceLocation());
} else if (DC->isRecord()) {
// If the name of the function is the same as the name of the record,
// then this must be an invalid constructor that has a return type.
// (The parser checks for a return type and makes the declarator a
// constructor if it has no return type).
if (Name.getAsIdentifierInfo() &&
Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
<< SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
<< SourceRange(D.getIdentifierLoc());
return nullptr;
}
// This is a C++ method declaration.
CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context,
cast<CXXRecordDecl>(DC),
D.getLocStart(), NameInfo, R,
TInfo, SC, isInline,
isConstexpr, SourceLocation());
IsVirtualOkay = !Ret->isStatic();
return Ret;
} else {
bool isFriend =
SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
if (!isFriend && SemaRef.CurContext->isRecord())
return nullptr;
// Determine whether the function was written with a
// prototype. This true when:
// - we're in C++ (where every function has a prototype),
return FunctionDecl::Create(SemaRef.Context, DC,
D.getLocStart(),
NameInfo, R, TInfo, SC, isInline,
true/*HasPrototype*/, isConstexpr);
}
}
enum OpenCLParamType {
ValidKernelParam,
PtrPtrKernelParam,
PtrKernelParam,
PrivatePtrKernelParam,
InvalidKernelParam,
RecordKernelParam
};
static OpenCLParamType getOpenCLKernelParameterType(QualType PT) {
if (PT->isPointerType()) {
QualType PointeeType = PT->getPointeeType();
if (PointeeType->isPointerType())
return PtrPtrKernelParam;
return PointeeType.getAddressSpace() == 0 ? PrivatePtrKernelParam
: PtrKernelParam;
}
// TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can
// be used as builtin types.
if (PT->isImageType())
return PtrKernelParam;
if (PT->isBooleanType())
return InvalidKernelParam;
if (PT->isEventT())
return InvalidKernelParam;
if (PT->isHalfType())
return InvalidKernelParam;
if (PT->isRecordType())
return RecordKernelParam;
return ValidKernelParam;
}
static void checkIsValidOpenCLKernelParameter(
Sema &S,
Declarator &D,
ParmVarDecl *Param,
llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
QualType PT = Param->getType();
// Cache the valid types we encounter to avoid rechecking structs that are
// used again
if (ValidTypes.count(PT.getTypePtr()))
return;
switch (getOpenCLKernelParameterType(PT)) {
case PtrPtrKernelParam:
// OpenCL v1.2 s6.9.a:
// A kernel function argument cannot be declared as a
// pointer to a pointer type.
S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
D.setInvalidType();
return;
case PrivatePtrKernelParam:
// OpenCL v1.2 s6.9.a:
// A kernel function argument cannot be declared as a
// pointer to the private address space.
S.Diag(Param->getLocation(), diag::err_opencl_private_ptr_kernel_param);
D.setInvalidType();
return;
// OpenCL v1.2 s6.9.k:
// Arguments to kernel functions in a program cannot be declared with the
// built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
// uintptr_t or a struct and/or union that contain fields declared to be
// one of these built-in scalar types.
case InvalidKernelParam:
// OpenCL v1.2 s6.8 n:
// A kernel function argument cannot be declared
// of event_t type.
S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
D.setInvalidType();
return;
case PtrKernelParam:
case ValidKernelParam:
ValidTypes.insert(PT.getTypePtr());
return;
case RecordKernelParam:
break;
}
// Track nested structs we will inspect
SmallVector<const Decl *, 4> VisitStack;
// Track where we are in the nested structs. Items will migrate from
// VisitStack to HistoryStack as we do the DFS for bad field.
SmallVector<const FieldDecl *, 4> HistoryStack;
HistoryStack.push_back(nullptr);
const RecordDecl *PD = PT->castAs<RecordType>()->getDecl();
VisitStack.push_back(PD);
assert(VisitStack.back() && "First decl null?");
do {
const Decl *Next = VisitStack.pop_back_val();
if (!Next) {
assert(!HistoryStack.empty());
// Found a marker, we have gone up a level
if (const FieldDecl *Hist = HistoryStack.pop_back_val())
ValidTypes.insert(Hist->getType().getTypePtr());
continue;
}
// Adds everything except the original parameter declaration (which is not a
// field itself) to the history stack.
const RecordDecl *RD;
if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
HistoryStack.push_back(Field);
RD = Field->getType()->castAs<RecordType>()->getDecl();
} else {
RD = cast<RecordDecl>(Next);
}
// Add a null marker so we know when we've gone back up a level
VisitStack.push_back(nullptr);
for (const auto *FD : RD->fields()) {
QualType QT = FD->getType();
if (ValidTypes.count(QT.getTypePtr()))
continue;
OpenCLParamType ParamType = getOpenCLKernelParameterType(QT);
if (ParamType == ValidKernelParam)
continue;
if (ParamType == RecordKernelParam) {
VisitStack.push_back(FD);
continue;
}
// OpenCL v1.2 s6.9.p:
// Arguments to kernel functions that are declared to be a struct or union
// do not allow OpenCL objects to be passed as elements of the struct or
// union.
if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
ParamType == PrivatePtrKernelParam) {
S.Diag(Param->getLocation(),
diag::err_record_with_pointers_kernel_param)
<< PT->isUnionType()
<< PT;
} else {
S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
}
S.Diag(PD->getLocation(), diag::note_within_field_of_type)
<< PD->getDeclName();
// We have an error, now let's go back up through history and show where
// the offending field came from
for (ArrayRef<const FieldDecl *>::const_iterator
I = HistoryStack.begin() + 1,
E = HistoryStack.end();
I != E; ++I) {
const FieldDecl *OuterField = *I;
S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
<< OuterField->getType();
}
S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
<< QT->isPointerType()
<< QT;
D.setInvalidType();
return;
}
} while (!VisitStack.empty());
}
NamedDecl*
Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
TypeSourceInfo *TInfo, LookupResult &Previous,
MultiTemplateParamsArg TemplateParamLists,
bool &AddToScope) {
QualType R = TInfo->getType();
assert(R.getTypePtr()->isFunctionType());
// TODO: consider using NameInfo for diagnostic.
DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
DeclarationName Name = NameInfo.getName();
StorageClass SC = getFunctionStorageClass(*this, D);
if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
diag::err_invalid_thread)
<< DeclSpec::getSpecifierName(TSCS);
if (D.isFirstDeclarationOfMember())
adjustMemberFunctionCC(R, D.isStaticMember(), D.isCtorOrDtor(),
D.getIdentifierLoc());
bool isFriend = false;
FunctionTemplateDecl *FunctionTemplate = nullptr;
bool isExplicitSpecialization = false;
bool isFunctionTemplateSpecialization = false;
bool isDependentClassScopeExplicitSpecialization = false;
bool HasExplicitTemplateArgs = false;
TemplateArgumentListInfo TemplateArgs;
bool isVirtualOkay = false;
DeclContext *OriginalDC = DC;
bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
isVirtualOkay);
if (!NewFD) return nullptr;
if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
NewFD->setTopLevelDeclInObjCContainer();
// Set the lexical context. If this is a function-scope declaration, or has a
// C++ scope specifier, or is the object of a friend declaration, the lexical
// context will be different from the semantic context.
NewFD->setLexicalDeclContext(CurContext);
if (IsLocalExternDecl)
NewFD->setLocalExternDecl();
if (getLangOpts().CPlusPlus) {
bool isInline = D.getDeclSpec().isInlineSpecified();
bool isVirtual = D.getDeclSpec().isVirtualSpecified();
bool isExplicit = D.getDeclSpec().isExplicitSpecified();
bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
bool isConcept = D.getDeclSpec().isConceptSpecified();
isFriend = D.getDeclSpec().isFriendSpecified();
if (isFriend && !isInline && D.isFunctionDefinition()) {
// C++ [class.friend]p5
// A function can be defined in a friend declaration of a
// class . . . . Such a function is implicitly inline.
NewFD->setImplicitlyInline();
}
// If this is a method defined in an __interface, and is not a constructor
// or an overloaded operator, then set the pure flag (isVirtual will already
// return true).
if (const CXXRecordDecl *Parent =
dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
NewFD->setPure(true);
// C++ [class.union]p2
// A union can have member functions, but not virtual functions.
if (isVirtual && Parent->isUnion())
Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_in_union);
}
SetNestedNameSpecifier(NewFD, D);
isExplicitSpecialization = false;
isFunctionTemplateSpecialization = false;
if (D.isInvalidType())
NewFD->setInvalidDecl();
// Match up the template parameter lists with the scope specifier, then
// determine whether we have a template or a template specialization.
bool Invalid = false;
if (TemplateParameterList *TemplateParams =
MatchTemplateParametersToScopeSpecifier(
D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
D.getCXXScopeSpec(),
D.getName().getKind() == UnqualifiedId::IK_TemplateId
? D.getName().TemplateId
: nullptr,
TemplateParamLists, isFriend, isExplicitSpecialization,
Invalid)) {
if (TemplateParams->size() > 0) {
// This is a function template
// Check that we can declare a template here.
if (CheckTemplateDeclScope(S, TemplateParams))
NewFD->setInvalidDecl();
// A destructor cannot be a template.
if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
Diag(NewFD->getLocation(), diag::err_destructor_template);
NewFD->setInvalidDecl();
}
// If we're adding a template to a dependent context, we may need to
// rebuilding some of the types used within the template parameter list,
// now that we know what the current instantiation is.
if (DC->isDependentContext()) {
ContextRAII SavedContext(*this, DC);
if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
Invalid = true;
}
FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
NewFD->getLocation(),
Name, TemplateParams,
NewFD);
FunctionTemplate->setLexicalDeclContext(CurContext);
NewFD->setDescribedFunctionTemplate(FunctionTemplate);
// For source fidelity, store the other template param lists.
if (TemplateParamLists.size() > 1) {
NewFD->setTemplateParameterListsInfo(Context,
TemplateParamLists.drop_back(1));
}
} else {
// This is a function template specialization.
isFunctionTemplateSpecialization = true;
// For source fidelity, store all the template param lists.
if (TemplateParamLists.size() > 0)
NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
// C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
if (isFriend) {
// We want to remove the "template<>", found here.
SourceRange RemoveRange = TemplateParams->getSourceRange();
// If we remove the template<> and the name is not a
// template-id, we're actually silently creating a problem:
// the friend declaration will refer to an untemplated decl,
// and clearly the user wants a template specialization. So
// we need to insert '<>' after the name.
SourceLocation InsertLoc;
if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
InsertLoc = D.getName().getSourceRange().getEnd();
InsertLoc = getLocForEndOfToken(InsertLoc);
}
Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
<< Name << RemoveRange
<< FixItHint::CreateRemoval(RemoveRange)
<< FixItHint::CreateInsertion(InsertLoc, "<>");
}
}
}
else {
// All template param lists were matched against the scope specifier:
// this is NOT (an explicit specialization of) a template.
if (TemplateParamLists.size() > 0)
// For source fidelity, store all the template param lists.
NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
}
if (Invalid) {
NewFD->setInvalidDecl();
if (FunctionTemplate)
FunctionTemplate->setInvalidDecl();
}
// C++ [dcl.fct.spec]p5:
// The virtual specifier shall only be used in declarations of
// nonstatic class member functions that appear within a
// member-specification of a class declaration; see 10.3.
//
if (isVirtual && !NewFD->isInvalidDecl()) {
if (!isVirtualOkay) {
Diag(D.getDeclSpec().getVirtualSpecLoc(),
diag::err_virtual_non_function);
} else if (!CurContext->isRecord()) {
// 'virtual' was specified outside of the class.
Diag(D.getDeclSpec().getVirtualSpecLoc(),
diag::err_virtual_out_of_class)
<< FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
} else if (NewFD->getDescribedFunctionTemplate()) {
// C++ [temp.mem]p3:
// A member function template shall not be virtual.
Diag(D.getDeclSpec().getVirtualSpecLoc(),
diag::err_virtual_member_function_template)
<< FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
} else {
// Okay: Add virtual to the method.
NewFD->setVirtualAsWritten(true);
}
if (getLangOpts().CPlusPlus14 &&
NewFD->getReturnType()->isUndeducedType())
Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
}
if (getLangOpts().CPlusPlus14 &&
(NewFD->isDependentContext() ||
(isFriend && CurContext->isDependentContext())) &&
NewFD->getReturnType()->isUndeducedType()) {
// If the function template is referenced directly (for instance, as a
// member of the current instantiation), pretend it has a dependent type.
// This is not really justified by the standard, but is the only sane
// thing to do.
// FIXME: For a friend function, we have not marked the function as being
// a friend yet, so 'isDependentContext' on the FD doesn't work.
const FunctionProtoType *FPT =
NewFD->getType()->castAs<FunctionProtoType>();
QualType Result =
SubstAutoType(FPT->getReturnType(), Context.DependentTy);
NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
FPT->getExtProtoInfo()));
}
// C++ [dcl.fct.spec]p3:
// The inline specifier shall not appear on a block scope function
// declaration.
if (isInline && !NewFD->isInvalidDecl()) {
if (CurContext->isFunctionOrMethod()) {
// 'inline' is not allowed on block scope function declaration.
Diag(D.getDeclSpec().getInlineSpecLoc(),
diag::err_inline_declaration_block_scope) << Name
<< FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
}
}
// C++ [dcl.fct.spec]p6:
// The explicit specifier shall be used only in the declaration of a
// constructor or conversion function within its class definition;
// see 12.3.1 and 12.3.2.
if (isExplicit && !NewFD->isInvalidDecl()) {
if (!CurContext->isRecord()) {
// 'explicit' was specified outside of the class.
Diag(D.getDeclSpec().getExplicitSpecLoc(),
diag::err_explicit_out_of_class)
<< FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
} else if (!isa<CXXConstructorDecl>(NewFD) &&
!isa<CXXConversionDecl>(NewFD)) {
// 'explicit' was specified on a function that wasn't a constructor
// or conversion function.
Diag(D.getDeclSpec().getExplicitSpecLoc(),
diag::err_explicit_non_ctor_or_conv_function)
<< FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
}
}
if (isConstexpr) {
// C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
// are implicitly inline.
NewFD->setImplicitlyInline();
// C++11 [dcl.constexpr]p3: functions declared constexpr are required to
// be either constructors or to return a literal type. Therefore,
// destructors cannot be declared constexpr.
if (isa<CXXDestructorDecl>(NewFD))
Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor);
}
if (isConcept) {
// C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
// applied only to the definition of a function template [...]
if (!D.isFunctionDefinition()) {
Diag(D.getDeclSpec().getConceptSpecLoc(),
diag::err_function_concept_not_defined);
NewFD->setInvalidDecl();
}
// C++ Concepts TS [dcl.spec.concept]p1: [...] A function concept shall
// have no exception-specification and is treated as if it were specified
// with noexcept(true) (15.4). [...]
if (const FunctionProtoType *FPT = R->getAs<FunctionProtoType>()) {
if (FPT->hasExceptionSpec()) {
SourceRange Range;
if (D.isFunctionDeclarator())
Range = D.getFunctionTypeInfo().getExceptionSpecRange();
Diag(NewFD->getLocation(), diag::err_function_concept_exception_spec)
<< FixItHint::CreateRemoval(Range);
NewFD->setInvalidDecl();
} else {
Context.adjustExceptionSpec(NewFD, EST_BasicNoexcept);
}
// C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
// following restrictions:
// - The declaration's parameter list shall be equivalent to an empty
// parameter list.
if (FPT->getNumParams() > 0 || FPT->isVariadic())
Diag(NewFD->getLocation(), diag::err_function_concept_with_params);
}
// C++ Concepts TS [dcl.spec.concept]p2: Every concept definition is
// implicity defined to be a constexpr declaration (implicitly inline)
NewFD->setImplicitlyInline();
// C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
// be declared with the thread_local, inline, friend, or constexpr
// specifiers, [...]
if (isInline) {
Diag(D.getDeclSpec().getInlineSpecLoc(),
diag::err_concept_decl_invalid_specifiers)
<< 1 << 1;
NewFD->setInvalidDecl(true);
}
if (isFriend) {
Diag(D.getDeclSpec().getFriendSpecLoc(),
diag::err_concept_decl_invalid_specifiers)
<< 1 << 2;
NewFD->setInvalidDecl(true);
}
if (isConstexpr) {
Diag(D.getDeclSpec().getConstexprSpecLoc(),
diag::err_concept_decl_invalid_specifiers)
<< 1 << 3;
NewFD->setInvalidDecl(true);
}
}
// If __module_private__ was specified, mark the function accordingly.
if (D.getDeclSpec().isModulePrivateSpecified()) {
if (isFunctionTemplateSpecialization) {
SourceLocation ModulePrivateLoc
= D.getDeclSpec().getModulePrivateSpecLoc();
Diag(ModulePrivateLoc, diag::err_module_private_specialization)
<< 0
<< FixItHint::CreateRemoval(ModulePrivateLoc);
} else {
NewFD->setModulePrivate();
if (FunctionTemplate)
FunctionTemplate->setModulePrivate();
}
}
if (isFriend) {
if (FunctionTemplate) {
FunctionTemplate->setObjectOfFriendDecl();
FunctionTemplate->setAccess(AS_public);
}
NewFD->setObjectOfFriendDecl();
NewFD->setAccess(AS_public);
}
// If a function is defined as defaulted or deleted, mark it as such now.
// FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
// definition kind to FDK_Definition.
switch (D.getFunctionDefinitionKind()) {
case FDK_Declaration:
case FDK_Definition:
break;
case FDK_Defaulted:
NewFD->setDefaulted();
break;
case FDK_Deleted:
NewFD->setDeletedAsWritten();
break;
}
if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
D.isFunctionDefinition()) {
// C++ [class.mfct]p2:
// A member function may be defined (8.4) in its class definition, in
// which case it is an inline member function (7.1.2)
NewFD->setImplicitlyInline();
}
if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
!CurContext->isRecord()) {
// C++ [class.static]p1:
// A data or function member of a class may be declared static
// in a class definition, in which case it is a static member of
// the class.
// Complain about the 'static' specifier if it's on an out-of-line
// member function definition.
Diag(D.getDeclSpec().getStorageClassSpecLoc(),
diag::err_static_out_of_line)
<< FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
}
// C++11 [except.spec]p15:
// A deallocation function with no exception-specification is treated
// as if it were specified with noexcept(true).
const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
if ((Name.getCXXOverloadedOperator() == OO_Delete ||
Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
NewFD->setType(Context.getFunctionType(
FPT->getReturnType(), FPT->getParamTypes(),
FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
}
// Filter out previous declarations that don't match the scope.
FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
D.getCXXScopeSpec().isNotEmpty() ||
isExplicitSpecialization ||
isFunctionTemplateSpecialization);
// Handle GNU asm-label extension (encoded as an attribute).
if (Expr *E = (Expr*) D.getAsmLabel()) {
// The parser guarantees this is a string.
StringLiteral *SE = cast<StringLiteral>(E);
NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
SE->getString(), 0));
} else if (!ExtnameUndeclaredIdentifiers.empty()) {
llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
if (I != ExtnameUndeclaredIdentifiers.end()) {
if (isDeclExternC(NewFD)) {
NewFD->addAttr(I->second);
ExtnameUndeclaredIdentifiers.erase(I);
} else
Diag(NewFD->getLocation(), diag::warn_redefine_extname_not_applied)
<< /*Variable*/0 << NewFD;
}
}
// Copy the parameter declarations from the declarator D to the function
// declaration NewFD, if they are available. First scavenge them into Params.
SmallVector<ParmVarDecl*, 16> Params;
if (D.isFunctionDeclarator()) {
DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
// Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
// function that takes no arguments, not a function that takes a
// single void argument.
// We let through "const void" here because Sema::GetTypeForDeclarator
// already checks for that case.
if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
assert(Param->getDeclContext() != NewFD && "Was set before ?");
Param->setDeclContext(NewFD);
Params.push_back(Param);
if (Param->isInvalidDecl())
NewFD->setInvalidDecl();
}
}
} else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
// When we're declaring a function with a typedef, typeof, etc as in the
// following example, we'll need to synthesize (unnamed)
// parameters for use in the declaration.
//
// @code
// typedef void fn(int);
// fn f;
// @endcode
// Synthesize a parameter for each argument type.
for (const auto &AI : FT->param_types()) {
ParmVarDecl *Param =
BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
Param->setScopeInfo(0, Params.size());
Params.push_back(Param);
}
} else {
assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
"Should not need args for typedef of non-prototype fn");
}
// Finally, we know we have the right number of parameters, install them.
NewFD->setParams(Params);
// Find all anonymous symbols defined during the declaration of this function
// and add to NewFD. This lets us track decls such 'enum Y' in:
//
// void f(enum Y {AA} x) {}
//
// which would otherwise incorrectly end up in the translation unit scope.
NewFD->setDeclsInPrototypeScope(DeclsInPrototypeScope);
DeclsInPrototypeScope.clear();
if (D.getDeclSpec().isNoreturnSpecified())
NewFD->addAttr(
::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
Context, 0));
// Functions returning a variably modified type violate C99 6.7.5.2p2
// because all functions have linkage.
if (!NewFD->isInvalidDecl() &&
NewFD->getReturnType()->isVariablyModifiedType()) {
Diag(NewFD->getLocation(), diag::err_vm_func_decl);
NewFD->setInvalidDecl();
}
// Apply an implicit SectionAttr if #pragma code_seg is active.
if (CodeSegStack.CurrentValue && D.isFunctionDefinition() &&
!NewFD->hasAttr<SectionAttr>()) {
NewFD->addAttr(
SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
CodeSegStack.CurrentValue->getString(),
CodeSegStack.CurrentPragmaLocation));
if (UnifySection(CodeSegStack.CurrentValue->getString(),
ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
ASTContext::PSF_Read,
NewFD))
NewFD->dropAttr<SectionAttr>();
}
// Handle attributes.
ProcessDeclAttributes(S, NewFD, D);
if (getLangOpts().OpenCL) {
// OpenCL v1.1 s6.5: Using an address space qualifier in a function return
// type declaration will generate a compilation error.
unsigned AddressSpace = NewFD->getReturnType().getAddressSpace();
if (AddressSpace == LangAS::opencl_local ||
AddressSpace == LangAS::opencl_global ||
AddressSpace == LangAS::opencl_constant) {
Diag(NewFD->getLocation(),
diag::err_opencl_return_value_with_address_space);
NewFD->setInvalidDecl();
}
}
if (!getLangOpts().CPlusPlus) {
// Perform semantic checking on the function declaration.
bool isExplicitSpecialization=false;
if (!NewFD->isInvalidDecl() && NewFD->isMain())
CheckMain(NewFD, D.getDeclSpec());
if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
CheckMSVCRTEntryPoint(NewFD);
if (!NewFD->isInvalidDecl())
D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
isExplicitSpecialization));
else if (!Previous.empty())
// Recover gracefully from an invalid redeclaration.
D.setRedeclaration(true);
assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
Previous.getResultKind() != LookupResult::FoundOverloaded) &&
"previous declaration set still overloaded");
// Diagnose no-prototype function declarations with calling conventions that
// don't support variadic calls. Only do this in C and do it after merging
// possibly prototyped redeclarations.
const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
CallingConv CC = FT->getExtInfo().getCC();
if (!supportsVariadicCall(CC)) {
// Windows system headers sometimes accidentally use stdcall without
// (void) parameters, so we relax this to a warning.
int DiagID =
CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
Diag(NewFD->getLocation(), DiagID)
<< FunctionType::getNameForCallConv(CC);
}
}
} else {
// C++11 [replacement.functions]p3:
// The program's definitions shall not be specified as inline.
//
// N.B. We diagnose declarations instead of definitions per LWG issue 2340.
//
// Suppress the diagnostic if the function is __attribute__((used)), since
// that forces an external definition to be emitted.
if (D.getDeclSpec().isInlineSpecified() &&
NewFD->isReplaceableGlobalAllocationFunction() &&
!NewFD->hasAttr<UsedAttr>())
Diag(D.getDeclSpec().getInlineSpecLoc(),
diag::ext_operator_new_delete_declared_inline)
<< NewFD->getDeclName();
// If the declarator is a template-id, translate the parser's template
// argument list into our AST format.
if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
TemplateId->NumArgs);
translateTemplateArguments(TemplateArgsPtr,
TemplateArgs);
HasExplicitTemplateArgs = true;
if (NewFD->isInvalidDecl()) {
HasExplicitTemplateArgs = false;
} else if (FunctionTemplate) {
// Function template with explicit template arguments.
Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
<< SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
HasExplicitTemplateArgs = false;
} else {
assert((isFunctionTemplateSpecialization ||
D.getDeclSpec().isFriendSpecified()) &&
"should have a 'template<>' for this decl");
// "friend void foo<>(int);" is an implicit specialization decl.
isFunctionTemplateSpecialization = true;
}
} else if (isFriend && isFunctionTemplateSpecialization) {
// This combination is only possible in a recovery case; the user
// wrote something like:
// template <> friend void foo(int);
// which we're recovering from as if the user had written:
// friend void foo<>(int);
// Go ahead and fake up a template id.
HasExplicitTemplateArgs = true;
TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
}
// If it's a friend (and only if it's a friend), it's possible
// that either the specialized function type or the specialized
// template is dependent, and therefore matching will fail. In
// this case, don't check the specialization yet.
bool InstantiationDependent = false;
if (isFunctionTemplateSpecialization && isFriend &&
(NewFD->getType()->isDependentType() || DC->isDependentContext() ||
TemplateSpecializationType::anyDependentTemplateArguments(
TemplateArgs.getArgumentArray(), TemplateArgs.size(),
InstantiationDependent))) {
assert(HasExplicitTemplateArgs &&
"friend function specialization without template args");
if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
Previous))
NewFD->setInvalidDecl();
} else if (isFunctionTemplateSpecialization) {
if (CurContext->isDependentContext() && CurContext->isRecord()
&& !isFriend) {
isDependentClassScopeExplicitSpecialization = true;
Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
diag::ext_function_specialization_in_class :
diag::err_function_specialization_in_class)
<< NewFD->getDeclName();
} else if (CheckFunctionTemplateSpecialization(NewFD,
(HasExplicitTemplateArgs ? &TemplateArgs
: nullptr),
Previous))
NewFD->setInvalidDecl();
// C++ [dcl.stc]p1:
// A storage-class-specifier shall not be specified in an explicit
// specialization (14.7.3)
FunctionTemplateSpecializationInfo *Info =
NewFD->getTemplateSpecializationInfo();
if (Info && SC != SC_None) {
if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
Diag(NewFD->getLocation(),
diag::err_explicit_specialization_inconsistent_storage_class)
<< SC
<< FixItHint::CreateRemoval(
D.getDeclSpec().getStorageClassSpecLoc());
else
Diag(NewFD->getLocation(),
diag::ext_explicit_specialization_storage_class)
<< FixItHint::CreateRemoval(
D.getDeclSpec().getStorageClassSpecLoc());
}
} else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) {
if (CheckMemberSpecialization(NewFD, Previous))
NewFD->setInvalidDecl();
}
// Perform semantic checking on the function declaration.
if (!isDependentClassScopeExplicitSpecialization) {
if (!NewFD->isInvalidDecl() && NewFD->isMain())
CheckMain(NewFD, D.getDeclSpec());
if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
CheckMSVCRTEntryPoint(NewFD);
if (!NewFD->isInvalidDecl())
D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
isExplicitSpecialization));
else if (!Previous.empty())
// Recover gracefully from an invalid redeclaration.
D.setRedeclaration(true);
}
assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
Previous.getResultKind() != LookupResult::FoundOverloaded) &&
"previous declaration set still overloaded");
NamedDecl *PrincipalDecl = (FunctionTemplate
? cast<NamedDecl>(FunctionTemplate)
: NewFD);
if (isFriend && D.isRedeclaration()) {
AccessSpecifier Access = AS_public;
if (!NewFD->isInvalidDecl())
Access = NewFD->getPreviousDecl()->getAccess();
NewFD->setAccess(Access);
if (FunctionTemplate) FunctionTemplate->setAccess(Access);
}
if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
PrincipalDecl->setNonMemberOperator();
// If we have a function template, check the template parameter
// list. This will check and merge default template arguments.
if (FunctionTemplate) {
FunctionTemplateDecl *PrevTemplate =
FunctionTemplate->getPreviousDecl();
CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
PrevTemplate ? PrevTemplate->getTemplateParameters()
: nullptr,
D.getDeclSpec().isFriendSpecified()
? (D.isFunctionDefinition()
? TPC_FriendFunctionTemplateDefinition
: TPC_FriendFunctionTemplate)
: (D.getCXXScopeSpec().isSet() &&
DC && DC->isRecord() &&
DC->isDependentContext())
? TPC_ClassTemplateMember
: TPC_FunctionTemplate);
}
if (NewFD->isInvalidDecl()) {
// Ignore all the rest of this.
} else if (!D.isRedeclaration()) {
struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
AddToScope };
// Fake up an access specifier if it's supposed to be a class member.
if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
NewFD->setAccess(AS_public);
// Qualified decls generally require a previous declaration.
if (D.getCXXScopeSpec().isSet()) {
// ...with the major exception of templated-scope or
// dependent-scope friend declarations.
// TODO: we currently also suppress this check in dependent
// contexts because (1) the parameter depth will be off when
// matching friend templates and (2) we might actually be
// selecting a friend based on a dependent factor. But there
// are situations where these conditions don't apply and we
// can actually do this check immediately.
if (isFriend &&
(TemplateParamLists.size() ||
D.getCXXScopeSpec().getScopeRep()->isDependent() ||
CurContext->isDependentContext())) {
// ignore these
} else {
// The user tried to provide an out-of-line definition for a
// function that is a member of a class or namespace, but there
// was no such member function declared (C++ [class.mfct]p2,
// C++ [namespace.memdef]p2). For example:
//
// class X {
// void f() const;
// };
//
// void X::f() { } // ill-formed
//
// Complain about this problem, and attempt to suggest close
// matches (e.g., those that differ only in cv-qualifiers and
// whether the parameter types are references).
if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
*this, Previous, NewFD, ExtraArgs, false, nullptr)) {
AddToScope = ExtraArgs.AddToScope;
return Result;
}
}
// Unqualified local friend declarations are required to resolve
// to something.
} else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
*this, Previous, NewFD, ExtraArgs, true, S)) {
AddToScope = ExtraArgs.AddToScope;
return Result;
}
}
} else if (!D.isFunctionDefinition() &&
isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
!isFriend && !isFunctionTemplateSpecialization &&
!isExplicitSpecialization) {
// An out-of-line member function declaration must also be a
// definition (C++ [class.mfct]p2).
// Note that this is not the case for explicit specializations of
// function templates or member functions of class templates, per
// C++ [temp.expl.spec]p2. We also allow these declarations as an
// extension for compatibility with old SWIG code which likes to
// generate them.
Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
<< D.getCXXScopeSpec().getRange();
}
}
ProcessPragmaWeak(S, NewFD);
checkAttributesAfterMerging(*this, *NewFD);
AddKnownFunctionAttributes(NewFD);
if (NewFD->hasAttr<OverloadableAttr>() &&
!NewFD->getType()->getAs<FunctionProtoType>()) {
Diag(NewFD->getLocation(),
diag::err_attribute_overloadable_no_prototype)
<< NewFD;
// Turn this into a variadic function with no parameters.
const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
FunctionProtoType::ExtProtoInfo EPI(
Context.getDefaultCallingConvention(true, false));
EPI.Variadic = true;
EPI.ExtInfo = FT->getExtInfo();
QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
NewFD->setType(R);
}
// If there's a #pragma GCC visibility in scope, and this isn't a class
// member, set the visibility of this function.
if (!DC->isRecord() && NewFD->isExternallyVisible())
AddPushedVisibilityAttribute(NewFD);
// If there's a #pragma clang arc_cf_code_audited in scope, consider
// marking the function.
AddCFAuditedAttribute(NewFD);
// If this is a function definition, check if we have to apply optnone due to
// a pragma.
if(D.isFunctionDefinition())
AddRangeBasedOptnone(NewFD);
// If this is the first declaration of an extern C variable, update
// the map of such variables.
if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
isIncompleteDeclExternC(*this, NewFD))
RegisterLocallyScopedExternCDecl(NewFD, S);
// Set this FunctionDecl's range up to the right paren.
NewFD->setRangeEnd(D.getSourceRange().getEnd());
if (D.isRedeclaration() && !Previous.empty()) {
checkDLLAttributeRedeclaration(
*this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewFD,
isExplicitSpecialization || isFunctionTemplateSpecialization);
}
if (getLangOpts().CPlusPlus) {
if (FunctionTemplate) {
if (NewFD->isInvalidDecl())
FunctionTemplate->setInvalidDecl();
return FunctionTemplate;
}
}
if (NewFD->hasAttr<OpenCLKernelAttr>()) {
// OpenCL v1.2 s6.8 static is invalid for kernel functions.
if ((getLangOpts().OpenCLVersion >= 120)
&& (SC == SC_Static)) {
Diag(D.getIdentifierLoc(), diag::err_static_kernel);
D.setInvalidType();
}
// OpenCL v1.2, s6.9 -- Kernels can only have return type void.
if (!NewFD->getReturnType()->isVoidType()) {
SourceRange RTRange = NewFD->getReturnTypeSourceRange();
Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
<< (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
: FixItHint());
D.setInvalidType();
}
llvm::SmallPtrSet<const Type *, 16> ValidTypes;
for (auto Param : NewFD->params())
checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
}
MarkUnusedFileScopedDecl(NewFD);
if (getLangOpts().CUDA)
if (IdentifierInfo *II = NewFD->getIdentifier())
if (!NewFD->isInvalidDecl() &&
NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
if (II->isStr("cudaConfigureCall")) {
if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
Diag(NewFD->getLocation(), diag::err_config_scalar_return);
Context.setcudaConfigureCallDecl(NewFD);
}
}
// Here we have an function template explicit specialization at class scope.
// The actually specialization will be postponed to template instatiation
// time via the ClassScopeFunctionSpecializationDecl node.
if (isDependentClassScopeExplicitSpecialization) {
ClassScopeFunctionSpecializationDecl *NewSpec =
ClassScopeFunctionSpecializationDecl::Create(
Context, CurContext, SourceLocation(),
cast<CXXMethodDecl>(NewFD),
HasExplicitTemplateArgs, TemplateArgs);
CurContext->addDecl(NewSpec);
AddToScope = false;
}
return NewFD;
}
/// \brief Perform semantic checking of a new function declaration.
///
/// Performs semantic analysis of the new function declaration
/// NewFD. This routine performs all semantic checking that does not
/// require the actual declarator involved in the declaration, and is
/// used both for the declaration of functions as they are parsed
/// (called via ActOnDeclarator) and for the declaration of functions
/// that have been instantiated via C++ template instantiation (called
/// via InstantiateDecl).
///
/// \param IsExplicitSpecialization whether this new function declaration is
/// an explicit specialization of the previous declaration.
///
/// This sets NewFD->isInvalidDecl() to true if there was an error.
///
/// \returns true if the function declaration is a redeclaration.
bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
LookupResult &Previous,
bool IsExplicitSpecialization) {
assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
"Variably modified return types are not handled here");
// Determine whether the type of this function should be merged with
// a previous visible declaration. This never happens for functions in C++,
// and always happens in C if the previous declaration was visible.
bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
!Previous.isShadowed();
bool Redeclaration = false;
NamedDecl *OldDecl = nullptr;
// Merge or overload the declaration with an existing declaration of
// the same name, if appropriate.
if (!Previous.empty()) {
// Determine whether NewFD is an overload of PrevDecl or
// a declaration that requires merging. If it's an overload,
// there's no more work to do here; we'll just add the new
// function to the scope.
if (!AllowOverloadingOfFunction(Previous, Context)) {
NamedDecl *Candidate = Previous.getRepresentativeDecl();
if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
Redeclaration = true;
OldDecl = Candidate;
}
} else {
switch (CheckOverload(S, NewFD, Previous, OldDecl,
/*NewIsUsingDecl*/ false)) {
case Ovl_Match:
Redeclaration = true;
break;
case Ovl_NonFunction:
Redeclaration = true;
break;
case Ovl_Overload:
Redeclaration = false;
break;
}
if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
// If a function name is overloadable in C, then every function
// with that name must be marked "overloadable".
Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
<< Redeclaration << NewFD;
NamedDecl *OverloadedDecl = nullptr;
if (Redeclaration)
OverloadedDecl = OldDecl;
else if (!Previous.empty())
OverloadedDecl = Previous.getRepresentativeDecl();
if (OverloadedDecl)
Diag(OverloadedDecl->getLocation(),
diag::note_attribute_overloadable_prev_overload);
NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
}
}
}
// Check for a previous extern "C" declaration with this name.
if (!Redeclaration &&
checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
if (!Previous.empty()) {
// This is an extern "C" declaration with the same name as a previous
// declaration, and thus redeclares that entity...
Redeclaration = true;
OldDecl = Previous.getFoundDecl();
MergeTypeWithPrevious = false;
// ... except in the presence of __attribute__((overloadable)).
if (OldDecl->hasAttr<OverloadableAttr>()) {
if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
<< Redeclaration << NewFD;
Diag(Previous.getFoundDecl()->getLocation(),
diag::note_attribute_overloadable_prev_overload);
NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
}
if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
Redeclaration = false;
OldDecl = nullptr;
}
}
}
}
// C++11 [dcl.constexpr]p8:
// A constexpr specifier for a non-static member function that is not
// a constructor declares that member function to be const.
//
// This needs to be delayed until we know whether this is an out-of-line
// definition of a static member function.
//
// This rule is not present in C++1y, so we produce a backwards
// compatibility warning whenever it happens in C++11.
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
!MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
(MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
CXXMethodDecl *OldMD = nullptr;
if (OldDecl)
OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
if (!OldMD || !OldMD->isStatic()) {
const FunctionProtoType *FPT =
MD->getType()->castAs<FunctionProtoType>();
FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
EPI.TypeQuals |= Qualifiers::Const;
MD->setType(Context.getFunctionType(FPT->getReturnType(),
FPT->getParamTypes(), EPI));
// Warn that we did this, if we're not performing template instantiation.
// In that case, we'll have warned already when the template was defined.
if (ActiveTemplateInstantiations.empty()) {
SourceLocation AddConstLoc;
if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
.IgnoreParens().getAs<FunctionTypeLoc>())
AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
<< FixItHint::CreateInsertion(AddConstLoc, " const");
}
}
}
if (Redeclaration) {
// NewFD and OldDecl represent declarations that need to be
// merged.
if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
NewFD->setInvalidDecl();
return Redeclaration;
}
Previous.clear();
Previous.addDecl(OldDecl);
if (FunctionTemplateDecl *OldTemplateDecl
= dyn_cast<FunctionTemplateDecl>(OldDecl)) {
NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl());
FunctionTemplateDecl *NewTemplateDecl
= NewFD->getDescribedFunctionTemplate();
assert(NewTemplateDecl && "Template/non-template mismatch");
if (CXXMethodDecl *Method
= dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) {
Method->setAccess(OldTemplateDecl->getAccess());
NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
}
// If this is an explicit specialization of a member that is a function
// template, mark it as a member specialization.
if (IsExplicitSpecialization &&
NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
NewTemplateDecl->setMemberSpecialization();
assert(OldTemplateDecl->isMemberSpecialization());
}
} else {
// This needs to happen first so that 'inline' propagates.
NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
if (isa<CXXMethodDecl>(NewFD))
NewFD->setAccess(OldDecl->getAccess());
}
}
// Semantic checking for this function declaration (in isolation).
if (getLangOpts().CPlusPlus) {
// C++-specific checks.
if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
CheckConstructor(Constructor);
} else if (CXXDestructorDecl *Destructor =
dyn_cast<CXXDestructorDecl>(NewFD)) {
CXXRecordDecl *Record = Destructor->getParent();
QualType ClassType = Context.getTypeDeclType(Record);
// FIXME: Shouldn't we be able to perform this check even when the class
// type is dependent? Both gcc and edg can handle that.
if (!ClassType->isDependentType()) {
DeclarationName Name
= Context.DeclarationNames.getCXXDestructorName(
Context.getCanonicalType(ClassType));
if (NewFD->getDeclName() != Name) {
Diag(NewFD->getLocation(), diag::err_destructor_name);
NewFD->setInvalidDecl();
return Redeclaration;
}
}
} else if (CXXConversionDecl *Conversion
= dyn_cast<CXXConversionDecl>(NewFD)) {
ActOnConversionDeclarator(Conversion);
}
// Find any virtual functions that this function overrides.
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
if (!Method->isFunctionTemplateSpecialization() &&
!Method->getDescribedFunctionTemplate() &&
Method->isCanonicalDecl()) {
if (AddOverriddenMethods(Method->getParent(), Method)) {
// If the function was marked as "static", we have a problem.
if (NewFD->getStorageClass() == SC_Static) {
ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
}
}
}
if (Method->isStatic())
checkThisInStaticMemberFunctionType(Method);
}
// Extra checking for C++ overloaded operators (C++ [over.oper]).
if (NewFD->isOverloadedOperator() &&
CheckOverloadedOperatorDeclaration(NewFD)) {
NewFD->setInvalidDecl();
return Redeclaration;
}
// Extra checking for C++0x literal operators (C++0x [over.literal]).
if (NewFD->getLiteralIdentifier() &&
CheckLiteralOperatorDeclaration(NewFD)) {
NewFD->setInvalidDecl();
return Redeclaration;
}
// In C++, check default arguments now that we have merged decls. Unless
// the lexical context is the class, because in this case this is done
// during delayed parsing anyway.
if (!CurContext->isRecord())
CheckCXXDefaultArguments(NewFD);
// If this function declares a builtin function, check the type of this
// declaration against the expected type for the builtin.
if (unsigned BuiltinID = NewFD->getBuiltinID()) {
ASTContext::GetBuiltinTypeError Error;
LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
QualType T = Context.GetBuiltinType(BuiltinID, Error);
if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) {
// The type of this function differs from the type of the builtin,
// so forget about the builtin entirely.
Context.BuiltinInfo.forgetBuiltin(BuiltinID, Context.Idents);
}
}
// If this function is declared as being extern "C", then check to see if
// the function returns a UDT (class, struct, or union type) that is not C
// compatible, and if it does, warn the user.
// But, issue any diagnostic on the first declaration only.
if (Previous.empty() && NewFD->isExternC()) {
QualType R = NewFD->getReturnType();
if (R->isIncompleteType() && !R->isVoidType())
Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
<< NewFD << R;
else if (!R.isPODType(Context) && !R->isVoidType() &&
!R->isObjCObjectPointerType())
Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
}
}
return Redeclaration;
}
void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
// C++11 [basic.start.main]p3:
// A program that [...] declares main to be inline, static or
// constexpr is ill-formed.
// C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
// appear in a declaration of main.
// static main is not an error under C99, but we should warn about it.
// We accept _Noreturn main as an extension.
if (FD->getStorageClass() == SC_Static)
Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
? diag::err_static_main : diag::warn_static_main)
<< FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
if (FD->isInlineSpecified())
Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
<< FixItHint::CreateRemoval(DS.getInlineSpecLoc());
if (DS.isNoreturnSpecified()) {
SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
Diag(NoreturnLoc, diag::ext_noreturn_main);
Diag(NoreturnLoc, diag::note_main_remove_noreturn)
<< FixItHint::CreateRemoval(NoreturnRange);
}
if (FD->isConstexpr()) {
Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
<< FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
FD->setConstexpr(false);
}
if (getLangOpts().OpenCL) {
Diag(FD->getLocation(), diag::err_opencl_no_main)
<< FD->hasAttr<OpenCLKernelAttr>();
FD->setInvalidDecl();
return;
}
QualType T = FD->getType();
assert(T->isFunctionType() && "function decl is not of function type");
const FunctionType* FT = T->castAs<FunctionType>();
if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
// In C with GNU extensions we allow main() to have non-integer return
// type, but we should warn about the extension, and we disable the
// implicit-return-zero rule.
// GCC in C mode accepts qualified 'int'.
if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
FD->setHasImplicitReturnZero(true);
else {
Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
SourceRange RTRange = FD->getReturnTypeSourceRange();
if (RTRange.isValid())
Diag(RTRange.getBegin(), diag::note_main_change_return_type)
<< FixItHint::CreateReplacement(RTRange, "int");
}
} else {
// In C and C++, main magically returns 0 if you fall off the end;
// set the flag which tells us that.
// This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
// All the standards say that main() should return 'int'.
if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
FD->setHasImplicitReturnZero(true);
else {
// Otherwise, this is just a flat-out error.
SourceRange RTRange = FD->getReturnTypeSourceRange();
Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
<< (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
: FixItHint());
FD->setInvalidDecl(true);
}
}
// Treat protoless main() as nullary.
if (isa<FunctionNoProtoType>(FT)) return;
const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
unsigned nparams = FTP->getNumParams();
assert(FD->getNumParams() == nparams);
bool HasExtraParameters = (nparams > 3);
if (FTP->isVariadic()) {
Diag(FD->getLocation(), diag::ext_variadic_main);
// FIXME: if we had information about the location of the ellipsis, we
// could add a FixIt hint to remove it as a parameter.
}
// Darwin passes an undocumented fourth argument of type char**. If
// other platforms start sprouting these, the logic below will start
// getting shifty.
if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
HasExtraParameters = false;
if (HasExtraParameters) {
Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
FD->setInvalidDecl(true);
nparams = 3;
}
// FIXME: a lot of the following diagnostics would be improved
// if we had some location information about types.
QualType CharPP =
Context.getPointerType(Context.getPointerType(Context.CharTy));
QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
for (unsigned i = 0; i < nparams; ++i) {
QualType AT = FTP->getParamType(i);
bool mismatch = true;
if (Context.hasSameUnqualifiedType(AT, Expected[i]))
mismatch = false;
else if (Expected[i] == CharPP) {
// As an extension, the following forms are okay:
// char const **
// char const * const *
// char * const *
QualifierCollector qs;
const PointerType* PT;
if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
(PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
Context.CharTy)) {
qs.removeConst();
mismatch = !qs.empty();
}
}
if (mismatch) {
Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
// TODO: suggest replacing given type with expected type
FD->setInvalidDecl(true);
}
}
if (nparams == 1 && !FD->isInvalidDecl()) {
Diag(FD->getLocation(), diag::warn_main_one_arg);
}
if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
FD->setInvalidDecl();
}
}
void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
QualType T = FD->getType();
assert(T->isFunctionType() && "function decl is not of function type");
const FunctionType *FT = T->castAs<FunctionType>();
// Set an implicit return of 'zero' if the function can return some integral,
// enumeration, pointer or nullptr type.
if (FT->getReturnType()->isIntegralOrEnumerationType() ||
FT->getReturnType()->isAnyPointerType() ||
FT->getReturnType()->isNullPtrType())
// DllMain is exempt because a return value of zero means it failed.
if (FD->getName() != "DllMain")
FD->setHasImplicitReturnZero(true);
if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
FD->setInvalidDecl();
}
}
bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
// FIXME: Need strict checking. In C89, we need to check for
// any assignment, increment, decrement, function-calls, or
// commas outside of a sizeof. In C99, it's the same list,
// except that the aforementioned are allowed in unevaluated
// expressions. Everything else falls under the
// "may accept other forms of constant expressions" exception.
// (We never end up here for C++, so the constant expression
// rules there don't matter.)
const Expr *Culprit;
if (Init->isConstantInitializer(Context, false, &Culprit))
return false;
Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
<< Culprit->getSourceRange();
return true;
}
namespace {
// Visits an initialization expression to see if OrigDecl is evaluated in
// its own initialization and throws a warning if it does.
class SelfReferenceChecker
: public EvaluatedExprVisitor<SelfReferenceChecker> {
Sema &S;
Decl *OrigDecl;
bool isRecordType;
bool isPODType;
bool isReferenceType;
bool isInitList;
llvm::SmallVector<unsigned, 4> InitFieldIndex;
public:
typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
S(S), OrigDecl(OrigDecl) {
isPODType = false;
isRecordType = false;
isReferenceType = false;
isInitList = false;
if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
isPODType = VD->getType().isPODType(S.Context);
isRecordType = VD->getType()->isRecordType();
isReferenceType = VD->getType()->isReferenceType();
}
}
// For most expressions, just call the visitor. For initializer lists,
// track the index of the field being initialized since fields are
// initialized in order allowing use of previously initialized fields.
void CheckExpr(Expr *E) {
InitListExpr *InitList = dyn_cast<InitListExpr>(E);
if (!InitList) {
Visit(E);
return;
}
// Track and increment the index here.
isInitList = true;
InitFieldIndex.push_back(0);
for (auto Child : InitList->children()) {
CheckExpr(cast<Expr>(Child));
++InitFieldIndex.back();
}
InitFieldIndex.pop_back();
}
// Returns true if MemberExpr is checked and no futher checking is needed.
// Returns false if additional checking is required.
bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
llvm::SmallVector<FieldDecl*, 4> Fields;
Expr *Base = E;
bool ReferenceField = false;
// Get the field memebers used.
while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
if (!FD)
return false;
Fields.push_back(FD);
if (FD->getType()->isReferenceType())
ReferenceField = true;
Base = ME->getBase()->IgnoreParenImpCasts();
}
// Keep checking only if the base Decl is the same.
DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
if (!DRE || DRE->getDecl() != OrigDecl)
return false;
// A reference field can be bound to an unininitialized field.
if (CheckReference && !ReferenceField)
return true;
// Convert FieldDecls to their index number.
llvm::SmallVector<unsigned, 4> UsedFieldIndex;
for (const FieldDecl *I : llvm::reverse(Fields))
UsedFieldIndex.push_back(I->getFieldIndex());
// See if a warning is needed by checking the first difference in index
// numbers. If field being used has index less than the field being
// initialized, then the use is safe.
for (auto UsedIter = UsedFieldIndex.begin(),
UsedEnd = UsedFieldIndex.end(),
OrigIter = InitFieldIndex.begin(),
OrigEnd = InitFieldIndex.end();
UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
if (*UsedIter < *OrigIter)
return true;
if (*UsedIter > *OrigIter)
break;
}
// TODO: Add a different warning which will print the field names.
HandleDeclRefExpr(DRE);
return true;
}
// For most expressions, the cast is directly above the DeclRefExpr.
// For conditional operators, the cast can be outside the conditional
// operator if both expressions are DeclRefExpr's.
void HandleValue(Expr *E) {
E = E->IgnoreParens();
if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
HandleDeclRefExpr(DRE);
return;
}
if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
Visit(CO->getCond());
HandleValue(CO->getTrueExpr());
HandleValue(CO->getFalseExpr());
return;
}
if (BinaryConditionalOperator *BCO =
dyn_cast<BinaryConditionalOperator>(E)) {
Visit(BCO->getCond());
HandleValue(BCO->getFalseExpr());
return;
}
if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
HandleValue(OVE->getSourceExpr());
return;
}
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
if (BO->getOpcode() == BO_Comma) {
Visit(BO->getLHS());
HandleValue(BO->getRHS());
return;
}
}
if (isa<MemberExpr>(E)) {
if (isInitList) {
if (CheckInitListMemberExpr(cast<MemberExpr>(E),
false /*CheckReference*/))
return;
}
Expr *Base = E->IgnoreParenImpCasts();
while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
// Check for static member variables and don't warn on them.
if (!isa<FieldDecl>(ME->getMemberDecl()))
return;
Base = ME->getBase()->IgnoreParenImpCasts();
}
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
HandleDeclRefExpr(DRE);
return;
}
Visit(E);
}
// Reference types not handled in HandleValue are handled here since all
// uses of references are bad, not just r-value uses.
void VisitDeclRefExpr(DeclRefExpr *E) {
if (isReferenceType)
HandleDeclRefExpr(E);
}
void VisitImplicitCastExpr(ImplicitCastExpr *E) {
if (E->getCastKind() == CK_LValueToRValue) {
HandleValue(E->getSubExpr());
return;
}
Inherited::VisitImplicitCastExpr(E);
}
void VisitMemberExpr(MemberExpr *E) {
if (isInitList) {
if (CheckInitListMemberExpr(E, true /*CheckReference*/))
return;
}
// Don't warn on arrays since they can be treated as pointers.
if (E->getType()->canDecayToPointerType()) return;
// Warn when a non-static method call is followed by non-static member
// field accesses, which is followed by a DeclRefExpr.
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
bool Warn = (MD && !MD->isStatic());
Expr *Base = E->getBase()->IgnoreParenImpCasts();
while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
if (!isa<FieldDecl>(ME->getMemberDecl()))
Warn = false;
Base = ME->getBase()->IgnoreParenImpCasts();
}
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
if (Warn)
HandleDeclRefExpr(DRE);
return;
}
// The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
// Visit that expression.
Visit(Base);
}
void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
Expr *Callee = E->getCallee();
if (isa<UnresolvedLookupExpr>(Callee))
return Inherited::VisitCXXOperatorCallExpr(E);
Visit(Callee);
for (auto Arg: E->arguments())
HandleValue(Arg->IgnoreParenImpCasts());
}
void VisitUnaryOperator(UnaryOperator *E) {
// For POD record types, addresses of its own members are well-defined.
if (E->getOpcode() == UO_AddrOf && isRecordType &&
isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
if (!isPODType)
HandleValue(E->getSubExpr());
return;
}
if (E->isIncrementDecrementOp()) {
HandleValue(E->getSubExpr());
return;
}
Inherited::VisitUnaryOperator(E);
}
void VisitObjCMessageExpr(ObjCMessageExpr *E) { return; }
void VisitCXXConstructExpr(CXXConstructExpr *E) {
if (E->getConstructor()->isCopyConstructor()) {
Expr *ArgExpr = E->getArg(0);
if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
if (ILE->getNumInits() == 1)
ArgExpr = ILE->getInit(0);
if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
if (ICE->getCastKind() == CK_NoOp)
ArgExpr = ICE->getSubExpr();
HandleValue(ArgExpr);
return;
}
Inherited::VisitCXXConstructExpr(E);
}
void VisitCallExpr(CallExpr *E) {
// Treat std::move as a use.
if (E->getNumArgs() == 1) {
if (FunctionDecl *FD = E->getDirectCallee()) {
if (FD->isInStdNamespace() && FD->getIdentifier() &&
FD->getIdentifier()->isStr("move")) {
HandleValue(E->getArg(0));
return;
}
}
}
Inherited::VisitCallExpr(E);
}
void VisitBinaryOperator(BinaryOperator *E) {
if (E->isCompoundAssignmentOp()) {
HandleValue(E->getLHS());
Visit(E->getRHS());
return;
}
Inherited::VisitBinaryOperator(E);
}
// A custom visitor for BinaryConditionalOperator is needed because the
// regular visitor would check the condition and true expression separately
// but both point to the same place giving duplicate diagnostics.
void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
Visit(E->getCond());
Visit(E->getFalseExpr());
}
void HandleDeclRefExpr(DeclRefExpr *DRE) {
Decl* ReferenceDecl = DRE->getDecl();
if (OrigDecl != ReferenceDecl) return;
unsigned diag;
if (isReferenceType) {
diag = diag::warn_uninit_self_reference_in_reference_init;
} else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
diag = diag::warn_static_self_reference_in_init;
} else if (isa<TranslationUnitDecl>(OrigDecl->getDeclContext()) ||
isa<NamespaceDecl>(OrigDecl->getDeclContext()) ||
DRE->getDecl()->getType()->isRecordType()) {
diag = diag::warn_uninit_self_reference_in_init;
} else {
// Local variables will be handled by the CFG analysis.
return;
}
S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
S.PDiag(diag)
<< DRE->getNameInfo().getName()
<< OrigDecl->getLocation()
<< DRE->getSourceRange());
}
};
/// CheckSelfReference - Warns if OrigDecl is used in expression E.
static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
bool DirectInit) {
// Parameters arguments are occassionially constructed with itself,
// for instance, in recursive functions. Skip them.
if (isa<ParmVarDecl>(OrigDecl))
return;
E = E->IgnoreParens();
// Skip checking T a = a where T is not a record or reference type.
// Doing so is a way to silence uninitialized warnings.
if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
if (ICE->getCastKind() == CK_LValueToRValue)
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
if (DRE->getDecl() == OrigDecl)
return;
SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
}
}
QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
DeclarationName Name, QualType Type,
TypeSourceInfo *TSI,
SourceRange Range, bool DirectInit,
Expr *Init) {
bool IsInitCapture = !VDecl;
assert((!VDecl || !VDecl->isInitCapture()) &&
"init captures are expected to be deduced prior to initialization");
ArrayRef<Expr *> DeduceInits = Init;
if (DirectInit) {
if (auto *PL = dyn_cast<ParenListExpr>(Init))
DeduceInits = PL->exprs();
else if (auto *IL = dyn_cast<InitListExpr>(Init))
DeduceInits = IL->inits();
}
// Deduction only works if we have exactly one source expression.
if (DeduceInits.empty()) {
// It isn't possible to write this directly, but it is possible to
// end up in this situation with "auto x(some_pack...);"
Diag(Init->getLocStart(), IsInitCapture
? diag::err_init_capture_no_expression
: diag::err_auto_var_init_no_expression)
<< Name << Type << Range;
return QualType();
}
if (DeduceInits.size() > 1) {
Diag(DeduceInits[1]->getLocStart(),
IsInitCapture ? diag::err_init_capture_multiple_expressions
: diag::err_auto_var_init_multiple_expressions)
<< Name << Type << Range;
return QualType();
}
Expr *DeduceInit = DeduceInits[0];
if (DirectInit && isa<InitListExpr>(DeduceInit)) {
Diag(Init->getLocStart(), IsInitCapture
? diag::err_init_capture_paren_braces
: diag::err_auto_var_init_paren_braces)
<< isa<InitListExpr>(Init) << Name << Type << Range;
return QualType();
}
// Expressions default to 'id' when we're in a debugger.
bool DefaultedAnyToId = false;
if (getLangOpts().DebuggerCastResultToId &&
Init->getType() == Context.UnknownAnyTy && !IsInitCapture) {
ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
if (Result.isInvalid()) {
return QualType();
}
Init = Result.get();
DefaultedAnyToId = true;
}
QualType DeducedType;
if (DeduceAutoType(TSI, DeduceInit, DeducedType) == DAR_Failed) {
if (!IsInitCapture)
DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
else if (isa<InitListExpr>(Init))
Diag(Range.getBegin(),
diag::err_init_capture_deduction_failure_from_init_list)
<< Name
<< (DeduceInit->getType().isNull() ? TSI->getType()
: DeduceInit->getType())
<< DeduceInit->getSourceRange();
else
Diag(Range.getBegin(), diag::err_init_capture_deduction_failure)
<< Name << TSI->getType()
<< (DeduceInit->getType().isNull() ? TSI->getType()
: DeduceInit->getType())
<< DeduceInit->getSourceRange();
}
// Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
// 'id' instead of a specific object type prevents most of our usual
// checks.
// We only want to warn outside of template instantiations, though:
// inside a template, the 'id' could have come from a parameter.
if (ActiveTemplateInstantiations.empty() && !DefaultedAnyToId &&
!IsInitCapture && !DeducedType.isNull() && DeducedType->isObjCIdType()) {
SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
Diag(Loc, diag::warn_auto_var_is_id) << Name << Range;
}
return DeducedType;
}
/// AddInitializerToDecl - Adds the initializer Init to the
/// declaration dcl. If DirectInit is true, this is C++ direct
/// initialization rather than copy initialization.
void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
bool DirectInit, bool TypeMayContainAuto) {
// If there is no declaration, there was an error parsing it. Just ignore
// the initializer.
if (!RealDecl || RealDecl->isInvalidDecl()) {
CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
return;
}
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
// Pure-specifiers are handled in ActOnPureSpecifier.
Diag(Method->getLocation(), diag::err_member_function_initialization)
<< Method->getDeclName() << Init->getSourceRange();
Method->setInvalidDecl();
return;
}
VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
if (!VDecl) {
assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
RealDecl->setInvalidDecl();
return;
}
// C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
if (TypeMayContainAuto && VDecl->getType()->isUndeducedType()) {
// Attempt typo correction early so that the type of the init expression can
// be deduced based on the chosen correction if the original init contains a
// TypoExpr.
ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
if (!Res.isUsable()) {
RealDecl->setInvalidDecl();
return;
}
Init = Res.get();
QualType DeducedType = deduceVarTypeFromInitializer(
VDecl, VDecl->getDeclName(), VDecl->getType(),
VDecl->getTypeSourceInfo(), VDecl->getSourceRange(), DirectInit, Init);
if (DeducedType.isNull()) {
RealDecl->setInvalidDecl();
return;
}
VDecl->setType(DeducedType);
assert(VDecl->isLinkageValid());
// In ARC, infer lifetime.
if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
VDecl->setInvalidDecl();
// If this is a redeclaration, check that the type we just deduced matches
// the previously declared type.
if (VarDecl *Old = VDecl->getPreviousDecl()) {
// We never need to merge the type, because we cannot form an incomplete
// array of auto, nor deduce such a type.
MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/ false);
}
// Check the deduced type is valid for a variable declaration.
CheckVariableDeclarationType(VDecl);
if (VDecl->isInvalidDecl())
return;
}
// dllimport cannot be used on variable definitions.
if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
VDecl->setInvalidDecl();
return;
}
if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
// C99 6.7.8p5. C++ has no such restriction, but that is a defect.
Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
VDecl->setInvalidDecl();
return;
}
if (!VDecl->getType()->isDependentType()) {
// A definition must end up with a complete type, which means it must be
// complete with the restriction that an array type might be completed by
// the initializer; note that later code assumes this restriction.
QualType BaseDeclType = VDecl->getType();
if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
BaseDeclType = Array->getElementType();
if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
diag::err_typecheck_decl_incomplete_type)) {
RealDecl->setInvalidDecl();
return;
}
// The variable can not have an abstract class type.
if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
diag::err_abstract_type_in_decl,
AbstractVariableType))
VDecl->setInvalidDecl();
}
VarDecl *Def;
if ((Def = VDecl->getDefinition()) && Def != VDecl) {
NamedDecl *Hidden = nullptr;
if (!hasVisibleDefinition(Def, &Hidden) &&
(VDecl->getFormalLinkage() == InternalLinkage ||
VDecl->getDescribedVarTemplate() ||
VDecl->getNumTemplateParameterLists() ||
VDecl->getDeclContext()->isDependentContext())) {
// The previous definition is hidden, and multiple definitions are
// permitted (in separate TUs). Form another definition of it.
} else {
Diag(VDecl->getLocation(), diag::err_redefinition)
<< VDecl->getDeclName();
Diag(Def->getLocation(), diag::note_previous_definition);
VDecl->setInvalidDecl();
return;
}
}
if (getLangOpts().CPlusPlus) {
// C++ [class.static.data]p4
// If a static data member is of const integral or const
// enumeration type, its declaration in the class definition can
// specify a constant-initializer which shall be an integral
// constant expression (5.19). In that case, the member can appear
// in integral constant expressions. The member shall still be
// defined in a namespace scope if it is used in the program and the
// namespace scope definition shall not contain an initializer.
//
// We already performed a redefinition check above, but for static
// data members we also need to check whether there was an in-class
// declaration with an initializer.
if (VDecl->isStaticDataMember() && VDecl->getCanonicalDecl()->hasInit()) {
Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
<< VDecl->getDeclName();
Diag(VDecl->getCanonicalDecl()->getInit()->getExprLoc(),
diag::note_previous_initializer)
<< 0;
return;
}
if (VDecl->hasLocalStorage())
getCurFunction()->setHasBranchProtectedScope();
if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
VDecl->setInvalidDecl();
return;
}
}
// OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
// a kernel function cannot be initialized."
if (VDecl->getType().getAddressSpace() == LangAS::opencl_local) {
Diag(VDecl->getLocation(), diag::err_local_cant_init);
VDecl->setInvalidDecl();
return;
}
// Get the decls type and save a reference for later, since
// CheckInitializerTypes may change it.
QualType DclT = VDecl->getType(), SavT = DclT;
// Expressions default to 'id' when we're in a debugger
// and we are assigning it to a variable of Objective-C pointer type.
if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
Init->getType() == Context.UnknownAnyTy) {
ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
if (Result.isInvalid()) {
VDecl->setInvalidDecl();
return;
}
Init = Result.get();
}
// Perform the initialization.
ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
if (!VDecl->isInvalidDecl()) {
InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
InitializationKind Kind =
DirectInit
? CXXDirectInit
? InitializationKind::CreateDirect(VDecl->getLocation(),
Init->getLocStart(),
Init->getLocEnd())
: InitializationKind::CreateDirectList(VDecl->getLocation())
: InitializationKind::CreateCopy(VDecl->getLocation(),
Init->getLocStart());
MultiExprArg Args = Init;
if (CXXDirectInit)
Args = MultiExprArg(CXXDirectInit->getExprs(),
CXXDirectInit->getNumExprs());
// Try to correct any TypoExprs in the initialization arguments.
for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
ExprResult Res = CorrectDelayedTyposInExpr(
Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
return Init.Failed() ? ExprError() : E;
});
if (Res.isInvalid()) {
VDecl->setInvalidDecl();
} else if (Res.get() != Args[Idx]) {
Args[Idx] = Res.get();
}
}
if (VDecl->isInvalidDecl())
return;
InitializationSequence InitSeq(*this, Entity, Kind, Args);
ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
if (Result.isInvalid()) {
VDecl->setInvalidDecl();
return;
}
Init = Result.getAs<Expr>();
}
// Check for self-references within variable initializers.
// Variables declared within a function/method body (except for references)
// are handled by a dataflow analysis.
if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
VDecl->getType()->isReferenceType()) {
CheckSelfReference(*this, RealDecl, Init, DirectInit);
}
// If the type changed, it means we had an incomplete type that was
// completed by the initializer. For example:
// int ary[] = { 1, 3, 5 };
// "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
if (!VDecl->isInvalidDecl() && (DclT != SavT))
VDecl->setType(DclT);
if (!VDecl->isInvalidDecl()) {
checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
if (VDecl->hasAttr<BlocksAttr>())
checkRetainCycles(VDecl, Init);
// It is safe to assign a weak reference into a strong variable.
// Although this code can still have problems:
// id x = self.weakProp;
// id y = self.weakProp;
// we do not warn to warn spuriously when 'x' and 'y' are on separate
// paths through the function. This should be revisited if
// -Wrepeated-use-of-weak is made flow-sensitive.
if (VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong &&
!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
Init->getLocStart()))
getCurFunction()->markSafeWeakUse(Init);
}
// The initialization is usually a full-expression.
//
// FIXME: If this is a braced initialization of an aggregate, it is not
// an expression, and each individual field initializer is a separate
// full-expression. For instance, in:
//
// struct Temp { ~Temp(); };
// struct S { S(Temp); };
// struct T { S a, b; } t = { Temp(), Temp() }
//
// we should destroy the first Temp before constructing the second.
ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(),
false,
VDecl->isConstexpr());
if (Result.isInvalid()) {
VDecl->setInvalidDecl();
return;
}
Init = Result.get();
// Attach the initializer to the decl.
VDecl->setInit(Init);
if (VDecl->isLocalVarDecl()) {
// C99 6.7.8p4: All the expressions in an initializer for an object that has
// static storage duration shall be constant expressions or string literals.
// C++ does not have this restriction.
if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) {
const Expr *Culprit;
if (VDecl->getStorageClass() == SC_Static)
CheckForConstantInitializer(Init, DclT);
// C89 is stricter than C99 for non-static aggregate types.
// C89 6.5.7p3: All the expressions [...] in an initializer list
// for an object that has aggregate or union type shall be
// constant expressions.
else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
isa<InitListExpr>(Init) &&
!Init->isConstantInitializer(Context, false, &Culprit))
Diag(Culprit->getExprLoc(),
diag::ext_aggregate_init_not_constant)
<< Culprit->getSourceRange();
}
} else if (VDecl->isStaticDataMember() &&
VDecl->getLexicalDeclContext()->isRecord()) {
// This is an in-class initialization for a static data member, e.g.,
//
// struct S {
// static const int value = 17;
// };
// C++ [class.mem]p4:
// A member-declarator can contain a constant-initializer only
// if it declares a static member (9.4) of const integral or
// const enumeration type, see 9.4.2.
//
// C++11 [class.static.data]p3:
// If a non-volatile const static data member is of integral or
// enumeration type, its declaration in the class definition can
// specify a brace-or-equal-initializer in which every initalizer-clause
// that is an assignment-expression is a constant expression. A static
// data member of literal type can be declared in the class definition
// with the constexpr specifier; if so, its declaration shall specify a
// brace-or-equal-initializer in which every initializer-clause that is
// an assignment-expression is a constant expression.
// Do nothing on dependent types.
if (DclT->isDependentType()) {
// Allow any 'static constexpr' members, whether or not they are of literal
// type. We separately check that every constexpr variable is of literal
// type.
} else if (VDecl->isConstexpr()) {
// Require constness.
} else if (!DclT.isConstQualified()) {
Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
<< Init->getSourceRange();
VDecl->setInvalidDecl();
// We allow integer constant expressions in all cases.
} else if (DclT->isIntegralOrEnumerationType()) {
// Check whether the expression is a constant expression.
SourceLocation Loc;
if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
// In C++11, a non-constexpr const static data member with an
// in-class initializer cannot be volatile.
Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
else if (Init->isValueDependent())
; // Nothing to check.
else if (Init->isIntegerConstantExpr(Context, &Loc))
; // Ok, it's an ICE!
else if (Init->isEvaluatable(Context)) {
// If we can constant fold the initializer through heroics, accept it,
// but report this as a use of an extension for -pedantic.
Diag(Loc, diag::ext_in_class_initializer_non_constant)
<< Init->getSourceRange();
} else {
// Otherwise, this is some crazy unknown case. Report the issue at the
// location provided by the isIntegerConstantExpr failed check.
Diag(Loc, diag::err_in_class_initializer_non_constant)
<< Init->getSourceRange();
VDecl->setInvalidDecl();
}
// We allow foldable floating-point constants as an extension.
} else if (DclT->isFloatingType()) { // also permits complex, which is ok
// In C++98, this is a GNU extension. In C++11, it is not, but we support
// it anyway and provide a fixit to add the 'constexpr'.
if (getLangOpts().CPlusPlus11) {
Diag(VDecl->getLocation(),
diag::ext_in_class_initializer_float_type_cxx11)
<< DclT << Init->getSourceRange();
Diag(VDecl->getLocStart(),
diag::note_in_class_initializer_float_type_cxx11)
<< FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
} else {
Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
<< DclT << Init->getSourceRange();
if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
<< Init->getSourceRange();
VDecl->setInvalidDecl();
}
}
// Suggest adding 'constexpr' in C++11 for literal types.
} else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
<< DclT << Init->getSourceRange()
<< FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
VDecl->setConstexpr(true);
} else {
Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
<< DclT << Init->getSourceRange();
VDecl->setInvalidDecl();
}
} else if (VDecl->isFileVarDecl()) {
if (VDecl->getStorageClass() == SC_Extern &&
(!getLangOpts().CPlusPlus ||
!(Context.getBaseElementType(VDecl->getType()).isConstQualified() ||
VDecl->isExternC())) &&
!isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
Diag(VDecl->getLocation(), diag::warn_extern_init);
// C99 6.7.8p4. All file scoped initializers need to be constant.
if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
CheckForConstantInitializer(Init, DclT);
}
// We will represent direct-initialization similarly to copy-initialization:
// int x(1); -as-> int x = 1;
// ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
//
// Clients that want to distinguish between the two forms, can check for
// direct initializer using VarDecl::getInitStyle().
// A major benefit is that clients that don't particularly care about which
// exactly form was it (like the CodeGen) can handle both cases without
// special case code.
// C++ 8.5p11:
// The form of initialization (using parentheses or '=') is generally
// insignificant, but does matter when the entity being initialized has a
// class type.
if (CXXDirectInit) {
assert(DirectInit && "Call-style initializer must be direct init.");
VDecl->setInitStyle(VarDecl::CallInit);
} else if (DirectInit) {
// This must be list-initialization. No other way is direct-initialization.
VDecl->setInitStyle(VarDecl::ListInit);
}
CheckCompleteVariableDeclaration(VDecl);
}
/// ActOnInitializerError - Given that there was an error parsing an
/// initializer for the given declaration, try to return to some form
/// of sanity.
void Sema::ActOnInitializerError(Decl *D) {
// Our main concern here is re-establishing invariants like "a
// variable's type is either dependent or complete".
if (!D || D->isInvalidDecl()) return;
VarDecl *VD = dyn_cast<VarDecl>(D);
if (!VD) return;
// Auto types are meaningless if we can't make sense of the initializer.
if (ParsingInitForAutoVars.count(D)) {
D->setInvalidDecl();
return;
}
QualType Ty = VD->getType();
if (Ty->isDependentType()) return;
// Require a complete type.
if (RequireCompleteType(VD->getLocation(),
Context.getBaseElementType(Ty),
diag::err_typecheck_decl_incomplete_type)) {
VD->setInvalidDecl();
return;
}
// Require a non-abstract type.
if (RequireNonAbstractType(VD->getLocation(), Ty,
diag::err_abstract_type_in_decl,
AbstractVariableType)) {
VD->setInvalidDecl();
return;
}
// Don't bother complaining about constructors or destructors,
// though.
}
void Sema::ActOnUninitializedDecl(Decl *RealDecl,
bool TypeMayContainAuto) {
// If there is no declaration, there was an error parsing it. Just ignore it.
if (!RealDecl)
return;
if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
QualType Type = Var->getType();
// C++11 [dcl.spec.auto]p3
if (TypeMayContainAuto && Type->getContainedAutoType()) {
Diag(Var->getLocation(), diag::err_auto_var_requires_init)
<< Var->getDeclName() << Type;
Var->setInvalidDecl();
return;
}
// C++11 [class.static.data]p3: A static data member can be declared with
// the constexpr specifier; if so, its declaration shall specify
// a brace-or-equal-initializer.
// C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
// the definition of a variable [...] or the declaration of a static data
// member.
if (Var->isConstexpr() && !Var->isThisDeclarationADefinition()) {
if (Var->isStaticDataMember())
Diag(Var->getLocation(),
diag::err_constexpr_static_mem_var_requires_init)
<< Var->getDeclName();
else
Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
Var->setInvalidDecl();
return;
}
// C++ Concepts TS [dcl.spec.concept]p1: [...] A variable template
// definition having the concept specifier is called a variable concept. A
// concept definition refers to [...] a variable concept and its initializer.
if (Var->isConcept()) {
Diag(Var->getLocation(), diag::err_var_concept_not_initialized);
Var->setInvalidDecl();
return;
}
// OpenCL v1.1 s6.5.3: variables declared in the constant address space must
// be initialized.
if (!Var->isInvalidDecl() &&
Var->getType().getAddressSpace() == LangAS::opencl_constant &&
Var->getStorageClass() != SC_Extern && !Var->getInit()) {
Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
Var->setInvalidDecl();
return;
}
switch (Var->isThisDeclarationADefinition()) {
case VarDecl::Definition:
if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
break;
// We have an out-of-line definition of a static data member
// that has an in-class initializer, so we type-check this like
// a declaration.
//
// Fall through
case VarDecl::DeclarationOnly:
// It's only a declaration.
// Block scope. C99 6.7p7: If an identifier for an object is
// declared with no linkage (C99 6.2.2p6), the type for the
// object shall be complete.
if (!Type->isDependentType() && Var->isLocalVarDecl() &&
!Var->hasLinkage() && !Var->isInvalidDecl() &&
RequireCompleteType(Var->getLocation(), Type,
diag::err_typecheck_decl_incomplete_type))
Var->setInvalidDecl();
// Make sure that the type is not abstract.
if (!Type->isDependentType() && !Var->isInvalidDecl() &&
RequireNonAbstractType(Var->getLocation(), Type,
diag::err_abstract_type_in_decl,
AbstractVariableType))
Var->setInvalidDecl();
if (!Type->isDependentType() && !Var->isInvalidDecl() &&
Var->getStorageClass() == SC_PrivateExtern) {
Diag(Var->getLocation(), diag::warn_private_extern);
Diag(Var->getLocation(), diag::note_private_extern);
}
return;
case VarDecl::TentativeDefinition:
// File scope. C99 6.9.2p2: A declaration of an identifier for an
// object that has file scope without an initializer, and without a
// storage-class specifier or with the storage-class specifier "static",
// constitutes a tentative definition. Note: A tentative definition with
// external linkage is valid (C99 6.2.2p5).
if (!Var->isInvalidDecl()) {
if (const IncompleteArrayType *ArrayT
= Context.getAsIncompleteArrayType(Type)) {
if (RequireCompleteType(Var->getLocation(),
ArrayT->getElementType(),
diag::err_illegal_decl_array_incomplete_type))
Var->setInvalidDecl();
} else if (Var->getStorageClass() == SC_Static) {
// C99 6.9.2p3: If the declaration of an identifier for an object is
// a tentative definition and has internal linkage (C99 6.2.2p3), the
// declared type shall not be an incomplete type.
// NOTE: code such as the following
// static struct s;
// struct s { int a; };
// is accepted by gcc. Hence here we issue a warning instead of
// an error and we do not invalidate the static declaration.
// NOTE: to avoid multiple warnings, only check the first declaration.
if (Var->isFirstDecl())
RequireCompleteType(Var->getLocation(), Type,
diag::ext_typecheck_decl_incomplete_type);
}
}
// Record the tentative definition; we're done.
if (!Var->isInvalidDecl())
TentativeDefinitions.push_back(Var);
return;
}
// Provide a specific diagnostic for uninitialized variable
// definitions with incomplete array type.
if (Type->isIncompleteArrayType()) {
Diag(Var->getLocation(),
diag::err_typecheck_incomplete_array_needs_initializer);
Var->setInvalidDecl();
return;
}
// Provide a specific diagnostic for uninitialized variable
// definitions with reference type.
if (Type->isReferenceType()) {
Diag(Var->getLocation(), diag::err_reference_var_requires_init)
<< Var->getDeclName()
<< SourceRange(Var->getLocation(), Var->getLocation());
Var->setInvalidDecl();
return;
}
// Do not attempt to type-check the default initializer for a
// variable with dependent type.
if (Type->isDependentType())
return;
if (Var->isInvalidDecl())
return;
if (!Var->hasAttr<AliasAttr>()) {
if (RequireCompleteType(Var->getLocation(),
Context.getBaseElementType(Type),
diag::err_typecheck_decl_incomplete_type)) {
Var->setInvalidDecl();
return;
}
} else {
return;
}
// The variable can not have an abstract class type.
if (RequireNonAbstractType(Var->getLocation(), Type,
diag::err_abstract_type_in_decl,
AbstractVariableType)) {
Var->setInvalidDecl();
return;
}
// Check for jumps past the implicit initializer. C++0x
// clarifies that this applies to a "variable with automatic
// storage duration", not a "local variable".
// C++11 [stmt.dcl]p3
// A program that jumps from a point where a variable with automatic
// storage duration is not in scope to a point where it is in scope is
// ill-formed unless the variable has scalar type, class type with a
// trivial default constructor and a trivial destructor, a cv-qualified
// version of one of these types, or an array of one of the preceding
// types and is declared without an initializer.
if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
if (const RecordType *Record
= Context.getBaseElementType(Type)->getAs<RecordType>()) {
CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
// Mark the function for further checking even if the looser rules of
// C++11 do not require such checks, so that we can diagnose
// incompatibilities with C++98.
if (!CXXRecord->isPOD())
getCurFunction()->setHasBranchProtectedScope();
}
}
// C++03 [dcl.init]p9:
// If no initializer is specified for an object, and the
// object is of (possibly cv-qualified) non-POD class type (or
// array thereof), the object shall be default-initialized; if
// the object is of const-qualified type, the underlying class
// type shall have a user-declared default
// constructor. Otherwise, if no initializer is specified for
// a non- static object, the object and its subobjects, if
// any, have an indeterminate initial value); if the object
// or any of its subobjects are of const-qualified type, the
// program is ill-formed.
// C++0x [dcl.init]p11:
// If no initializer is specified for an object, the object is
// default-initialized; [...].
InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
InitializationKind Kind
= InitializationKind::CreateDefault(Var->getLocation());
InitializationSequence InitSeq(*this, Entity, Kind, None);
ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
if (Init.isInvalid())
Var->setInvalidDecl();
else if (Init.get()) {
Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
// This is important for template substitution.
Var->setInitStyle(VarDecl::CallInit);
}
CheckCompleteVariableDeclaration(Var);
}
}
void Sema::ActOnCXXForRangeDecl(Decl *D) {
VarDecl *VD = dyn_cast<VarDecl>(D);
if (!VD) {
Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
D->setInvalidDecl();
return;
}
VD->setCXXForRangeDecl(true);
// for-range-declaration cannot be given a storage class specifier.
int Error = -1;
switch (VD->getStorageClass()) {
case SC_None:
break;
case SC_Extern:
Error = 0;
break;
case SC_Static:
Error = 1;
break;
case SC_PrivateExtern:
Error = 2;
break;
case SC_Auto:
Error = 3;
break;
case SC_Register:
Error = 4;
break;
}
if (Error != -1) {
Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
<< VD->getDeclName() << Error;
D->setInvalidDecl();
}
}
StmtResult
Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
IdentifierInfo *Ident,
ParsedAttributes &Attrs,
SourceLocation AttrEnd) {
// C++1y [stmt.iter]p1:
// A range-based for statement of the form
// for ( for-range-identifier : for-range-initializer ) statement
// is equivalent to
// for ( auto&& for-range-identifier : for-range-initializer ) statement
DeclSpec DS(Attrs.getPool().getFactory());
const char *PrevSpec;
unsigned DiagID;
DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
getPrintingPolicy());
Declarator D(DS, Declarator::ForContext);
D.SetIdentifier(Ident, IdentLoc);
D.takeAttributes(Attrs, AttrEnd);
ParsedAttributes EmptyAttrs(Attrs.getPool().getFactory());
D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/false),
EmptyAttrs, IdentLoc);
Decl *Var = ActOnDeclarator(S, D);
cast<VarDecl>(Var)->setCXXForRangeDecl(true);
FinalizeDeclaration(Var);
return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
AttrEnd.isValid() ? AttrEnd : IdentLoc);
}
void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
if (var->isInvalidDecl()) return;
// In Objective-C, don't allow jumps past the implicit initialization of a
// local retaining variable.
if (getLangOpts().ObjC1 &&
var->hasLocalStorage()) {
switch (var->getType().getObjCLifetime()) {
case Qualifiers::OCL_None:
case Qualifiers::OCL_ExplicitNone:
case Qualifiers::OCL_Autoreleasing:
break;
case Qualifiers::OCL_Weak:
case Qualifiers::OCL_Strong:
getCurFunction()->setHasBranchProtectedScope();
break;
}
}
// Warn about externally-visible variables being defined without a
// prior declaration. We only want to do this for global
// declarations, but we also specifically need to avoid doing it for
// class members because the linkage of an anonymous class can
// change if it's later given a typedef name.
if (var->isThisDeclarationADefinition() &&
var->getDeclContext()->getRedeclContext()->isFileContext() &&
var->isExternallyVisible() && var->hasLinkage() &&
!getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
var->getLocation())) {
// Find a previous declaration that's not a definition.
VarDecl *prev = var->getPreviousDecl();
while (prev && prev->isThisDeclarationADefinition())
prev = prev->getPreviousDecl();
if (!prev)
Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
}
if (var->getTLSKind() == VarDecl::TLS_Static) {
const Expr *Culprit;
if (var->getType().isDestructedType()) {
// GNU C++98 edits for __thread, [basic.start.term]p3:
// The type of an object with thread storage duration shall not
// have a non-trivial destructor.
Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
if (getLangOpts().CPlusPlus11)
Diag(var->getLocation(), diag::note_use_thread_local);
} else if (getLangOpts().CPlusPlus && var->hasInit() &&
!var->getInit()->isConstantInitializer(
Context, var->getType()->isReferenceType(), &Culprit)) {
// GNU C++98 edits for __thread, [basic.start.init]p4:
// An object of thread storage duration shall not require dynamic
// initialization.
// FIXME: Need strict checking here.
Diag(Culprit->getExprLoc(), diag::err_thread_dynamic_init)
<< Culprit->getSourceRange();
if (getLangOpts().CPlusPlus11)
Diag(var->getLocation(), diag::note_use_thread_local);
}
}
// Apply section attributes and pragmas to global variables.
bool GlobalStorage = var->hasGlobalStorage();
if (GlobalStorage && var->isThisDeclarationADefinition() &&
ActiveTemplateInstantiations.empty()) {
PragmaStack<StringLiteral *> *Stack = nullptr;
int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
if (var->getType().isConstQualified())
Stack = &ConstSegStack;
else if (!var->getInit()) {
Stack = &BSSSegStack;
SectionFlags |= ASTContext::PSF_Write;
} else {
Stack = &DataSegStack;
SectionFlags |= ASTContext::PSF_Write;
}
if (Stack->CurrentValue && !var->hasAttr<SectionAttr>()) {
var->addAttr(SectionAttr::CreateImplicit(
Context, SectionAttr::Declspec_allocate,
Stack->CurrentValue->getString(), Stack->CurrentPragmaLocation));
}
if (const SectionAttr *SA = var->getAttr<SectionAttr>())
if (UnifySection(SA->getName(), SectionFlags, var))
var->dropAttr<SectionAttr>();
// Apply the init_seg attribute if this has an initializer. If the
// initializer turns out to not be dynamic, we'll end up ignoring this
// attribute.
if (CurInitSeg && var->getInit())
var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
CurInitSegLoc));
}
// All the following checks are C++ only.
if (!getLangOpts().CPlusPlus) return;
QualType type = var->getType();
if (type->isDependentType()) return;
// __block variables might require us to capture a copy-initializer.
if (var->hasAttr<BlocksAttr>()) {
// It's currently invalid to ever have a __block variable with an
// array type; should we diagnose that here?
// Regardless, we don't want to ignore array nesting when
// constructing this copy.
if (type->isStructureOrClassType()) {
EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
SourceLocation poi = var->getLocation();
Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
ExprResult result
= PerformMoveOrCopyInitialization(
InitializedEntity::InitializeBlock(poi, type, false),
var, var->getType(), varRef, /*AllowNRVO=*/true);
if (!result.isInvalid()) {
result = MaybeCreateExprWithCleanups(result);
Expr *init = result.getAs<Expr>();
Context.setBlockVarCopyInits(var, init);
}
}
}
Expr *Init = var->getInit();
bool IsGlobal = GlobalStorage && !var->isStaticLocal();
QualType baseType = Context.getBaseElementType(type);
if (!var->getDeclContext()->isDependentContext() &&
Init && !Init->isValueDependent()) {
if (IsGlobal && !var->isConstexpr() &&
!getDiagnostics().isIgnored(diag::warn_global_constructor,
var->getLocation())) {
// Warn about globals which don't have a constant initializer. Don't
// warn about globals with a non-trivial destructor because we already
// warned about them.
CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
if (!(RD && !RD->hasTrivialDestructor()) &&
!Init->isConstantInitializer(Context, baseType->isReferenceType()))
Diag(var->getLocation(), diag::warn_global_constructor)
<< Init->getSourceRange();
}
if (var->isConstexpr()) {
SmallVector<PartialDiagnosticAt, 8> Notes;
if (!var->evaluateValue(Notes) || !var->isInitICE()) {
SourceLocation DiagLoc = var->getLocation();
// If the note doesn't add any useful information other than a source
// location, fold it into the primary diagnostic.
if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
diag::note_invalid_subexpr_in_const_expr) {
DiagLoc = Notes[0].first;
Notes.clear();
}
Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
<< var << Init->getSourceRange();
for (unsigned I = 0, N = Notes.size(); I != N; ++I)
Diag(Notes[I].first, Notes[I].second);
}
} else if (var->isUsableInConstantExpressions(Context)) {
// Check whether the initializer of a const variable of integral or
// enumeration type is an ICE now, since we can't tell whether it was
// initialized by a constant expression if we check later.
var->checkInitIsICE();
}
}
// Require the destructor.
if (const RecordType *recordType = baseType->getAs<RecordType>())
FinalizeVarWithDestructor(var, recordType);
}
/// \brief Determines if a variable's alignment is dependent.
static bool hasDependentAlignment(VarDecl *VD) {
if (VD->getType()->isDependentType())
return true;
for (auto *I : VD->specific_attrs<AlignedAttr>())
if (I->isAlignmentDependent())
return true;
return false;
}
/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
/// any semantic actions necessary after any initializer has been attached.
void
Sema::FinalizeDeclaration(Decl *ThisDecl) {
// Note that we are no longer parsing the initializer for this declaration.
ParsingInitForAutoVars.erase(ThisDecl);
VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
if (!VD)
return;
checkAttributesAfterMerging(*this, *VD);
// Perform TLS alignment check here after attributes attached to the variable
// which may affect the alignment have been processed. Only perform the check
// if the target has a maximum TLS alignment (zero means no constraints).
if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
// Protect the check so that it's not performed on dependent types and
// dependent alignments (we can't determine the alignment in that case).
if (VD->getTLSKind() && !hasDependentAlignment(VD)) {
CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
if (Context.getDeclAlign(VD) > MaxAlignChars) {
Diag(VD->getLocation(), diag::err_tls_var_aligned_over_maximum)
<< (unsigned)Context.getDeclAlign(VD).getQuantity() << VD
<< (unsigned)MaxAlignChars.getQuantity();
}
}
}
// Static locals inherit dll attributes from their function.
if (VD->isStaticLocal()) {
if (FunctionDecl *FD =
dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
if (Attr *A = getDLLAttr(FD)) {
auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
NewAttr->setInherited(true);
VD->addAttr(NewAttr);
}
}
}
// Grab the dllimport or dllexport attribute off of the VarDecl.
const InheritableAttr *DLLAttr = getDLLAttr(VD);
// Imported static data members cannot be defined out-of-line.
if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
if (VD->isStaticDataMember() && VD->isOutOfLine() &&
VD->isThisDeclarationADefinition()) {
// We allow definitions of dllimport class template static data members
// with a warning.
CXXRecordDecl *Context =
cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
bool IsClassTemplateMember =
isa<ClassTemplatePartialSpecializationDecl>(Context) ||
Context->getDescribedClassTemplate();
Diag(VD->getLocation(),
IsClassTemplateMember
? diag::warn_attribute_dllimport_static_field_definition
: diag::err_attribute_dllimport_static_field_definition);
Diag(IA->getLocation(), diag::note_attribute);
if (!IsClassTemplateMember)
VD->setInvalidDecl();
}
}
// dllimport/dllexport variables cannot be thread local, their TLS index
// isn't exported with the variable.
if (DLLAttr && VD->getTLSKind()) {
auto *F = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
if (F && getDLLAttr(F)) {
assert(VD->isStaticLocal());
// But if this is a static local in a dlimport/dllexport function, the
// function will never be inlined, which means the var would never be
// imported, so having it marked import/export is safe.
} else {
Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
<< DLLAttr;
VD->setInvalidDecl();
}
}
if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
VD->dropAttr<UsedAttr>();
}
}
const DeclContext *DC = VD->getDeclContext();
// If there's a #pragma GCC visibility in scope, and this isn't a class
// member, set the visibility of this variable.
if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
AddPushedVisibilityAttribute(VD);
// FIXME: Warn on unused templates.
if (VD->isFileVarDecl() && !VD->getDescribedVarTemplate() &&
!isa<VarTemplatePartialSpecializationDecl>(VD))
MarkUnusedFileScopedDecl(VD);
// Now we have parsed the initializer and can update the table of magic
// tag values.
if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
!VD->getType()->isIntegralOrEnumerationType())
return;
for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
const Expr *MagicValueExpr = VD->getInit();
if (!MagicValueExpr) {
continue;
}
llvm::APSInt MagicValueInt;
if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
Diag(I->getRange().getBegin(),
diag::err_type_tag_for_datatype_not_ice)
<< LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
continue;
}
if (MagicValueInt.getActiveBits() > 64) {
Diag(I->getRange().getBegin(),
diag::err_type_tag_for_datatype_too_large)
<< LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
continue;
}
uint64_t MagicValue = MagicValueInt.getZExtValue();
RegisterTypeTagForDatatype(I->getArgumentKind(),
MagicValue,
I->getMatchingCType(),
I->getLayoutCompatible(),
I->getMustBeNull());
}
}
Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
ArrayRef<Decl *> Group) {
SmallVector<Decl*, 8> Decls;
if (DS.isTypeSpecOwned())
Decls.push_back(DS.getRepAsDecl());
DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
for (unsigned i = 0, e = Group.size(); i != e; ++i)
if (Decl *D = Group[i]) {
if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D))
if (!FirstDeclaratorInGroup)
FirstDeclaratorInGroup = DD;
Decls.push_back(D);
}
if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
handleTagNumbering(Tag, S);
if (FirstDeclaratorInGroup && !Tag->hasNameForLinkage() &&
getLangOpts().CPlusPlus)
Context.addDeclaratorForUnnamedTagDecl(Tag, FirstDeclaratorInGroup);
}
}
return BuildDeclaratorGroup(Decls, DS.containsPlaceholderType());
}
/// BuildDeclaratorGroup - convert a list of declarations into a declaration
/// group, performing any necessary semantic checking.
Sema::DeclGroupPtrTy
Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group,
bool TypeMayContainAuto) {
// C++0x [dcl.spec.auto]p7:
// If the type deduced for the template parameter U is not the same in each
// deduction, the program is ill-formed.
// FIXME: When initializer-list support is added, a distinction is needed
// between the deduced type U and the deduced type which 'auto' stands for.
// auto a = 0, b = { 1, 2, 3 };
// is legal because the deduced type U is 'int' in both cases.
if (TypeMayContainAuto && Group.size() > 1) {
QualType Deduced;
CanQualType DeducedCanon;
VarDecl *DeducedDecl = nullptr;
for (unsigned i = 0, e = Group.size(); i != e; ++i) {
if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) {
AutoType *AT = D->getType()->getContainedAutoType();
// Don't reissue diagnostics when instantiating a template.
if (AT && D->isInvalidDecl())
break;
QualType U = AT ? AT->getDeducedType() : QualType();
if (!U.isNull()) {
CanQualType UCanon = Context.getCanonicalType(U);
if (Deduced.isNull()) {
Deduced = U;
DeducedCanon = UCanon;
DeducedDecl = D;
} else if (DeducedCanon != UCanon) {
Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
diag::err_auto_different_deductions)
<< (unsigned)AT->getKeyword()
<< Deduced << DeducedDecl->getDeclName()
<< U << D->getDeclName()
<< DeducedDecl->getInit()->getSourceRange()
<< D->getInit()->getSourceRange();
D->setInvalidDecl();
break;
}
}
}
}
}
ActOnDocumentableDecls(Group);
return DeclGroupPtrTy::make(
DeclGroupRef::Create(Context, Group.data(), Group.size()));
}
void Sema::ActOnDocumentableDecl(Decl *D) {
ActOnDocumentableDecls(D);
}
void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
// Don't parse the comment if Doxygen diagnostics are ignored.
if (Group.empty() || !Group[0])
return;
if (Diags.isIgnored(diag::warn_doc_param_not_found,
Group[0]->getLocation()) &&
Diags.isIgnored(diag::warn_unknown_comment_command_name,
Group[0]->getLocation()))
return;
if (Group.size() >= 2) {
// This is a decl group. Normally it will contain only declarations
// produced from declarator list. But in case we have any definitions or
// additional declaration references:
// 'typedef struct S {} S;'
// 'typedef struct S *S;'
// 'struct S *pS;'
// FinalizeDeclaratorGroup adds these as separate declarations.
Decl *MaybeTagDecl = Group[0];
if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
Group = Group.slice(1);
}
}
// See if there are any new comments that are not attached to a decl.
ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
if (!Comments.empty() &&
!Comments.back()->isAttached()) {
// There is at least one comment that not attached to a decl.
// Maybe it should be attached to one of these decls?
//
// Note that this way we pick up not only comments that precede the
// declaration, but also comments that *follow* the declaration -- thanks to
// the lookahead in the lexer: we've consumed the semicolon and looked
// ahead through comments.
for (unsigned i = 0, e = Group.size(); i != e; ++i)
Context.getCommentForDecl(Group[i], &PP);
}
}
/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
/// to introduce parameters into function prototype scope.
Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
const DeclSpec &DS = D.getDeclSpec();
// Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
// C++03 [dcl.stc]p2 also permits 'auto'.
StorageClass SC = SC_None;
if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
SC = SC_Register;
} else if (getLangOpts().CPlusPlus &&
DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
SC = SC_Auto;
} else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
Diag(DS.getStorageClassSpecLoc(),
diag::err_invalid_storage_class_in_func_decl);
D.getMutableDeclSpec().ClearStorageClassSpecs();
}
if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
<< DeclSpec::getSpecifierName(TSCS);
if (DS.isConstexprSpecified())
Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
<< 0;
if (DS.isConceptSpecified())
Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
DiagnoseFunctionSpecifiers(DS);
TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
QualType parmDeclType = TInfo->getType();
if (getLangOpts().CPlusPlus) {
// Check that there are no default arguments inside the type of this
// parameter.
CheckExtraCXXDefaultArguments(D);
// Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
if (D.getCXXScopeSpec().isSet()) {
Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
<< D.getCXXScopeSpec().getRange();
D.getCXXScopeSpec().clear();
}
}
// Ensure we have a valid name
IdentifierInfo *II = nullptr;
if (D.hasName()) {
II = D.getIdentifier();
if (!II) {
Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
<< GetNameForDeclarator(D).getName();
D.setInvalidType(true);
}
}
// Check for redeclaration of parameters, e.g. int foo(int x, int x);
if (II) {
LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
ForRedeclaration);
LookupName(R, S);
if (R.isSingleResult()) {
NamedDecl *PrevDecl = R.getFoundDecl();
if (PrevDecl->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
// Just pretend that we didn't see the previous declaration.
PrevDecl = nullptr;
} else if (S->isDeclScope(PrevDecl)) {
Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
// Recover by removing the name
II = nullptr;
D.SetIdentifier(nullptr, D.getIdentifierLoc());
D.setInvalidType(true);
}
}
}
// Temporarily put parameter variables in the translation unit, not
// the enclosing context. This prevents them from accidentally
// looking like class members in C++.
ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(),
D.getLocStart(),
D.getIdentifierLoc(), II,
parmDeclType, TInfo,
SC);
if (D.isInvalidType())
New->setInvalidDecl();
assert(S->isFunctionPrototypeScope());
assert(S->getFunctionPrototypeDepth() >= 1);
New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
S->getNextFunctionPrototypeIndex());
// Add the parameter declaration into this scope.
S->AddDecl(New);
if (II)
IdResolver.AddDecl(New);
ProcessDeclAttributes(S, New, D);
if (D.getDeclSpec().isModulePrivateSpecified())
Diag(New->getLocation(), diag::err_module_private_local)
<< 1 << New->getDeclName()
<< SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
<< FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
if (New->hasAttr<BlocksAttr>()) {
Diag(New->getLocation(), diag::err_block_on_nonlocal);
}
return New;
}
/// \brief Synthesizes a variable for a parameter arising from a
/// typedef.
ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
SourceLocation Loc,
QualType T) {
/* FIXME: setting StartLoc == Loc.
Would it be worth to modify callers so as to provide proper source
location for the unnamed parameters, embedding the parameter's type? */
ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
T, Context.getTrivialTypeSourceInfo(T, Loc),
SC_None, nullptr);
Param->setImplicit();
return Param;
}
void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param,
ParmVarDecl * const *ParamEnd) {
// Don't diagnose unused-parameter errors in template instantiations; we
// will already have done so in the template itself.
if (!ActiveTemplateInstantiations.empty())
return;
for (; Param != ParamEnd; ++Param) {
if (!(*Param)->isReferenced() && (*Param)->getDeclName() &&
!(*Param)->hasAttr<UnusedAttr>()) {
Diag((*Param)->getLocation(), diag::warn_unused_parameter)
<< (*Param)->getDeclName();
}
}
}
void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param,
ParmVarDecl * const *ParamEnd,
QualType ReturnTy,
NamedDecl *D) {
if (LangOpts.NumLargeByValueCopy == 0) // No check.
return;
// Warn if the return value is pass-by-value and larger than the specified
// threshold.
if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
if (Size > LangOpts.NumLargeByValueCopy)
Diag(D->getLocation(), diag::warn_return_value_size)
<< D->getDeclName() << Size;
}
// Warn if any parameter is pass-by-value and larger than the specified
// threshold.
for (; Param != ParamEnd; ++Param) {
QualType T = (*Param)->getType();
if (T->isDependentType() || !T.isPODType(Context))
continue;
unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
if (Size > LangOpts.NumLargeByValueCopy)
Diag((*Param)->getLocation(), diag::warn_parameter_size)
<< (*Param)->getDeclName() << Size;
}
}
ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
SourceLocation NameLoc, IdentifierInfo *Name,
QualType T, TypeSourceInfo *TSInfo,
StorageClass SC) {
// In ARC, infer a lifetime qualifier for appropriate parameter types.
if (getLangOpts().ObjCAutoRefCount &&
T.getObjCLifetime() == Qualifiers::OCL_None &&
T->isObjCLifetimeType()) {
Qualifiers::ObjCLifetime lifetime;
// Special cases for arrays:
// - if it's const, use __unsafe_unretained
// - otherwise, it's an error
if (T->isArrayType()) {
if (!T.isConstQualified()) {
DelayedDiagnostics.add(
sema::DelayedDiagnostic::makeForbiddenType(
NameLoc, diag::err_arc_array_param_no_ownership, T, false));
}
lifetime = Qualifiers::OCL_ExplicitNone;
} else {
lifetime = T->getObjCARCImplicitLifetime();
}
T = Context.getLifetimeQualifiedType(T, lifetime);
}
ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
Context.getAdjustedParameterType(T),
TSInfo, SC, nullptr);
// Parameters can not be abstract class types.
// For record types, this is done by the AbstractClassUsageDiagnoser once
// the class has been completely parsed.
if (!CurContext->isRecord() &&
RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
AbstractParamType))
New->setInvalidDecl();
// Parameter declarators cannot be interface types. All ObjC objects are
// passed by reference.
if (T->isObjCObjectType()) {
SourceLocation TypeEndLoc = TSInfo->getTypeLoc().getLocEnd();
Diag(NameLoc,
diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
<< FixItHint::CreateInsertion(TypeEndLoc, "*");
T = Context.getObjCObjectPointerType(T);
New->setType(T);
}
// ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
// duration shall not be qualified by an address-space qualifier."
// Since all parameters have automatic store duration, they can not have
// an address space.
if (T.getAddressSpace() != 0) {
// OpenCL allows function arguments declared to be an array of a type
// to be qualified with an address space.
if (!(getLangOpts().OpenCL && T->isArrayType())) {
Diag(NameLoc, diag::err_arg_with_address_space);
New->setInvalidDecl();
}
}
return New;
}
void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
SourceLocation LocAfterDecls) {
DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
// Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
// for a K&R function.
if (!FTI.hasPrototype) {
for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
--i;
if (FTI.Params[i].Param == nullptr) {
SmallString<256> Code;
llvm::raw_svector_ostream(Code)
<< " int " << FTI.Params[i].Ident->getName() << ";\n";
Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
<< FTI.Params[i].Ident
<< FixItHint::CreateInsertion(LocAfterDecls, Code);
// Implicitly declare the argument as type 'int' for lack of a better
// type.
AttributeFactory attrs;
DeclSpec DS(attrs);
const char* PrevSpec; // unused
unsigned DiagID; // unused
DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
DiagID, Context.getPrintingPolicy());
// Use the identifier location for the type source range.
DS.SetRangeStart(FTI.Params[i].IdentLoc);
DS.SetRangeEnd(FTI.Params[i].IdentLoc);
Declarator ParamD(DS, Declarator::KNRTypeListContext);
ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
}
}
}
}
Decl *
Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D,
MultiTemplateParamsArg TemplateParameterLists,
SkipBodyInfo *SkipBody) {
assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
assert(D.isFunctionDeclarator() && "Not a function declarator!");
Scope *ParentScope = FnBodyScope->getParent();
D.setFunctionDefinitionKind(FDK_Definition);
Decl *DP = HandleDeclarator(ParentScope, D, TemplateParameterLists);
return ActOnStartOfFunctionDef(FnBodyScope, DP, SkipBody);
}
void Sema::ActOnFinishInlineMethodDef(CXXMethodDecl *D) {
Consumer.HandleInlineMethodDefinition(D);
}
static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
const FunctionDecl*& PossibleZeroParamPrototype) {
// Don't warn about invalid declarations.
if (FD->isInvalidDecl())
return false;
// Or declarations that aren't global.
if (!FD->isGlobal())
return false;
// Don't warn about C++ member functions.
if (isa<CXXMethodDecl>(FD))
return false;
// Don't warn about 'main'.
if (FD->isMain())
return false;
// Don't warn about inline functions.
if (FD->isInlined())
return false;
// Don't warn about function templates.
if (FD->getDescribedFunctionTemplate())
return false;
// Don't warn about function template specializations.
if (FD->isFunctionTemplateSpecialization())
return false;
// Don't warn for OpenCL kernels.
if (FD->hasAttr<OpenCLKernelAttr>())
return false;
// Don't warn on explicitly deleted functions.
if (FD->isDeleted())
return false;
bool MissingPrototype = true;
for (const FunctionDecl *Prev = FD->getPreviousDecl();
Prev; Prev = Prev->getPreviousDecl()) {
// Ignore any declarations that occur in function or method
// scope, because they aren't visible from the header.
if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
continue;
MissingPrototype = !Prev->getType()->isFunctionProtoType();
if (FD->getNumParams() == 0)
PossibleZeroParamPrototype = Prev;
break;
}
return MissingPrototype;
}
void
Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
const FunctionDecl *EffectiveDefinition,
SkipBodyInfo *SkipBody) {
// Don't complain if we're in GNU89 mode and the previous definition
// was an extern inline function.
const FunctionDecl *Definition = EffectiveDefinition;
if (!Definition)
if (!FD->isDefined(Definition))
return;
if (canRedefineFunction(Definition, getLangOpts()))
return;
// If we don't have a visible definition of the function, and it's inline or
// a template, skip the new definition.
if (SkipBody && !hasVisibleDefinition(Definition) &&
(Definition->getFormalLinkage() == InternalLinkage ||
Definition->isInlined() ||
Definition->getDescribedFunctionTemplate() ||
Definition->getNumTemplateParameterLists())) {
SkipBody->ShouldSkip = true;
if (auto *TD = Definition->getDescribedFunctionTemplate())
makeMergedDefinitionVisible(TD, FD->getLocation());
else
makeMergedDefinitionVisible(const_cast<FunctionDecl*>(Definition),
FD->getLocation());
return;
}
if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
Definition->getStorageClass() == SC_Extern)
Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
<< FD->getDeclName() << getLangOpts().CPlusPlus;
else
Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
Diag(Definition->getLocation(), diag::note_previous_definition);
FD->setInvalidDecl();
}
static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
Sema &S) {
CXXRecordDecl *const LambdaClass = CallOperator->getParent();
LambdaScopeInfo *LSI = S.PushLambdaScope();
LSI->CallOperator = CallOperator;
LSI->Lambda = LambdaClass;
LSI->ReturnType = CallOperator->getReturnType();
const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
if (LCD == LCD_None)
LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
else if (LCD == LCD_ByCopy)
LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
else if (LCD == LCD_ByRef)
LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
DeclarationNameInfo DNI = CallOperator->getNameInfo();
LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
LSI->Mutable = !CallOperator->isConst();
// Add the captures to the LSI so they can be noted as already
// captured within tryCaptureVar.
auto I = LambdaClass->field_begin();
for (const auto &C : LambdaClass->captures()) {
if (C.capturesVariable()) {
VarDecl *VD = C.getCapturedVar();
if (VD->isInitCapture())
S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
QualType CaptureType = VD->getType();
const bool ByRef = C.getCaptureKind() == LCK_ByRef;
LSI->addCapture(VD, /*IsBlock*/false, ByRef,
/*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
/*EllipsisLoc*/C.isPackExpansion()
? C.getEllipsisLoc() : SourceLocation(),
CaptureType, /*Expr*/ nullptr);
} else if (C.capturesThis()) {
LSI->addThisCapture(/*Nested*/ false, C.getLocation(),
S.getCurrentThisType(), /*Expr*/ nullptr);
} else {
LSI->addVLATypeCapture(C.getLocation(), I->getType());
}
++I;
}
}
Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
SkipBodyInfo *SkipBody) {
// Clear the last template instantiation error context.
LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation();
if (!D)
return D;
FunctionDecl *FD = nullptr;
if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
FD = FunTmpl->getTemplatedDecl();
else
FD = cast<FunctionDecl>(D);
// See if this is a redefinition.
if (!FD->isLateTemplateParsed()) {
CheckForFunctionRedefinition(FD, nullptr, SkipBody);
// If we're skipping the body, we're done. Don't enter the scope.
if (SkipBody && SkipBody->ShouldSkip)
return D;
}
// If we are instantiating a generic lambda call operator, push
// a LambdaScopeInfo onto the function stack. But use the information
// that's already been calculated (ActOnLambdaExpr) to prime the current
// LambdaScopeInfo.
// When the template operator is being specialized, the LambdaScopeInfo,
// has to be properly restored so that tryCaptureVariable doesn't try
// and capture any new variables. In addition when calculating potential
// captures during transformation of nested lambdas, it is necessary to
// have the LSI properly restored.
if (isGenericLambdaCallOperatorSpecialization(FD)) {
assert(ActiveTemplateInstantiations.size() &&
"There should be an active template instantiation on the stack "
"when instantiating a generic lambda!");
RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
}
else
// Enter a new function scope
PushFunctionScope();
// Builtin functions cannot be defined.
if (unsigned BuiltinID = FD->getBuiltinID()) {
if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
!Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
FD->setInvalidDecl();
}
}
// The return type of a function definition must be complete
// (C99 6.9.1p3, C++ [dcl.fct]p6).
QualType ResultType = FD->getReturnType();
if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
!FD->isInvalidDecl() &&
RequireCompleteType(FD->getLocation(), ResultType,
diag::err_func_def_incomplete_result))
FD->setInvalidDecl();
if (FnBodyScope)
PushDeclContext(FnBodyScope, FD);
// Check the validity of our function parameters
CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(),
/*CheckParameterNames=*/true);
// Introduce our parameters into the function scope
for (auto Param : FD->params()) {
Param->setOwningFunction(FD);
// If this has an identifier, add it to the scope stack.
if (Param->getIdentifier() && FnBodyScope) {
CheckShadow(FnBodyScope, Param);
PushOnScopeChains(Param, FnBodyScope);
}
}
// If we had any tags defined in the function prototype,
// introduce them into the function scope.
if (FnBodyScope) {
for (ArrayRef<NamedDecl *>::iterator
I = FD->getDeclsInPrototypeScope().begin(),
E = FD->getDeclsInPrototypeScope().end();
I != E; ++I) {
NamedDecl *D = *I;
// Some of these decls (like enums) may have been pinned to the
// translation unit for lack of a real context earlier. If so, remove
// from the translation unit and reattach to the current context.
if (D->getLexicalDeclContext() == Context.getTranslationUnitDecl()) {
// Is the decl actually in the context?
for (const auto *DI : Context.getTranslationUnitDecl()->decls()) {
if (DI == D) {
Context.getTranslationUnitDecl()->removeDecl(D);
break;
}
}
// Either way, reassign the lexical decl context to our FunctionDecl.
D->setLexicalDeclContext(CurContext);
}
// If the decl has a non-null name, make accessible in the current scope.
if (!D->getName().empty())
PushOnScopeChains(D, FnBodyScope, /*AddToContext=*/false);
// Similarly, dive into enums and fish their constants out, making them
// accessible in this scope.
if (auto *ED = dyn_cast<EnumDecl>(D)) {
for (auto *EI : ED->enumerators())
PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
}
}
}
// Ensure that the function's exception specification is instantiated.
if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
ResolveExceptionSpec(D->getLocation(), FPT);
// dllimport cannot be applied to non-inline function definitions.
if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
!FD->isTemplateInstantiation()) {
assert(!FD->hasAttr<DLLExportAttr>());
Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
FD->setInvalidDecl();
return D;
}
// We want to attach documentation to original Decl (which might be
// a function template).
ActOnDocumentableDecl(D);
if (getCurLexicalContext()->isObjCContainer() &&
getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
return D;
}
/// \brief Given the set of return statements within a function body,
/// compute the variables that are subject to the named return value
/// optimization.
///
/// Each of the variables that is subject to the named return value
/// optimization will be marked as NRVO variables in the AST, and any
/// return statement that has a marked NRVO variable as its NRVO candidate can
/// use the named return value optimization.
///
/// This function applies a very simplistic algorithm for NRVO: if every return
/// statement in the scope of a variable has the same NRVO candidate, that
/// candidate is an NRVO variable.
void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
ReturnStmt **Returns = Scope->Returns.data();
for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
if (!NRVOCandidate->isNRVOVariable())
Returns[I]->setNRVOCandidate(nullptr);
}
}
}
bool Sema::canDelayFunctionBody(const Declarator &D) {
// We can't delay parsing the body of a constexpr function template (yet).
if (D.getDeclSpec().isConstexprSpecified())
return false;
// We can't delay parsing the body of a function template with a deduced
// return type (yet).
if (D.getDeclSpec().containsPlaceholderType()) {
// If the placeholder introduces a non-deduced trailing return type,
// we can still delay parsing it.
if (D.getNumTypeObjects()) {
const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
if (Outer.Kind == DeclaratorChunk::Function &&
Outer.Fun.hasTrailingReturnType()) {
QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
return Ty.isNull() || !Ty->isUndeducedType();
}
}
return false;
}
return true;
}
bool Sema::canSkipFunctionBody(Decl *D) {
// We cannot skip the body of a function (or function template) which is
// constexpr, since we may need to evaluate its body in order to parse the
// rest of the file.
// We cannot skip the body of a function with an undeduced return type,
// because any callers of that function need to know the type.
if (const FunctionDecl *FD = D->getAsFunction())
if (FD->isConstexpr() || FD->getReturnType()->isUndeducedType())
return false;
return Consumer.shouldSkipFunctionBody(D);
}
Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl))
FD->setHasSkippedBody();
else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl))
MD->setHasSkippedBody();
return ActOnFinishFunctionBody(Decl, nullptr);
}
Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
return ActOnFinishFunctionBody(D, BodyArg, false);
}
Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
bool IsInstantiation) {
FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
if (getLangOpts().Coroutines && !getCurFunction()->CoroutineStmts.empty())
CheckCompletedCoroutineBody(FD, Body);
if (FD) {
FD->setBody(Body);
if (getLangOpts().CPlusPlus14 && !FD->isInvalidDecl() && Body &&
!FD->isDependentContext() && FD->getReturnType()->isUndeducedType()) {
// If the function has a deduced result type but contains no 'return'
// statements, the result type as written must be exactly 'auto', and
// the deduced result type is 'void'.
if (!FD->getReturnType()->getAs<AutoType>()) {
Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
<< FD->getReturnType();
FD->setInvalidDecl();
} else {
// Substitute 'void' for the 'auto' in the type.
TypeLoc ResultType = getReturnTypeLoc(FD);
Context.adjustDeducedFunctionResultType(
FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
}
} else if (getLangOpts().CPlusPlus11 && isLambdaCallOperator(FD)) {
auto *LSI = getCurLambda();
if (LSI->HasImplicitReturnType) {
deduceClosureReturnType(*LSI);
// C++11 [expr.prim.lambda]p4:
// [...] if there are no return statements in the compound-statement
// [the deduced type is] the type void
QualType RetType =
LSI->ReturnType.isNull() ? Context.VoidTy : LSI->ReturnType;
// Update the return type to the deduced type.
const FunctionProtoType *Proto =
FD->getType()->getAs<FunctionProtoType>();
FD->setType(Context.getFunctionType(RetType, Proto->getParamTypes(),
Proto->getExtProtoInfo()));
}
}
// The only way to be included in UndefinedButUsed is if there is an
// ODR use before the definition. Avoid the expensive map lookup if this
// is the first declaration.
if (!FD->isFirstDecl() && FD->getPreviousDecl()->isUsed()) {
if (!FD->isExternallyVisible())
UndefinedButUsed.erase(FD);
else if (FD->isInlined() &&
!LangOpts.GNUInline &&
(!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>()))
UndefinedButUsed.erase(FD);
}
// If the function implicitly returns zero (like 'main') or is naked,
// don't complain about missing return statements.
if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
WP.disableCheckFallThrough();
// MSVC permits the use of pure specifier (=0) on function definition,
// defined at class scope, warn about this non-standard construct.
if (getLangOpts().MicrosoftExt && FD->isPure() && FD->isCanonicalDecl())
Diag(FD->getLocation(), diag::ext_pure_function_definition);
if (!FD->isInvalidDecl()) {
// Don't diagnose unused parameters of defaulted or deleted functions.
if (!FD->isDeleted() && !FD->isDefaulted())
DiagnoseUnusedParameters(FD->param_begin(), FD->param_end());
DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(),
FD->getReturnType(), FD);
// If this is a structor, we need a vtable.
if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
MarkVTableUsed(FD->getLocation(), Constructor->getParent());
else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
MarkVTableUsed(FD->getLocation(), Destructor->getParent());
// Try to apply the named return value optimization. We have to check
// if we can do this here because lambdas keep return statements around
// to deduce an implicit return type.
if (getLangOpts().CPlusPlus && FD->getReturnType()->isRecordType() &&
!FD->isDependentContext())
computeNRVO(Body, getCurFunction());
}
// GNU warning -Wmissing-prototypes:
// Warn if a global function is defined without a previous
// prototype declaration. This warning is issued even if the
// definition itself provides a prototype. The aim is to detect
// global functions that fail to be declared in header files.
const FunctionDecl *PossibleZeroParamPrototype = nullptr;
if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) {
Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
if (PossibleZeroParamPrototype) {
// We found a declaration that is not a prototype,
// but that could be a zero-parameter prototype
if (TypeSourceInfo *TI =
PossibleZeroParamPrototype->getTypeSourceInfo()) {
TypeLoc TL = TI->getTypeLoc();
if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
Diag(PossibleZeroParamPrototype->getLocation(),
diag::note_declaration_not_a_prototype)
<< PossibleZeroParamPrototype
<< FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
}
}
}
if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
const CXXMethodDecl *KeyFunction;
if (MD->isOutOfLine() && (MD = MD->getCanonicalDecl()) &&
MD->isVirtual() &&
(KeyFunction = Context.getCurrentKeyFunction(MD->getParent())) &&
MD == KeyFunction->getCanonicalDecl()) {
// Update the key-function state if necessary for this ABI.
if (FD->isInlined() &&
!Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
Context.setNonKeyFunction(MD);
// If the newly-chosen key function is already defined, then we
// need to mark the vtable as used retroactively.
KeyFunction = Context.getCurrentKeyFunction(MD->getParent());
const FunctionDecl *Definition;
if (KeyFunction && KeyFunction->isDefined(Definition))
MarkVTableUsed(Definition->getLocation(), MD->getParent(), true);
} else {
// We just defined they key function; mark the vtable as used.
MarkVTableUsed(FD->getLocation(), MD->getParent(), true);
}
}
}
assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
"Function parsing confused");
} else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
assert(MD == getCurMethodDecl() && "Method parsing confused");
MD->setBody(Body);
if (!MD->isInvalidDecl()) {
DiagnoseUnusedParameters(MD->param_begin(), MD->param_end());
DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(),
MD->getReturnType(), MD);
if (Body)
computeNRVO(Body, getCurFunction());
}
if (getCurFunction()->ObjCShouldCallSuper) {
Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call)
<< MD->getSelector().getAsString();
getCurFunction()->ObjCShouldCallSuper = false;
}
if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
const ObjCMethodDecl *InitMethod = nullptr;
bool isDesignated =
MD->isDesignatedInitializerForTheInterface(&InitMethod);
assert(isDesignated && InitMethod);
(void)isDesignated;
auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
auto IFace = MD->getClassInterface();
if (!IFace)
return false;
auto SuperD = IFace->getSuperClass();
if (!SuperD)
return false;
return SuperD->getIdentifier() ==
NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
};
// Don't issue this warning for unavailable inits or direct subclasses
// of NSObject.
if (!MD->isUnavailable() && !superIsNSObject(MD)) {
Diag(MD->getLocation(),
diag::warn_objc_designated_init_missing_super_call);
Diag(InitMethod->getLocation(),
diag::note_objc_designated_init_marked_here);
}
getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
}
if (getCurFunction()->ObjCWarnForNoInitDelegation) {
// Don't issue this warning for unavaialable inits.
if (!MD->isUnavailable())
Diag(MD->getLocation(),
diag::warn_objc_secondary_init_missing_init_call);
getCurFunction()->ObjCWarnForNoInitDelegation = false;
}
} else {
return nullptr;
}
assert(!getCurFunction()->ObjCShouldCallSuper &&
"This should only be set for ObjC methods, which should have been "
"handled in the block above.");
// Verify and clean out per-function state.
if (Body && (!FD || !FD->isDefaulted())) {
// C++ constructors that have function-try-blocks can't have return
// statements in the handlers of that block. (C++ [except.handle]p14)
// Verify this.
if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
// Verify that gotos and switch cases don't jump into scopes illegally.
if (getCurFunction()->NeedsScopeChecking() &&
!PP.isCodeCompletionEnabled())
DiagnoseInvalidJumps(Body);
if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
if (!Destructor->getParent()->isDependentType())
CheckDestructor(Destructor);
MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
Destructor->getParent());
}
// If any errors have occurred, clear out any temporaries that may have
// been leftover. This ensures that these temporaries won't be picked up for
// deletion in some later function.
if (getDiagnostics().hasErrorOccurred() ||
getDiagnostics().getSuppressAllDiagnostics()) {
DiscardCleanupsInEvaluationContext();
}
if (!getDiagnostics().hasUncompilableErrorOccurred() &&
!isa<FunctionTemplateDecl>(dcl)) {
// Since the body is valid, issue any analysis-based warnings that are
// enabled.
ActivePolicy = &WP;
}
if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
(!CheckConstexprFunctionDecl(FD) ||
!CheckConstexprFunctionBody(FD, Body)))
FD->setInvalidDecl();
if (FD && FD->hasAttr<NakedAttr>()) {
for (const Stmt *S : Body->children()) {
if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
Diag(S->getLocStart(), diag::err_non_asm_stmt_in_naked_function);
Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
FD->setInvalidDecl();
break;
}
}
}
assert(ExprCleanupObjects.size() ==
ExprEvalContexts.back().NumCleanupObjects &&
"Leftover temporaries in function");
assert(!ExprNeedsCleanups && "Unaccounted cleanups in function");
assert(MaybeODRUseExprs.empty() &&
"Leftover expressions for odr-use checking");
}
if (!IsInstantiation)
PopDeclContext();
PopFunctionScopeInfo(ActivePolicy, dcl);
// If any errors have occurred, clear out any temporaries that may have
// been leftover. This ensures that these temporaries won't be picked up for
// deletion in some later function.
if (getDiagnostics().hasErrorOccurred()) {
DiscardCleanupsInEvaluationContext();
}
return dcl;
}
/// When we finish delayed parsing of an attribute, we must attach it to the
/// relevant Decl.
void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
ParsedAttributes &Attrs) {
// Always attach attributes to the underlying decl.
if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
D = TD->getTemplatedDecl();
ProcessDeclAttributeList(S, D, Attrs.getList());
if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
if (Method->isStatic())
checkThisInStaticMemberFunctionAttributes(Method);
}
/// ImplicitlyDefineFunction - An undeclared identifier was used in a function
/// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
IdentifierInfo &II, Scope *S) {
// Before we produce a declaration for an implicitly defined
// function, see whether there was a locally-scoped declaration of
// this name as a function or variable. If so, use that
// (non-visible) declaration, and complain about it.
if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) {
Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev;
Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
return ExternCPrev;
}
// Extension in C99. Legal in C90, but warn about it.
unsigned diag_id;
if (II.getName().startswith("__builtin_"))
diag_id = diag::warn_builtin_unknown;
else if (getLangOpts().C99)
diag_id = diag::ext_implicit_function_decl;
else
diag_id = diag::warn_implicit_function_decl;
Diag(Loc, diag_id) << &II;
// Because typo correction is expensive, only do it if the implicit
// function declaration is going to be treated as an error.
if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
TypoCorrection Corrected;
if (S &&
(Corrected = CorrectTypo(
DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, nullptr,
llvm::make_unique<DeclFilterCCC<FunctionDecl>>(), CTK_NonError)))
diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
/*ErrorRecovery*/false);
}
// Set a Declarator for the implicit definition: int foo();
const char *Dummy;
AttributeFactory attrFactory;
DeclSpec DS(attrFactory);
unsigned DiagID;
bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
Context.getPrintingPolicy());
(void)Error; // Silence warning.
assert(!Error && "Error setting up implicit decl!");
SourceLocation NoLoc;
Declarator D(DS, Declarator::BlockContext);
D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
/*IsAmbiguous=*/false,
/*LParenLoc=*/NoLoc,
/*Params=*/nullptr,
/*NumParams=*/0,
/*EllipsisLoc=*/NoLoc,
/*RParenLoc=*/NoLoc,
/*TypeQuals=*/0,
/*RefQualifierIsLvalueRef=*/true,
/*RefQualifierLoc=*/NoLoc,
/*ConstQualifierLoc=*/NoLoc,
/*VolatileQualifierLoc=*/NoLoc,
/*RestrictQualifierLoc=*/NoLoc,
/*MutableLoc=*/NoLoc,
EST_None,
/*ESpecRange=*/SourceRange(),
/*Exceptions=*/nullptr,
/*ExceptionRanges=*/nullptr,
/*NumExceptions=*/0,
/*NoexceptExpr=*/nullptr,
/*ExceptionSpecTokens=*/nullptr,
Loc, Loc, D),
DS.getAttributes(),
SourceLocation());
D.SetIdentifier(&II, Loc);
// Insert this function into translation-unit scope.
DeclContext *PrevDC = CurContext;
CurContext = Context.getTranslationUnitDecl();
FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
FD->setImplicit();
CurContext = PrevDC;
AddKnownFunctionAttributes(FD);
return FD;
}
/// \brief Adds any function attributes that we know a priori based on
/// the declaration of this function.
///
/// These attributes can apply both to implicitly-declared builtins
/// (like __builtin___printf_chk) or to library-declared functions
/// like NSLog or printf.
///
/// We need to check for duplicate attributes both here and where user-written
/// attributes are applied to declarations.
void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
if (FD->isInvalidDecl())
return;
// If this is a built-in function, map its builtin attributes to
// actual attributes.
if (unsigned BuiltinID = FD->getBuiltinID()) {
// Handle printf-formatting attributes.
unsigned FormatIdx;
bool HasVAListArg;
if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
if (!FD->hasAttr<FormatAttr>()) {
const char *fmt = "printf";
unsigned int NumParams = FD->getNumParams();
if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
fmt = "NSString";
FD->addAttr(FormatAttr::CreateImplicit(Context,
&Context.Idents.get(fmt),
FormatIdx+1,
HasVAListArg ? 0 : FormatIdx+2,
FD->getLocation()));
}
}
if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
HasVAListArg)) {
if (!FD->hasAttr<FormatAttr>())
FD->addAttr(FormatAttr::CreateImplicit(Context,
&Context.Idents.get("scanf"),
FormatIdx+1,
HasVAListArg ? 0 : FormatIdx+2,
FD->getLocation()));
}
// Mark const if we don't care about errno and that is the only
// thing preventing the function from being const. This allows
// IRgen to use LLVM intrinsics for such functions.
if (!getLangOpts().MathErrno &&
Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) {
if (!FD->hasAttr<ConstAttr>())
FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
}
if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
!FD->hasAttr<ReturnsTwiceAttr>())
FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
FD->getLocation()));
if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
if (getLangOpts().CUDA && getLangOpts().CUDATargetOverloads &&
Context.BuiltinInfo.isTSBuiltin(BuiltinID) &&
!FD->hasAttr<CUDADeviceAttr>() && !FD->hasAttr<CUDAHostAttr>()) {
// Assign appropriate attribute depending on CUDA compilation
// mode and the target builtin belongs to. E.g. during host
// compilation, aux builtins are __device__, the rest are __host__.
if (getLangOpts().CUDAIsDevice !=
Context.BuiltinInfo.isAuxBuiltinID(BuiltinID))
FD->addAttr(CUDADeviceAttr::CreateImplicit(Context, FD->getLocation()));
else
FD->addAttr(CUDAHostAttr::CreateImplicit(Context, FD->getLocation()));
}
}
IdentifierInfo *Name = FD->getIdentifier();
if (!Name)
return;
if ((!getLangOpts().CPlusPlus &&
FD->getDeclContext()->isTranslationUnit()) ||
(isa<LinkageSpecDecl>(FD->getDeclContext()) &&
cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
LinkageSpecDecl::lang_c)) {
// Okay: this could be a libc/libm/Objective-C function we know
// about.
} else
return;
if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
// FIXME: asprintf and vasprintf aren't C99 functions. Should they be
// target-specific builtins, perhaps?
if (!FD->hasAttr<FormatAttr>())
FD->addAttr(FormatAttr::CreateImplicit(Context,
&Context.Idents.get("printf"), 2,
Name->isStr("vasprintf") ? 0 : 3,
FD->getLocation()));
}
if (Name->isStr("__CFStringMakeConstantString")) {
// We already have a __builtin___CFStringMakeConstantString,
// but builds that use -fno-constant-cfstrings don't go through that.
if (!FD->hasAttr<FormatArgAttr>())
FD->addAttr(FormatArgAttr::CreateImplicit(Context, 1,
FD->getLocation()));
}
}
TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
TypeSourceInfo *TInfo) {
assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
if (!TInfo) {
assert(D.isInvalidType() && "no declarator info for valid type");
TInfo = Context.getTrivialTypeSourceInfo(T);
}
// Scope manipulation handled by caller.
TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
D.getLocStart(),
D.getIdentifierLoc(),
D.getIdentifier(),
TInfo);
// Bail out immediately if we have an invalid declaration.
if (D.isInvalidType()) {
NewTD->setInvalidDecl();
return NewTD;
}
if (D.getDeclSpec().isModulePrivateSpecified()) {
if (CurContext->isFunctionOrMethod())
Diag(NewTD->getLocation(), diag::err_module_private_local)
<< 2 << NewTD->getDeclName()
<< SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
<< FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
else
NewTD->setModulePrivate();
}
// C++ [dcl.typedef]p8:
// If the typedef declaration defines an unnamed class (or
// enum), the first typedef-name declared by the declaration
// to be that class type (or enum type) is used to denote the
// class type (or enum type) for linkage purposes only.
// We need to check whether the type was declared in the declaration.
switch (D.getDeclSpec().getTypeSpecType()) {
case TST_enum:
case TST_struct:
case TST_interface:
case TST_union:
case TST_class: {
TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
setTagNameForLinkagePurposes(tagFromDeclSpec, NewTD);
break;
}
default:
break;
}
return NewTD;
}
/// \brief Check that this is a valid underlying type for an enum declaration.
bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
QualType T = TI->getType();
if (T->isDependentType())
return false;
if (const BuiltinType *BT = T->getAs<BuiltinType>())
if (BT->isInteger())
return false;
Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
return true;
}
/// Check whether this is a valid redeclaration of a previous enumeration.
/// \return true if the redeclaration was invalid.
bool Sema::CheckEnumRedeclaration(
SourceLocation EnumLoc, bool IsScoped, QualType EnumUnderlyingTy,
bool EnumUnderlyingIsImplicit, const EnumDecl *Prev) {
bool IsFixed = !EnumUnderlyingTy.isNull();
if (IsScoped != Prev->isScoped()) {
Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
<< Prev->isScoped();
Diag(Prev->getLocation(), diag::note_previous_declaration);
return true;
}
if (IsFixed && Prev->isFixed()) {
if (!EnumUnderlyingTy->isDependentType() &&
!Prev->getIntegerType()->isDependentType() &&
!Context.hasSameUnqualifiedType(EnumUnderlyingTy,
Prev->getIntegerType())) {
// TODO: Highlight the underlying type of the redeclaration.
Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
<< EnumUnderlyingTy << Prev->getIntegerType();
Diag(Prev->getLocation(), diag::note_previous_declaration)
<< Prev->getIntegerTypeRange();
return true;
}
} else if (IsFixed && !Prev->isFixed() && EnumUnderlyingIsImplicit) {
;
} else if (!IsFixed && Prev->isFixed() && !Prev->getIntegerTypeSourceInfo()) {
;
} else if (IsFixed != Prev->isFixed()) {
Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
<< Prev->isFixed();
Diag(Prev->getLocation(), diag::note_previous_declaration);
return true;
}
return false;
}
/// \brief Get diagnostic %select index for tag kind for
/// redeclaration diagnostic message.
/// WARNING: Indexes apply to particular diagnostics only!
///
/// \returns diagnostic %select index.
static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
switch (Tag) {
case TTK_Struct: return 0;
case TTK_Interface: return 1;
case TTK_Class: return 2;
default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
}
}
/// \brief Determine if tag kind is a class-key compatible with
/// class for redeclaration (class, struct, or __interface).
///
/// \returns true iff the tag kind is compatible.
static bool isClassCompatTagKind(TagTypeKind Tag)
{
return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
}
/// \brief Determine whether a tag with a given kind is acceptable
/// as a redeclaration of the given tag declaration.
///
/// \returns true if the new tag kind is acceptable, false otherwise.
bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
TagTypeKind NewTag, bool isDefinition,
SourceLocation NewTagLoc,
const IdentifierInfo *Name) {
// C++ [dcl.type.elab]p3:
// The class-key or enum keyword present in the
// elaborated-type-specifier shall agree in kind with the
// declaration to which the name in the elaborated-type-specifier
// refers. This rule also applies to the form of
// elaborated-type-specifier that declares a class-name or
// friend class since it can be construed as referring to the
// definition of the class. Thus, in any
// elaborated-type-specifier, the enum keyword shall be used to
// refer to an enumeration (7.2), the union class-key shall be
// used to refer to a union (clause 9), and either the class or
// struct class-key shall be used to refer to a class (clause 9)
// declared using the class or struct class-key.
TagTypeKind OldTag = Previous->getTagKind();
if (!isDefinition || !isClassCompatTagKind(NewTag))
if (OldTag == NewTag)
return true;
if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) {
// Warn about the struct/class tag mismatch.
bool isTemplate = false;
if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
isTemplate = Record->getDescribedClassTemplate();
if (!ActiveTemplateInstantiations.empty()) {
// In a template instantiation, do not offer fix-its for tag mismatches
// since they usually mess up the template instead of fixing the problem.
Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
<< getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
<< getRedeclDiagFromTagKind(OldTag);
return true;
}
if (isDefinition) {
// On definitions, check previous tags and issue a fix-it for each
// one that doesn't match the current tag.
if (Previous->getDefinition()) {
// Don't suggest fix-its for redefinitions.
return true;
}
bool previousMismatch = false;
for (auto I : Previous->redecls()) {
if (I->getTagKind() != NewTag) {
if (!previousMismatch) {
previousMismatch = true;
Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
<< getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
<< getRedeclDiagFromTagKind(I->getTagKind());
}
Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
<< getRedeclDiagFromTagKind(NewTag)
<< FixItHint::CreateReplacement(I->getInnerLocStart(),
TypeWithKeyword::getTagTypeKindName(NewTag));
}
}
return true;
}
// Check for a previous definition. If current tag and definition
// are same type, do nothing. If no definition, but disagree with
// with previous tag type, give a warning, but no fix-it.
const TagDecl *Redecl = Previous->getDefinition() ?
Previous->getDefinition() : Previous;
if (Redecl->getTagKind() == NewTag) {
return true;
}
Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
<< getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
<< getRedeclDiagFromTagKind(OldTag);
Diag(Redecl->getLocation(), diag::note_previous_use);
// If there is a previous definition, suggest a fix-it.
if (Previous->getDefinition()) {
Diag(NewTagLoc, diag::note_struct_class_suggestion)
<< getRedeclDiagFromTagKind(Redecl->getTagKind())
<< FixItHint::CreateReplacement(SourceRange(NewTagLoc),
TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
}
return true;
}
return false;
}
/// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
/// from an outer enclosing namespace or file scope inside a friend declaration.
/// This should provide the commented out code in the following snippet:
/// namespace N {
/// struct X;
/// namespace M {
/// struct Y { friend struct /*N::*/ X; };
/// }
/// }
static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
SourceLocation NameLoc) {
// While the decl is in a namespace, do repeated lookup of that name and see
// if we get the same namespace back. If we do not, continue until
// translation unit scope, at which point we have a fully qualified NNS.
SmallVector<IdentifierInfo *, 4> Namespaces;
DeclContext *DC = ND->getDeclContext()->getRedeclContext();
for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
// This tag should be declared in a namespace, which can only be enclosed by
// other namespaces. Bail if there's an anonymous namespace in the chain.
NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
if (!Namespace || Namespace->isAnonymousNamespace())
return FixItHint();
IdentifierInfo *II = Namespace->getIdentifier();
Namespaces.push_back(II);
NamedDecl *Lookup = SemaRef.LookupSingleName(
S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
if (Lookup == Namespace)
break;
}
// Once we have all the namespaces, reverse them to go outermost first, and
// build an NNS.
SmallString<64> Insertion;
llvm::raw_svector_ostream OS(Insertion);
if (DC->isTranslationUnit())
OS << "::";
std::reverse(Namespaces.begin(), Namespaces.end());
for (auto *II : Namespaces)
OS << II->getName() << "::";
return FixItHint::CreateInsertion(NameLoc, Insertion);
}
/// \brief Determine whether a tag originally declared in context \p OldDC can
/// be redeclared with an unqualfied name in \p NewDC (assuming name lookup
/// found a declaration in \p OldDC as a previous decl, perhaps through a
/// using-declaration).
static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
DeclContext *NewDC) {
OldDC = OldDC->getRedeclContext();
NewDC = NewDC->getRedeclContext();
if (OldDC->Equals(NewDC))
return true;
// In MSVC mode, we allow a redeclaration if the contexts are related (either
// encloses the other).
if (S.getLangOpts().MSVCCompat &&
(OldDC->Encloses(NewDC) || NewDC->Encloses(OldDC)))
return true;
return false;
}
/// \brief This is invoked when we see 'struct foo' or 'struct {'. In the
/// former case, Name will be non-null. In the later case, Name will be null.
/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
/// reference/declaration/definition of a tag.
///
/// \param IsTypeSpecifier \c true if this is a type-specifier (or
/// trailing-type-specifier) other than one in an alias-declaration.
///
/// \param SkipBody If non-null, will be set to indicate if the caller should
/// skip the definition of this tag and treat it as if it were a declaration.
Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
SourceLocation KWLoc, CXXScopeSpec &SS,
IdentifierInfo *Name, SourceLocation NameLoc,
AttributeList *Attr, AccessSpecifier AS,
SourceLocation ModulePrivateLoc,
MultiTemplateParamsArg TemplateParameterLists,
bool &OwnedDecl, bool &IsDependent,
SourceLocation ScopedEnumKWLoc,
bool ScopedEnumUsesClassTag,
TypeResult UnderlyingType,
bool IsTypeSpecifier, SkipBodyInfo *SkipBody) {
// If this is not a definition, it must have a name.
IdentifierInfo *OrigName = Name;
assert((Name != nullptr || TUK == TUK_Definition) &&
"Nameless record must be a definition!");
assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
OwnedDecl = false;
TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
bool ScopedEnum = ScopedEnumKWLoc.isValid();
// FIXME: Check explicit specializations more carefully.
bool isExplicitSpecialization = false;
bool Invalid = false;
// We only need to do this matching if we have template parameters
// or a scope specifier, which also conveniently avoids this work
// for non-C++ cases.
if (TemplateParameterLists.size() > 0 ||
(SS.isNotEmpty() && TUK != TUK_Reference)) {
if (TemplateParameterList *TemplateParams =
MatchTemplateParametersToScopeSpecifier(
KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
TUK == TUK_Friend, isExplicitSpecialization, Invalid)) {
if (Kind == TTK_Enum) {
Diag(KWLoc, diag::err_enum_template);
return nullptr;
}
if (TemplateParams->size() > 0) {
// This is a declaration or definition of a class template (which may
// be a member of another template).
if (Invalid)
return nullptr;
OwnedDecl = false;
DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc,
SS, Name, NameLoc, Attr,
TemplateParams, AS,
ModulePrivateLoc,
/*FriendLoc*/SourceLocation(),
TemplateParameterLists.size()-1,
TemplateParameterLists.data(),
SkipBody);
return Result.get();
} else {
// The "template<>" header is extraneous.
Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
<< TypeWithKeyword::getTagTypeKindName(Kind) << Name;
isExplicitSpecialization = true;
}
}
}
// Figure out the underlying type if this a enum declaration. We need to do
// this early, because it's needed to detect if this is an incompatible
// redeclaration.
llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
bool EnumUnderlyingIsImplicit = false;
if (Kind == TTK_Enum) {
if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum))
// No underlying type explicitly specified, or we failed to parse the
// type, default to int.
EnumUnderlying = Context.IntTy.getTypePtr();
else if (UnderlyingType.get()) {
// C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
// integral type; any cv-qualification is ignored.
TypeSourceInfo *TI = nullptr;
GetTypeFromParser(UnderlyingType.get(), &TI);
EnumUnderlying = TI;
if (CheckEnumUnderlyingType(TI))
// Recover by falling back to int.
EnumUnderlying = Context.IntTy.getTypePtr();
if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
UPPC_FixedUnderlyingType))
EnumUnderlying = Context.IntTy.getTypePtr();
} else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
if (getLangOpts().MSVCCompat || TUK == TUK_Definition) {
// Microsoft enums are always of int type.
EnumUnderlying = Context.IntTy.getTypePtr();
EnumUnderlyingIsImplicit = true;
}
}
}
DeclContext *SearchDC = CurContext;
DeclContext *DC = CurContext;
bool isStdBadAlloc = false;
RedeclarationKind Redecl = ForRedeclaration;
if (TUK == TUK_Friend || TUK == TUK_Reference)
Redecl = NotForRedeclaration;
LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
if (Name && SS.isNotEmpty()) {
// We have a nested-name tag ('struct foo::bar').
// Check for invalid 'foo::'.
if (SS.isInvalid()) {
Name = nullptr;
goto CreateNewDecl;
}
// If this is a friend or a reference to a class in a dependent
// context, don't try to make a decl for it.
if (TUK == TUK_Friend || TUK == TUK_Reference) {
DC = computeDeclContext(SS, false);
if (!DC) {
IsDependent = true;
return nullptr;
}
} else {
DC = computeDeclContext(SS, true);
if (!DC) {
Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
<< SS.getRange();
return nullptr;
}
}
if (RequireCompleteDeclContext(SS, DC))
return nullptr;
SearchDC = DC;
// Look-up name inside 'foo::'.
LookupQualifiedName(Previous, DC);
if (Previous.isAmbiguous())
return nullptr;
if (Previous.empty()) {
// Name lookup did not find anything. However, if the
// nested-name-specifier refers to the current instantiation,
// and that current instantiation has any dependent base
// classes, we might find something at instantiation time: treat
// this as a dependent elaborated-type-specifier.
// But this only makes any sense for reference-like lookups.
if (Previous.wasNotFoundInCurrentInstantiation() &&
(TUK == TUK_Reference || TUK == TUK_Friend)) {
IsDependent = true;
return nullptr;
}
// A tag 'foo::bar' must already exist.
Diag(NameLoc, diag::err_not_tag_in_scope)
<< Kind << Name << DC << SS.getRange();
Name = nullptr;
Invalid = true;
goto CreateNewDecl;
}
} else if (Name) {
// C++14 [class.mem]p14:
// If T is the name of a class, then each of the following shall have a
// name different from T:
// -- every member of class T that is itself a type
if (TUK != TUK_Reference && TUK != TUK_Friend &&
DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
return nullptr;
// If this is a named struct, check to see if there was a previous forward
// declaration or definition.
// FIXME: We're looking into outer scopes here, even when we
// shouldn't be. Doing so can result in ambiguities that we
// shouldn't be diagnosing.
LookupName(Previous, S);
// When declaring or defining a tag, ignore ambiguities introduced
// by types using'ed into this scope.
if (Previous.isAmbiguous() &&
(TUK == TUK_Definition || TUK == TUK_Declaration)) {
LookupResult::Filter F = Previous.makeFilter();
while (F.hasNext()) {
NamedDecl *ND = F.next();
if (ND->getDeclContext()->getRedeclContext() != SearchDC)
F.erase();
}
F.done();
}
// C++11 [namespace.memdef]p3:
// If the name in a friend declaration is neither qualified nor
// a template-id and the declaration is a function or an
// elaborated-type-specifier, the lookup to determine whether
// the entity has been previously declared shall not consider
// any scopes outside the innermost enclosing namespace.
//
// MSVC doesn't implement the above rule for types, so a friend tag
// declaration may be a redeclaration of a type declared in an enclosing
// scope. They do implement this rule for friend functions.
//
// Does it matter that this should be by scope instead of by
// semantic context?
if (!Previous.empty() && TUK == TUK_Friend) {
DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
LookupResult::Filter F = Previous.makeFilter();
bool FriendSawTagOutsideEnclosingNamespace = false;
while (F.hasNext()) {
NamedDecl *ND = F.next();
DeclContext *DC = ND->getDeclContext()->getRedeclContext();
if (DC->isFileContext() &&
!EnclosingNS->Encloses(ND->getDeclContext())) {
if (getLangOpts().MSVCCompat)
FriendSawTagOutsideEnclosingNamespace = true;
else
F.erase();
}
}
F.done();
// Diagnose this MSVC extension in the easy case where lookup would have
// unambiguously found something outside the enclosing namespace.
if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
NamedDecl *ND = Previous.getFoundDecl();
Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
<< createFriendTagNNSFixIt(*this, ND, S, NameLoc);
}
}
// Note: there used to be some attempt at recovery here.
if (Previous.isAmbiguous())
return nullptr;
if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
// FIXME: This makes sure that we ignore the contexts associated
// with C structs, unions, and enums when looking for a matching
// tag declaration or definition. See the similar lookup tweak
// in Sema::LookupName; is there a better way to deal with this?
while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
SearchDC = SearchDC->getParent();
}
}
if (Previous.isSingleResult() &&
Previous.getFoundDecl()->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
// Just pretend that we didn't see the previous declaration.
Previous.clear();
}
if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) {
// This is a declaration of or a reference to "std::bad_alloc".
isStdBadAlloc = true;
if (Previous.empty() && StdBadAlloc) {
// std::bad_alloc has been implicitly declared (but made invisible to
// name lookup). Fill in this implicit declaration as the previous
// declaration, so that the declarations get chained appropriately.
Previous.addDecl(getStdBadAlloc());
}
}
// If we didn't find a previous declaration, and this is a reference
// (or friend reference), move to the correct scope. In C++, we
// also need to do a redeclaration lookup there, just in case
// there's a shadow friend decl.
if (Name && Previous.empty() &&
(TUK == TUK_Reference || TUK == TUK_Friend)) {
if (Invalid) goto CreateNewDecl;
assert(SS.isEmpty());
if (TUK == TUK_Reference) {
// C++ [basic.scope.pdecl]p5:
// -- for an elaborated-type-specifier of the form
//
// class-key identifier
//
// if the elaborated-type-specifier is used in the
// decl-specifier-seq or parameter-declaration-clause of a
// function defined in namespace scope, the identifier is
// declared as a class-name in the namespace that contains
// the declaration; otherwise, except as a friend
// declaration, the identifier is declared in the smallest
// non-class, non-function-prototype scope that contains the
// declaration.
//
// C99 6.7.2.3p8 has a similar (but not identical!) provision for
// C structs and unions.
//
// It is an error in C++ to declare (rather than define) an enum
// type, including via an elaborated type specifier. We'll
// diagnose that later; for now, declare the enum in the same
// scope as we would have picked for any other tag type.
//
// GNU C also supports this behavior as part of its incomplete
// enum types extension, while GNU C++ does not.
//
// Find the context where we'll be declaring the tag.
// FIXME: We would like to maintain the current DeclContext as the
// lexical context,
while (!SearchDC->isFileContext() && !SearchDC->isFunctionOrMethod())
SearchDC = SearchDC->getParent();
// Find the scope where we'll be declaring the tag.
while (S->isClassScope() ||
(getLangOpts().CPlusPlus &&
S->isFunctionPrototypeScope()) ||
((S->getFlags() & Scope::DeclScope) == 0) ||
(S->getEntity() && S->getEntity()->isTransparentContext()))
S = S->getParent();
} else {
assert(TUK == TUK_Friend);
// C++ [namespace.memdef]p3:
// If a friend declaration in a non-local class first declares a
// class or function, the friend class or function is a member of
// the innermost enclosing namespace.
SearchDC = SearchDC->getEnclosingNamespaceContext();
}
// In C++, we need to do a redeclaration lookup to properly
// diagnose some problems.
// FIXME: redeclaration lookup is also used (with and without C++) to find a
// hidden declaration so that we don't get ambiguity errors when using a
// type declared by an elaborated-type-specifier. In C that is not correct
// and we should instead merge compatible types found by lookup.
if (getLangOpts().CPlusPlus) {
Previous.setRedeclarationKind(ForRedeclaration);
LookupQualifiedName(Previous, SearchDC);
} else {
Previous.setRedeclarationKind(ForRedeclaration);
LookupName(Previous, S);
}
}
// If we have a known previous declaration to use, then use it.
if (Previous.empty() && SkipBody && SkipBody->Previous)
Previous.addDecl(SkipBody->Previous);
if (!Previous.empty()) {
NamedDecl *PrevDecl = Previous.getFoundDecl();
NamedDecl *DirectPrevDecl = Previous.getRepresentativeDecl();
// It's okay to have a tag decl in the same scope as a typedef
// which hides a tag decl in the same scope. Finding this
// insanity with a redeclaration lookup can only actually happen
// in C++.
//
// This is also okay for elaborated-type-specifiers, which is
// technically forbidden by the current standard but which is
// okay according to the likely resolution of an open issue;
// see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
if (getLangOpts().CPlusPlus) {
if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
TagDecl *Tag = TT->getDecl();
if (Tag->getDeclName() == Name &&
Tag->getDeclContext()->getRedeclContext()
->Equals(TD->getDeclContext()->getRedeclContext())) {
PrevDecl = Tag;
Previous.clear();
Previous.addDecl(Tag);
Previous.resolveKind();
}
}
}
}
// If this is a redeclaration of a using shadow declaration, it must
// declare a tag in the same context. In MSVC mode, we allow a
// redefinition if either context is within the other.
if (auto *Shadow = dyn_cast<UsingShadowDecl>(DirectPrevDecl)) {
auto *OldTag = dyn_cast<TagDecl>(PrevDecl);
if (SS.isEmpty() && TUK != TUK_Reference && TUK != TUK_Friend &&
isDeclInScope(Shadow, SearchDC, S, isExplicitSpecialization) &&
!(OldTag && isAcceptableTagRedeclContext(
*this, OldTag->getDeclContext(), SearchDC))) {
Diag(KWLoc, diag::err_using_decl_conflict_reverse);
Diag(Shadow->getTargetDecl()->getLocation(),
diag::note_using_decl_target);
Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl)
<< 0;
// Recover by ignoring the old declaration.
Previous.clear();
goto CreateNewDecl;
}
}
if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
// If this is a use of a previous tag, or if the tag is already declared
// in the same scope (so that the definition/declaration completes or
// rementions the tag), reuse the decl.
if (TUK == TUK_Reference || TUK == TUK_Friend ||
isDeclInScope(DirectPrevDecl, SearchDC, S,
SS.isNotEmpty() || isExplicitSpecialization)) {
// Make sure that this wasn't declared as an enum and now used as a
// struct or something similar.
if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
TUK == TUK_Definition, KWLoc,
Name)) {
bool SafeToContinue
= (PrevTagDecl->getTagKind() != TTK_Enum &&
Kind != TTK_Enum);
if (SafeToContinue)
Diag(KWLoc, diag::err_use_with_wrong_tag)
<< Name
<< FixItHint::CreateReplacement(SourceRange(KWLoc),
PrevTagDecl->getKindName());
else
Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
if (SafeToContinue)
Kind = PrevTagDecl->getTagKind();
else {
// Recover by making this an anonymous redefinition.
Name = nullptr;
Previous.clear();
Invalid = true;
}
}
if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
// If this is an elaborated-type-specifier for a scoped enumeration,
// the 'class' keyword is not necessary and not permitted.
if (TUK == TUK_Reference || TUK == TUK_Friend) {
if (ScopedEnum)
Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
<< PrevEnum->isScoped()
<< FixItHint::CreateRemoval(ScopedEnumKWLoc);
return PrevTagDecl;
}
QualType EnumUnderlyingTy;
if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
EnumUnderlyingTy = TI->getType().getUnqualifiedType();
else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
EnumUnderlyingTy = QualType(T, 0);
// All conflicts with previous declarations are recovered by
// returning the previous declaration, unless this is a definition,
// in which case we want the caller to bail out.
if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
ScopedEnum, EnumUnderlyingTy,
EnumUnderlyingIsImplicit, PrevEnum))
return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
}
// C++11 [class.mem]p1:
// A member shall not be declared twice in the member-specification,
// except that a nested class or member class template can be declared
// and then later defined.
if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
S->isDeclScope(PrevDecl)) {
Diag(NameLoc, diag::ext_member_redeclared);
Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
}
if (!Invalid) {
// If this is a use, just return the declaration we found, unless
// we have attributes.
// FIXME: In the future, return a variant or some other clue
// for the consumer of this Decl to know it doesn't own it.
// For our current ASTs this shouldn't be a problem, but will
// need to be changed with DeclGroups.
if (!Attr &&
((TUK == TUK_Reference &&
(!PrevTagDecl->getFriendObjectKind() || getLangOpts().MicrosoftExt))
|| TUK == TUK_Friend))
return PrevTagDecl;
// Diagnose attempts to redefine a tag.
if (TUK == TUK_Definition) {
if (NamedDecl *Def = PrevTagDecl->getDefinition()) {
// If we're defining a specialization and the previous definition
// is from an implicit instantiation, don't emit an error
// here; we'll catch this in the general case below.
bool IsExplicitSpecializationAfterInstantiation = false;
if (isExplicitSpecialization) {
if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
IsExplicitSpecializationAfterInstantiation =
RD->getTemplateSpecializationKind() !=
TSK_ExplicitSpecialization;
else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
IsExplicitSpecializationAfterInstantiation =
ED->getTemplateSpecializationKind() !=
TSK_ExplicitSpecialization;
}
NamedDecl *Hidden = nullptr;
if (SkipBody && getLangOpts().CPlusPlus &&
!hasVisibleDefinition(Def, &Hidden)) {
// There is a definition of this tag, but it is not visible. We
// explicitly make use of C++'s one definition rule here, and
// assume that this definition is identical to the hidden one
// we already have. Make the existing definition visible and
// use it in place of this one.
SkipBody->ShouldSkip = true;
makeMergedDefinitionVisible(Hidden, KWLoc);
return Def;
} else if (!IsExplicitSpecializationAfterInstantiation) {
// A redeclaration in function prototype scope in C isn't
// visible elsewhere, so merely issue a warning.
if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
else
Diag(NameLoc, diag::err_redefinition) << Name;
Diag(Def->getLocation(), diag::note_previous_definition);
// If this is a redefinition, recover by making this
// struct be anonymous, which will make any later
// references get the previous definition.
Name = nullptr;
Previous.clear();
Invalid = true;
}
} else {
// If the type is currently being defined, complain
// about a nested redefinition.
auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
if (TD->isBeingDefined()) {
Diag(NameLoc, diag::err_nested_redefinition) << Name;
Diag(PrevTagDecl->getLocation(),
diag::note_previous_definition);
Name = nullptr;
Previous.clear();
Invalid = true;
}
}
// Okay, this is definition of a previously declared or referenced
// tag. We're going to create a new Decl for it.
}
// Okay, we're going to make a redeclaration. If this is some kind
// of reference, make sure we build the redeclaration in the same DC
// as the original, and ignore the current access specifier.
if (TUK == TUK_Friend || TUK == TUK_Reference) {
SearchDC = PrevTagDecl->getDeclContext();
AS = AS_none;
}
}
// If we get here we have (another) forward declaration or we
// have a definition. Just create a new decl.
} else {
// If we get here, this is a definition of a new tag type in a nested
// scope, e.g. "struct foo; void bar() { struct foo; }", just create a
// new decl/type. We set PrevDecl to NULL so that the entities
// have distinct types.
Previous.clear();
}
// If we get here, we're going to create a new Decl. If PrevDecl
// is non-NULL, it's a definition of the tag declared by
// PrevDecl. If it's NULL, we have a new definition.
// Otherwise, PrevDecl is not a tag, but was found with tag
// lookup. This is only actually possible in C++, where a few
// things like templates still live in the tag namespace.
} else {
// Use a better diagnostic if an elaborated-type-specifier
// found the wrong kind of type on the first
// (non-redeclaration) lookup.
if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
!Previous.isForRedeclaration()) {
unsigned Kind = 0;
if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind;
Diag(PrevDecl->getLocation(), diag::note_declared_at);
Invalid = true;
// Otherwise, only diagnose if the declaration is in scope.
} else if (!isDeclInScope(DirectPrevDecl, SearchDC, S,
SS.isNotEmpty() || isExplicitSpecialization)) {
// do nothing
// Diagnose implicit declarations introduced by elaborated types.
} else if (TUK == TUK_Reference || TUK == TUK_Friend) {
unsigned Kind = 0;
if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
Diag(NameLoc, diag::err_tag_reference_conflict) << Kind;
Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
Invalid = true;
// Otherwise it's a declaration. Call out a particularly common
// case here.
} else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
unsigned Kind = 0;
if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
Diag(NameLoc, diag::err_tag_definition_of_typedef)
<< Name << Kind << TND->getUnderlyingType();
Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
Invalid = true;
// Otherwise, diagnose.
} else {
// The tag name clashes with something else in the target scope,
// issue an error and recover by making this tag be anonymous.
Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
Diag(PrevDecl->getLocation(), diag::note_previous_definition);
Name = nullptr;
Invalid = true;
}
// The existing declaration isn't relevant to us; we're in a
// new scope, so clear out the previous declaration.
Previous.clear();
}
}
CreateNewDecl:
TagDecl *PrevDecl = nullptr;
if (Previous.isSingleResult())
PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
// If there is an identifier, use the location of the identifier as the
// location of the decl, otherwise use the location of the struct/union
// keyword.
SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
// Otherwise, create a new declaration. If there is a previous
// declaration of the same entity, the two will be linked via
// PrevDecl.
TagDecl *New;
bool IsForwardReference = false;
if (Kind == TTK_Enum) {
// FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
// enum X { A, B, C } D; D should chain to X.
New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
ScopedEnumUsesClassTag, !EnumUnderlying.isNull());
// If this is an undefined enum, warn.
if (TUK != TUK_Definition && !Invalid) {
TagDecl *Def;
if ((getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) &&
cast<EnumDecl>(New)->isFixed()) {
// C++0x: 7.2p2: opaque-enum-declaration.
// Conflicts are diagnosed above. Do nothing.
}
else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
Diag(Loc, diag::ext_forward_ref_enum_def)
<< New;
Diag(Def->getLocation(), diag::note_previous_definition);
} else {
unsigned DiagID = diag::ext_forward_ref_enum;
if (getLangOpts().MSVCCompat)
DiagID = diag::ext_ms_forward_ref_enum;
else if (getLangOpts().CPlusPlus)
DiagID = diag::err_forward_ref_enum;
Diag(Loc, DiagID);
// If this is a forward-declared reference to an enumeration, make a
// note of it; we won't actually be introducing the declaration into
// the declaration context.
if (TUK == TUK_Reference)
IsForwardReference = true;
}
}
if (EnumUnderlying) {
EnumDecl *ED = cast<EnumDecl>(New);
if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
ED->setIntegerTypeSourceInfo(TI);
else
ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
ED->setPromotionType(ED->getIntegerType());
}
} else {
// struct/union/class
// FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
// struct X { int A; } D; D should chain to X.
if (getLangOpts().CPlusPlus) {
// FIXME: Look for a way to use RecordDecl for simple structs.
New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
cast_or_null<CXXRecordDecl>(PrevDecl));
if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
StdBadAlloc = cast<CXXRecordDecl>(New);
} else
New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
cast_or_null<RecordDecl>(PrevDecl));
}
// C++11 [dcl.type]p3:
// A type-specifier-seq shall not define a class or enumeration [...].
if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
<< Context.getTagDeclType(New);
Invalid = true;
}
// Maybe add qualifier info.
if (SS.isNotEmpty()) {
if (SS.isSet()) {
// If this is either a declaration or a definition, check the
// nested-name-specifier against the current context. We don't do this
// for explicit specializations, because they have similar checking
// (with more specific diagnostics) in the call to
// CheckMemberSpecialization, below.
if (!isExplicitSpecialization &&
(TUK == TUK_Definition || TUK == TUK_Declaration) &&
diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc))
Invalid = true;
New->setQualifierInfo(SS.getWithLocInContext(Context));
if (TemplateParameterLists.size() > 0) {
New->setTemplateParameterListsInfo(Context, TemplateParameterLists);
}
}
else
Invalid = true;
}
if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
// Add alignment attributes if necessary; these attributes are checked when
// the ASTContext lays out the structure.
//
// It is important for implementing the correct semantics that this
// happen here (in act on tag decl). The #pragma pack stack is
// maintained as a result of parser callbacks which can occur at
// many points during the parsing of a struct declaration (because
// the #pragma tokens are effectively skipped over during the
// parsing of the struct).
if (TUK == TUK_Definition) {
AddAlignmentAttributesForRecord(RD);
AddMsStructLayoutForRecord(RD);
}
}
if (ModulePrivateLoc.isValid()) {
if (isExplicitSpecialization)
Diag(New->getLocation(), diag::err_module_private_specialization)
<< 2
<< FixItHint::CreateRemoval(ModulePrivateLoc);
// __module_private__ does not apply to local classes. However, we only
// diagnose this as an error when the declaration specifiers are
// freestanding. Here, we just ignore the __module_private__.
else if (!SearchDC->isFunctionOrMethod())
New->setModulePrivate();
}
// If this is a specialization of a member class (of a class template),
// check the specialization.
if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous))
Invalid = true;
// If we're declaring or defining a tag in function prototype scope in C,
// note that this type can only be used within the function and add it to
// the list of decls to inject into the function definition scope.
if ((Name || Kind == TTK_Enum) &&
getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
if (getLangOpts().CPlusPlus) {
// C++ [dcl.fct]p6:
// Types shall not be defined in return or parameter types.
if (TUK == TUK_Definition && !IsTypeSpecifier) {
Diag(Loc, diag::err_type_defined_in_param_type)
<< Name;
Invalid = true;
}
} else {
Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
}
DeclsInPrototypeScope.push_back(New);
}
if (Invalid)
New->setInvalidDecl();
if (Attr)
ProcessDeclAttributeList(S, New, Attr);
// Set the lexical context. If the tag has a C++ scope specifier, the
// lexical context will be different from the semantic context.
New->setLexicalDeclContext(CurContext);
// Mark this as a friend decl if applicable.
// In Microsoft mode, a friend declaration also acts as a forward
// declaration so we always pass true to setObjectOfFriendDecl to make
// the tag name visible.
if (TUK == TUK_Friend)
New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
// Set the access specifier.
if (!Invalid && SearchDC->isRecord())
SetMemberAccessSpecifier(New, PrevDecl, AS);
if (TUK == TUK_Definition)
New->startDefinition();
// If this has an identifier, add it to the scope stack.
if (TUK == TUK_Friend) {
// We might be replacing an existing declaration in the lookup tables;
// if so, borrow its access specifier.
if (PrevDecl)
New->setAccess(PrevDecl->getAccess());
DeclContext *DC = New->getDeclContext()->getRedeclContext();
DC->makeDeclVisibleInContext(New);
if (Name) // can be null along some error paths
if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
} else if (Name) {
S = getNonFieldDeclScope(S);
PushOnScopeChains(New, S, !IsForwardReference);
if (IsForwardReference)
SearchDC->makeDeclVisibleInContext(New);
} else {
CurContext->addDecl(New);
}
// If this is the C FILE type, notify the AST context.
if (IdentifierInfo *II = New->getIdentifier())
if (!New->isInvalidDecl() &&
New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
II->isStr("FILE"))
Context.setFILEDecl(New);
if (PrevDecl)
mergeDeclAttributes(New, PrevDecl);
// If there's a #pragma GCC visibility in scope, set the visibility of this
// record.
AddPushedVisibilityAttribute(New);
OwnedDecl = true;
// In C++, don't return an invalid declaration. We can't recover well from
// the cases where we make the type anonymous.
return (Invalid && getLangOpts().CPlusPlus) ? nullptr : New;
}
void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
AdjustDeclIfTemplate(TagD);
TagDecl *Tag = cast<TagDecl>(TagD);
// Enter the tag context.
PushDeclContext(S, Tag);
ActOnDocumentableDecl(TagD);
// If there's a #pragma GCC visibility in scope, set the visibility of this
// record.
AddPushedVisibilityAttribute(Tag);
}
Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
assert(isa<ObjCContainerDecl>(IDecl) &&
"ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
DeclContext *OCD = cast<DeclContext>(IDecl);
assert(getContainingDC(OCD) == CurContext &&
"The next DeclContext should be lexically contained in the current one.");
CurContext = OCD;
return IDecl;
}
void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
SourceLocation FinalLoc,
bool IsFinalSpelledSealed,
SourceLocation LBraceLoc) {
AdjustDeclIfTemplate(TagD);
CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
FieldCollector->StartClass();
if (!Record->getIdentifier())
return;
if (FinalLoc.isValid())
Record->addAttr(new (Context)
FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
// C++ [class]p2:
// [...] The class-name is also inserted into the scope of the
// class itself; this is known as the injected-class-name. For
// purposes of access checking, the injected-class-name is treated
// as if it were a public member name.
CXXRecordDecl *InjectedClassName
= CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext,
Record->getLocStart(), Record->getLocation(),
Record->getIdentifier(),
/*PrevDecl=*/nullptr,
/*DelayTypeCreation=*/true);
Context.getTypeDeclType(InjectedClassName, Record);
InjectedClassName->setImplicit();
InjectedClassName->setAccess(AS_public);
if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
InjectedClassName->setDescribedClassTemplate(Template);
PushOnScopeChains(InjectedClassName, S);
assert(InjectedClassName->isInjectedClassName() &&
"Broken injected-class-name");
}
void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
SourceLocation RBraceLoc) {
AdjustDeclIfTemplate(TagD);
TagDecl *Tag = cast<TagDecl>(TagD);
Tag->setRBraceLoc(RBraceLoc);
// Make sure we "complete" the definition even it is invalid.
if (Tag->isBeingDefined()) {
assert(Tag->isInvalidDecl() && "We should already have completed it");
if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
RD->completeDefinition();
}
if (isa<CXXRecordDecl>(Tag))
FieldCollector->FinishClass();
// Exit this scope of this tag's definition.
PopDeclContext();
if (getCurLexicalContext()->isObjCContainer() &&
Tag->getDeclContext()->isFileContext())
Tag->setTopLevelDeclInObjCContainer();
// Notify the consumer that we've defined a tag.
if (!Tag->isInvalidDecl())
Consumer.HandleTagDeclDefinition(Tag);
}
void Sema::ActOnObjCContainerFinishDefinition() {
// Exit this scope of this interface definition.
PopDeclContext();
}
void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
assert(DC == CurContext && "Mismatch of container contexts");
OriginalLexicalContext = DC;
ActOnObjCContainerFinishDefinition();
}
void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
ActOnObjCContainerStartDefinition(cast<Decl>(DC));
OriginalLexicalContext = nullptr;
}
void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
AdjustDeclIfTemplate(TagD);
TagDecl *Tag = cast<TagDecl>(TagD);
Tag->setInvalidDecl();
// Make sure we "complete" the definition even it is invalid.
if (Tag->isBeingDefined()) {
if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
RD->completeDefinition();
}
// We're undoing ActOnTagStartDefinition here, not
// ActOnStartCXXMemberDeclarations, so we don't have to mess with
// the FieldCollector.
PopDeclContext();
}
// Note that FieldName may be null for anonymous bitfields.
ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
IdentifierInfo *FieldName,
QualType FieldTy, bool IsMsStruct,
Expr *BitWidth, bool *ZeroWidth) {
// Default to true; that shouldn't confuse checks for emptiness
if (ZeroWidth)
*ZeroWidth = true;
// C99 6.7.2.1p4 - verify the field type.
// C++ 9.6p3: A bit-field shall have integral or enumeration type.
if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
// Handle incomplete types with specific error.
if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
return ExprError();
if (FieldName)
return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
<< FieldName << FieldTy << BitWidth->getSourceRange();
return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
<< FieldTy << BitWidth->getSourceRange();
} else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
UPPC_BitFieldWidth))
return ExprError();
// If the bit-width is type- or value-dependent, don't try to check
// it now.
if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
return BitWidth;
llvm::APSInt Value;
ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
if (ICE.isInvalid())
return ICE;
BitWidth = ICE.get();
if (Value != 0 && ZeroWidth)
*ZeroWidth = false;
// Zero-width bitfield is ok for anonymous field.
if (Value == 0 && FieldName)
return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
if (Value.isSigned() && Value.isNegative()) {
if (FieldName)
return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
<< FieldName << Value.toString(10);
return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
<< Value.toString(10);
}
if (!FieldTy->isDependentType()) {
uint64_t TypeStorageSize = Context.getTypeSize(FieldTy);
uint64_t TypeWidth = Context.getIntWidth(FieldTy);
bool BitfieldIsOverwide = Value.ugt(TypeWidth);
// Over-wide bitfields are an error in C or when using the MSVC bitfield
// ABI.
bool CStdConstraintViolation =
BitfieldIsOverwide && !getLangOpts().CPlusPlus;
bool MSBitfieldViolation =
Value.ugt(TypeStorageSize) &&
(IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft());
if (CStdConstraintViolation || MSBitfieldViolation) {
unsigned DiagWidth =
CStdConstraintViolation ? TypeWidth : TypeStorageSize;
if (FieldName)
return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
<< FieldName << (unsigned)Value.getZExtValue()
<< !CStdConstraintViolation << DiagWidth;
return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_width)
<< (unsigned)Value.getZExtValue() << !CStdConstraintViolation
<< DiagWidth;
}
// Warn on types where the user might conceivably expect to get all
// specified bits as value bits: that's all integral types other than
// 'bool'.
if (BitfieldIsOverwide && !FieldTy->isBooleanType()) {
if (FieldName)
Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_width)
<< FieldName << (unsigned)Value.getZExtValue()
<< (unsigned)TypeWidth;
else
Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_width)
<< (unsigned)Value.getZExtValue() << (unsigned)TypeWidth;
}
}
return BitWidth;
}
/// ActOnField - Each field of a C struct/union is passed into this in order
/// to create a FieldDecl object for it.
Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
Declarator &D, Expr *BitfieldWidth) {
FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
DeclStart, D, static_cast<Expr*>(BitfieldWidth),
/*InitStyle=*/ICIS_NoInit, AS_public);
return Res;
}
/// HandleField - Analyze a field of a C struct or a C++ data member.
///
FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
SourceLocation DeclStart,
Declarator &D, Expr *BitWidth,
InClassInitStyle InitStyle,
AccessSpecifier AS) {
IdentifierInfo *II = D.getIdentifier();
SourceLocation Loc = DeclStart;
if (II) Loc = D.getIdentifierLoc();
TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
QualType T = TInfo->getType();
if (getLangOpts().CPlusPlus) {
CheckExtraCXXDefaultArguments(D);
if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
UPPC_DataMemberType)) {
D.setInvalidType();
T = Context.IntTy;
TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
}
}
// TR 18037 does not allow fields to be declared with address spaces.
if (T.getQualifiers().hasAddressSpace()) {
Diag(Loc, diag::err_field_with_address_space);
D.setInvalidType();
}
// OpenCL 1.2 spec, s6.9 r:
// The event type cannot be used to declare a structure or union field.
if (LangOpts.OpenCL && T->isEventT()) {
Diag(Loc, diag::err_event_t_struct_field);
D.setInvalidType();
}
DiagnoseFunctionSpecifiers(D.getDeclSpec());
if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
diag::err_invalid_thread)
<< DeclSpec::getSpecifierName(TSCS);
// Check to see if this name was declared as a member previously
NamedDecl *PrevDecl = nullptr;
LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
LookupName(Previous, S);
switch (Previous.getResultKind()) {
case LookupResult::Found:
case LookupResult::FoundUnresolvedValue:
PrevDecl = Previous.getAsSingle<NamedDecl>();
break;
case LookupResult::FoundOverloaded:
PrevDecl = Previous.getRepresentativeDecl();
break;
case LookupResult::NotFound:
case LookupResult::NotFoundInCurrentInstantiation:
case LookupResult::Ambiguous:
break;
}
Previous.suppressDiagnostics();
if (PrevDecl && PrevDecl->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
// Just pretend that we didn't see the previous declaration.
PrevDecl = nullptr;
}
if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
PrevDecl = nullptr;
bool Mutable
= (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
SourceLocation TSSL = D.getLocStart();
FieldDecl *NewFD
= CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
TSSL, AS, PrevDecl, &D);
if (NewFD->isInvalidDecl())
Record->setInvalidDecl();
if (D.getDeclSpec().isModulePrivateSpecified())
NewFD->setModulePrivate();
if (NewFD->isInvalidDecl() && PrevDecl) {
// Don't introduce NewFD into scope; there's already something
// with the same name in the same scope.
} else if (II) {
PushOnScopeChains(NewFD, S);
} else
Record->addDecl(NewFD);
return NewFD;
}
/// \brief Build a new FieldDecl and check its well-formedness.
///
/// This routine builds a new FieldDecl given the fields name, type,
/// record, etc. \p PrevDecl should refer to any previous declaration
/// with the same name and in the same scope as the field to be
/// created.
///
/// \returns a new FieldDecl.
///
/// \todo The Declarator argument is a hack. It will be removed once
FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
TypeSourceInfo *TInfo,
RecordDecl *Record, SourceLocation Loc,
bool Mutable, Expr *BitWidth,
InClassInitStyle InitStyle,
SourceLocation TSSL,
AccessSpecifier AS, NamedDecl *PrevDecl,
Declarator *D) {
IdentifierInfo *II = Name.getAsIdentifierInfo();
bool InvalidDecl = false;
if (D) InvalidDecl = D->isInvalidType();
// If we receive a broken type, recover by assuming 'int' and
// marking this declaration as invalid.
if (T.isNull()) {
InvalidDecl = true;
T = Context.IntTy;
}
QualType EltTy = Context.getBaseElementType(T);
if (!EltTy->isDependentType()) {
if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
// Fields of incomplete type force their record to be invalid.
Record->setInvalidDecl();
InvalidDecl = true;
} else {
NamedDecl *Def;
EltTy->isIncompleteType(&Def);
if (Def && Def->isInvalidDecl()) {
Record->setInvalidDecl();
InvalidDecl = true;
}
}
}
// OpenCL v1.2 s6.9.c: bitfields are not supported.
if (BitWidth && getLangOpts().OpenCL) {
Diag(Loc, diag::err_opencl_bitfields);
InvalidDecl = true;
}
// C99 6.7.2.1p8: A member of a structure or union may have any type other
// than a variably modified type.
if (!InvalidDecl && T->isVariablyModifiedType()) {
bool SizeIsNegative;
llvm::APSInt Oversized;
TypeSourceInfo *FixedTInfo =
TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
SizeIsNegative,
Oversized);
if (FixedTInfo) {
Diag(Loc, diag::warn_illegal_constant_array_size);
TInfo = FixedTInfo;
T = FixedTInfo->getType();
} else {
if (SizeIsNegative)
Diag(Loc, diag::err_typecheck_negative_array_size);
else if (Oversized.getBoolValue())
Diag(Loc, diag::err_array_too_large)
<< Oversized.toString(10);
else
Diag(Loc, diag::err_typecheck_field_variable_size);
InvalidDecl = true;
}
}
// Fields can not have abstract class types
if (!InvalidDecl && RequireNonAbstractType(Loc, T,
diag::err_abstract_type_in_decl,
AbstractFieldType))
InvalidDecl = true;
bool ZeroWidth = false;
if (InvalidDecl)
BitWidth = nullptr;
// If this is declared as a bit-field, check the bit-field.
if (BitWidth) {
BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
&ZeroWidth).get();
if (!BitWidth) {
InvalidDecl = true;
BitWidth = nullptr;
ZeroWidth = false;
}
}
// Check that 'mutable' is consistent with the type of the declaration.
if (!InvalidDecl && Mutable) {
unsigned DiagID = 0;
if (T->isReferenceType())
DiagID = getLangOpts().MSVCCompat ? diag::ext_mutable_reference
: diag::err_mutable_reference;
else if (T.isConstQualified())
DiagID = diag::err_mutable_const;
if (DiagID) {
SourceLocation ErrLoc = Loc;
if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
Diag(ErrLoc, DiagID);
if (DiagID != diag::ext_mutable_reference) {
Mutable = false;
InvalidDecl = true;
}
}
}
// C++11 [class.union]p8 (DR1460):
// At most one variant member of a union may have a
// brace-or-equal-initializer.
if (InitStyle != ICIS_NoInit)
checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
BitWidth, Mutable, InitStyle);
if (InvalidDecl)
NewFD->setInvalidDecl();
if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
Diag(Loc, diag::err_duplicate_member) << II;
Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
NewFD->setInvalidDecl();
}
if (!InvalidDecl && getLangOpts().CPlusPlus) {
if (Record->isUnion()) {
if (const RecordType *RT = EltTy->getAs<RecordType>()) {
CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
if (RDecl->getDefinition()) {
// C++ [class.union]p1: An object of a class with a non-trivial
// constructor, a non-trivial copy constructor, a non-trivial
// destructor, or a non-trivial copy assignment operator
// cannot be a member of a union, nor can an array of such
// objects.
if (CheckNontrivialField(NewFD))
NewFD->setInvalidDecl();
}
}
// C++ [class.union]p1: If a union contains a member of reference type,
// the program is ill-formed, except when compiling with MSVC extensions
// enabled.
if (EltTy->isReferenceType()) {
Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
diag::ext_union_member_of_reference_type :
diag::err_union_member_of_reference_type)
<< NewFD->getDeclName() << EltTy;
if (!getLangOpts().MicrosoftExt)
NewFD->setInvalidDecl();
}
}
}
// FIXME: We need to pass in the attributes given an AST
// representation, not a parser representation.
if (D) {
// FIXME: The current scope is almost... but not entirely... correct here.
ProcessDeclAttributes(getCurScope(), NewFD, *D);
if (NewFD->hasAttrs())
CheckAlignasUnderalignment(NewFD);
}
// In auto-retain/release, infer strong retension for fields of
// retainable type.
if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
NewFD->setInvalidDecl();
if (T.isObjCGCWeak())
Diag(Loc, diag::warn_attribute_weak_on_field);
NewFD->setAccess(AS);
return NewFD;
}
bool Sema::CheckNontrivialField(FieldDecl *FD) {
assert(FD);
assert(getLangOpts().CPlusPlus && "valid check only for C++");
if (FD->isInvalidDecl() || FD->getType()->isDependentType())
return false;
QualType EltTy = Context.getBaseElementType(FD->getType());
if (const RecordType *RT = EltTy->getAs<RecordType>()) {
CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
if (RDecl->getDefinition()) {
// We check for copy constructors before constructors
// because otherwise we'll never get complaints about
// copy constructors.
CXXSpecialMember member = CXXInvalid;
// We're required to check for any non-trivial constructors. Since the
// implicit default constructor is suppressed if there are any
// user-declared constructors, we just need to check that there is a
// trivial default constructor and a trivial copy constructor. (We don't
// worry about move constructors here, since this is a C++98 check.)
if (RDecl->hasNonTrivialCopyConstructor())
member = CXXCopyConstructor;
else if (!RDecl->hasTrivialDefaultConstructor())
member = CXXDefaultConstructor;
else if (RDecl->hasNonTrivialCopyAssignment())
member = CXXCopyAssignment;
else if (RDecl->hasNonTrivialDestructor())
member = CXXDestructor;
if (member != CXXInvalid) {
if (!getLangOpts().CPlusPlus11 &&
getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
// Objective-C++ ARC: it is an error to have a non-trivial field of
// a union. However, system headers in Objective-C programs
// occasionally have Objective-C lifetime objects within unions,
// and rather than cause the program to fail, we make those
// members unavailable.
SourceLocation Loc = FD->getLocation();
if (getSourceManager().isInSystemHeader(Loc)) {
if (!FD->hasAttr<UnavailableAttr>())
FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
UnavailableAttr::IR_ARCFieldWithOwnership, Loc));
return false;
}
}
Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
diag::err_illegal_union_or_anon_struct_member)
<< FD->getParent()->isUnion() << FD->getDeclName() << member;
DiagnoseNontrivial(RDecl, member);
return !getLangOpts().CPlusPlus11;
}
}
}
return false;
}
/// TranslateIvarVisibility - Translate visibility from a token ID to an
/// AST enum value.
static ObjCIvarDecl::AccessControl
TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
switch (ivarVisibility) {
default: llvm_unreachable("Unknown visitibility kind");
case tok::objc_private: return ObjCIvarDecl::Private;
case tok::objc_public: return ObjCIvarDecl::Public;
case tok::objc_protected: return ObjCIvarDecl::Protected;
case tok::objc_package: return ObjCIvarDecl::Package;
}
}
/// ActOnIvar - Each ivar field of an objective-c class is passed into this
/// in order to create an IvarDecl object for it.
Decl *Sema::ActOnIvar(Scope *S,
SourceLocation DeclStart,
Declarator &D, Expr *BitfieldWidth,
tok::ObjCKeywordKind Visibility) {
IdentifierInfo *II = D.getIdentifier();
Expr *BitWidth = (Expr*)BitfieldWidth;
SourceLocation Loc = DeclStart;
if (II) Loc = D.getIdentifierLoc();
// FIXME: Unnamed fields can be handled in various different ways, for
// example, unnamed unions inject all members into the struct namespace!
TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
QualType T = TInfo->getType();
if (BitWidth) {
// 6.7.2.1p3, 6.7.2.1p4
BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
if (!BitWidth)
D.setInvalidType();
} else {
// Not a bitfield.
// validate II.
}
if (T->isReferenceType()) {
Diag(Loc, diag::err_ivar_reference_type);
D.setInvalidType();
}
// C99 6.7.2.1p8: A member of a structure or union may have any type other
// than a variably modified type.
else if (T->isVariablyModifiedType()) {
Diag(Loc, diag::err_typecheck_ivar_variable_size);
D.setInvalidType();
}
// Get the visibility (access control) for this ivar.
ObjCIvarDecl::AccessControl ac =
Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
: ObjCIvarDecl::None;
// Must set ivar's DeclContext to its enclosing interface.
ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
return nullptr;
ObjCContainerDecl *EnclosingContext;
if (ObjCImplementationDecl *IMPDecl =
dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
if (LangOpts.ObjCRuntime.isFragile()) {
// Case of ivar declared in an implementation. Context is that of its class.
EnclosingContext = IMPDecl->getClassInterface();
assert(EnclosingContext && "Implementation has no class interface!");
}
else
EnclosingContext = EnclosingDecl;
} else {
if (ObjCCategoryDecl *CDecl =
dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
return nullptr;
}
}
EnclosingContext = EnclosingDecl;
}
// Construct the decl.
ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
DeclStart, Loc, II, T,
TInfo, ac, (Expr *)BitfieldWidth);
if (II) {
NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
ForRedeclaration);
if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
&& !isa<TagDecl>(PrevDecl)) {
Diag(Loc, diag::err_duplicate_member) << II;
Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
NewID->setInvalidDecl();
}
}
// Process attributes attached to the ivar.
ProcessDeclAttributes(S, NewID, D);
if (D.isInvalidType())
NewID->setInvalidDecl();
// In ARC, infer 'retaining' for ivars of retainable type.
if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
NewID->setInvalidDecl();
if (D.getDeclSpec().isModulePrivateSpecified())
NewID->setModulePrivate();
if (II) {
// FIXME: When interfaces are DeclContexts, we'll need to add
// these to the interface.
S->AddDecl(NewID);
IdResolver.AddDecl(NewID);
}
if (LangOpts.ObjCRuntime.isNonFragile() &&
!NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
Diag(Loc, diag::warn_ivars_in_interface);
return NewID;
}
/// ActOnLastBitfield - This routine handles synthesized bitfields rules for
/// class and class extensions. For every class \@interface and class
/// extension \@interface, if the last ivar is a bitfield of any type,
/// then add an implicit `char :0` ivar to the end of that interface.
void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
SmallVectorImpl<Decl *> &AllIvarDecls) {
if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
return;
Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0)
return;
ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
if (!ID) {
if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
if (!CD->IsClassExtension())
return;
}
// No need to add this to end of @implementation.
else
return;
}
// All conditions are met. Add a new bitfield to the tail end of ivars.
llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
DeclLoc, DeclLoc, nullptr,
Context.CharTy,
Context.getTrivialTypeSourceInfo(Context.CharTy,
DeclLoc),
ObjCIvarDecl::Private, BW,
true);
AllIvarDecls.push_back(Ivar);
}
void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
ArrayRef<Decl *> Fields, SourceLocation LBrac,
SourceLocation RBrac, AttributeList *Attr) {
assert(EnclosingDecl && "missing record or interface decl");
// If this is an Objective-C @implementation or category and we have
// new fields here we should reset the layout of the interface since
// it will now change.
if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
switch (DC->getKind()) {
default: break;
case Decl::ObjCCategory:
Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
break;
case Decl::ObjCImplementation:
Context.
ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
break;
}
}
RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
// Start counting up the number of named members; make sure to include
// members of anonymous structs and unions in the total.
unsigned NumNamedMembers = 0;
if (Record) {
for (const auto *I : Record->decls()) {
if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
if (IFD->getDeclName())
++NumNamedMembers;
}
}
// Verify that all the fields are okay.
SmallVector<FieldDecl*, 32> RecFields;
bool ARCErrReported = false;
for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
i != end; ++i) {
FieldDecl *FD = cast<FieldDecl>(*i);
// Get the type for the field.
const Type *FDTy = FD->getType().getTypePtr();
if (!FD->isAnonymousStructOrUnion()) {
// Remember all fields written by the user.
RecFields.push_back(FD);
}
// If the field is already invalid for some reason, don't emit more
// diagnostics about it.
if (FD->isInvalidDecl()) {
EnclosingDecl->setInvalidDecl();
continue;
}
// C99 6.7.2.1p2:
// A structure or union shall not contain a member with
// incomplete or function type (hence, a structure shall not
// contain an instance of itself, but may contain a pointer to
// an instance of itself), except that the last member of a
// structure with more than one named member may have incomplete
// array type; such a structure (and any union containing,
// possibly recursively, a member that is such a structure)
// shall not be a member of a structure or an element of an
// array.
if (FDTy->isFunctionType()) {
// Field declared as a function.
Diag(FD->getLocation(), diag::err_field_declared_as_function)
<< FD->getDeclName();
FD->setInvalidDecl();
EnclosingDecl->setInvalidDecl();
continue;
} else if (FDTy->isIncompleteArrayType() && Record &&
((i + 1 == Fields.end() && !Record->isUnion()) ||
((getLangOpts().MicrosoftExt ||
getLangOpts().CPlusPlus) &&
(i + 1 == Fields.end() || Record->isUnion())))) {
// Flexible array member.
// Microsoft and g++ is more permissive regarding flexible array.
// It will accept flexible array in union and also
// as the sole element of a struct/class.
unsigned DiagID = 0;
if (Record->isUnion())
DiagID = getLangOpts().MicrosoftExt
? diag::ext_flexible_array_union_ms
: getLangOpts().CPlusPlus
? diag::ext_flexible_array_union_gnu
: diag::err_flexible_array_union;
else if (Fields.size() == 1)
DiagID = getLangOpts().MicrosoftExt
? diag::ext_flexible_array_empty_aggregate_ms
: getLangOpts().CPlusPlus
? diag::ext_flexible_array_empty_aggregate_gnu
: NumNamedMembers < 1
? diag::err_flexible_array_empty_aggregate
: 0;
if (DiagID)
Diag(FD->getLocation(), DiagID) << FD->getDeclName()
<< Record->getTagKind();
// While the layout of types that contain virtual bases is not specified
// by the C++ standard, both the Itanium and Microsoft C++ ABIs place
// virtual bases after the derived members. This would make a flexible
// array member declared at the end of an object not adjacent to the end
// of the type.
if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record))
if (RD->getNumVBases() != 0)
Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
<< FD->getDeclName() << Record->getTagKind();
if (!getLangOpts().C99)
Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
<< FD->getDeclName() << Record->getTagKind();
// If the element type has a non-trivial destructor, we would not
// implicitly destroy the elements, so disallow it for now.
//
// FIXME: GCC allows this. We should probably either implicitly delete
// the destructor of the containing class, or just allow this.
QualType BaseElem = Context.getBaseElementType(FD->getType());
if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
<< FD->getDeclName() << FD->getType();
FD->setInvalidDecl();
EnclosingDecl->setInvalidDecl();
continue;
}
// Okay, we have a legal flexible array member at the end of the struct.
Record->setHasFlexibleArrayMember(true);
} else if (!FDTy->isDependentType() &&
RequireCompleteType(FD->getLocation(), FD->getType(),
diag::err_field_incomplete)) {
// Incomplete type
FD->setInvalidDecl();
EnclosingDecl->setInvalidDecl();
continue;
} else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
// A type which contains a flexible array member is considered to be a
// flexible array member.
Record->setHasFlexibleArrayMember(true);
if (!Record->isUnion()) {
// If this is a struct/class and this is not the last element, reject
// it. Note that GCC supports variable sized arrays in the middle of
// structures.
if (i + 1 != Fields.end())
Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
<< FD->getDeclName() << FD->getType();
else {
// We support flexible arrays at the end of structs in
// other structs as an extension.
Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
<< FD->getDeclName();
}
}
}
if (isa<ObjCContainerDecl>(EnclosingDecl) &&
RequireNonAbstractType(FD->getLocation(), FD->getType(),
diag::err_abstract_type_in_decl,
AbstractIvarType)) {
// Ivars can not have abstract class types
FD->setInvalidDecl();
}
if (Record && FDTTy->getDecl()->hasObjectMember())
Record->setHasObjectMember(true);
if (Record && FDTTy->getDecl()->hasVolatileMember())
Record->setHasVolatileMember(true);
} else if (FDTy->isObjCObjectType()) {
/// A field cannot be an Objective-c object
Diag(FD->getLocation(), diag::err_statically_allocated_object)
<< FixItHint::CreateInsertion(FD->getLocation(), "*");
QualType T = Context.getObjCObjectPointerType(FD->getType());
FD->setType(T);
} else if (getLangOpts().ObjCAutoRefCount && Record && !ARCErrReported &&
(!getLangOpts().CPlusPlus || Record->isUnion())) {
// It's an error in ARC if a field has lifetime.
// We don't want to report this in a system header, though,
// so we just make the field unavailable.
// FIXME: that's really not sufficient; we need to make the type
// itself invalid to, say, initialize or copy.
QualType T = FD->getType();
Qualifiers::ObjCLifetime lifetime = T.getObjCLifetime();
if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone) {
SourceLocation loc = FD->getLocation();
if (getSourceManager().isInSystemHeader(loc)) {
if (!FD->hasAttr<UnavailableAttr>()) {
FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
UnavailableAttr::IR_ARCFieldWithOwnership, loc));
}
} else {
Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag)
<< T->isBlockPointerType() << Record->getTagKind();
}
ARCErrReported = true;
}
} else if (getLangOpts().ObjC1 &&
getLangOpts().getGC() != LangOptions::NonGC &&
Record && !Record->hasObjectMember()) {
if (FD->getType()->isObjCObjectPointerType() ||
FD->getType().isObjCGCStrong())
Record->setHasObjectMember(true);
else if (Context.getAsArrayType(FD->getType())) {
QualType BaseType = Context.getBaseElementType(FD->getType());
if (BaseType->isRecordType() &&
BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
Record->setHasObjectMember(true);
else if (BaseType->isObjCObjectPointerType() ||
BaseType.isObjCGCStrong())
Record->setHasObjectMember(true);
}
}
if (Record && FD->getType().isVolatileQualified())
Record->setHasVolatileMember(true);
// Keep track of the number of named members.
if (FD->getIdentifier())
++NumNamedMembers;
}
// Okay, we successfully defined 'Record'.
if (Record) {
bool Completed = false;
if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
if (!CXXRecord->isInvalidDecl()) {
// Set access bits correctly on the directly-declared conversions.
for (CXXRecordDecl::conversion_iterator
I = CXXRecord->conversion_begin(),
E = CXXRecord->conversion_end(); I != E; ++I)
I.setAccess((*I)->getAccess());
if (!CXXRecord->isDependentType()) {
if (CXXRecord->hasUserDeclaredDestructor()) {
// Adjust user-defined destructor exception spec.
if (getLangOpts().CPlusPlus11)
AdjustDestructorExceptionSpec(CXXRecord,
CXXRecord->getDestructor());
}
// Add any implicitly-declared members to this class.
AddImplicitlyDeclaredMembersToClass(CXXRecord);
// If we have virtual base classes, we may end up finding multiple
// final overriders for a given virtual function. Check for this
// problem now.
if (CXXRecord->getNumVBases()) {
CXXFinalOverriderMap FinalOverriders;
CXXRecord->getFinalOverriders(FinalOverriders);
for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
MEnd = FinalOverriders.end();
M != MEnd; ++M) {
for (OverridingMethods::iterator SO = M->second.begin(),
SOEnd = M->second.end();
SO != SOEnd; ++SO) {
assert(SO->second.size() > 0 &&
"Virtual function without overridding functions?");
if (SO->second.size() == 1)
continue;
// C++ [class.virtual]p2:
// In a derived class, if a virtual member function of a base
// class subobject has more than one final overrider the
// program is ill-formed.
Diag(Record->getLocation(), diag::err_multiple_final_overriders)
<< (const NamedDecl *)M->first << Record;
Diag(M->first->getLocation(),
diag::note_overridden_virtual_function);
for (OverridingMethods::overriding_iterator
OM = SO->second.begin(),
OMEnd = SO->second.end();
OM != OMEnd; ++OM)
Diag(OM->Method->getLocation(), diag::note_final_overrider)
<< (const NamedDecl *)M->first << OM->Method->getParent();
Record->setInvalidDecl();
}
}
CXXRecord->completeDefinition(&FinalOverriders);
Completed = true;
}
}
}
}
if (!Completed)
Record->completeDefinition();
if (Record->hasAttrs()) {
CheckAlignasUnderalignment(Record);
if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
IA->getRange(), IA->getBestCase(),
IA->getSemanticSpelling());
}
// Check if the structure/union declaration is a type that can have zero
// size in C. For C this is a language extension, for C++ it may cause
// compatibility problems.
bool CheckForZeroSize;
if (!getLangOpts().CPlusPlus) {
CheckForZeroSize = true;
} else {
// For C++ filter out types that cannot be referenced in C code.
CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
CheckForZeroSize =
CXXRecord->getLexicalDeclContext()->isExternCContext() &&
!CXXRecord->isDependentType() &&
CXXRecord->isCLike();
}
if (CheckForZeroSize) {
bool ZeroSize = true;
bool IsEmpty = true;
unsigned NonBitFields = 0;
for (RecordDecl::field_iterator I = Record->field_begin(),
E = Record->field_end();
(NonBitFields == 0 || ZeroSize) && I != E; ++I) {
IsEmpty = false;
if (I->isUnnamedBitfield()) {
if (I->getBitWidthValue(Context) > 0)
ZeroSize = false;
} else {
++NonBitFields;
QualType FieldType = I->getType();
if (FieldType->isIncompleteType() ||
!Context.getTypeSizeInChars(FieldType).isZero())
ZeroSize = false;
}
}
// Empty structs are an extension in C (C99 6.7.2.1p7). They are
// allowed in C++, but warn if its declaration is inside
// extern "C" block.
if (ZeroSize) {
Diag(RecLoc, getLangOpts().CPlusPlus ?
diag::warn_zero_size_struct_union_in_extern_c :
diag::warn_zero_size_struct_union_compat)
<< IsEmpty << Record->isUnion() << (NonBitFields > 1);
}
// Structs without named members are extension in C (C99 6.7.2.1p7),
// but are accepted by GCC.
if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
diag::ext_no_named_members_in_struct_union)
<< Record->isUnion();
}
}
} else {
ObjCIvarDecl **ClsFields =
reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
ID->setEndOfDefinitionLoc(RBrac);
// Add ivar's to class's DeclContext.
for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
ClsFields[i]->setLexicalDeclContext(ID);
ID->addDecl(ClsFields[i]);
}
// Must enforce the rule that ivars in the base classes may not be
// duplicates.
if (ID->getSuperClass())
DiagnoseDuplicateIvars(ID, ID->getSuperClass());
} else if (ObjCImplementationDecl *IMPDecl =
dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
// Ivar declared in @implementation never belongs to the implementation.
// Only it is in implementation's lexical context.
ClsFields[I]->setLexicalDeclContext(IMPDecl);
CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
IMPDecl->setIvarLBraceLoc(LBrac);
IMPDecl->setIvarRBraceLoc(RBrac);
} else if (ObjCCategoryDecl *CDecl =
dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
// case of ivars in class extension; all other cases have been
// reported as errors elsewhere.
// FIXME. Class extension does not have a LocEnd field.
// CDecl->setLocEnd(RBrac);
// Add ivar's to class extension's DeclContext.
// Diagnose redeclaration of private ivars.
ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
if (IDecl) {
if (const ObjCIvarDecl *ClsIvar =
IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
Diag(ClsFields[i]->getLocation(),
diag::err_duplicate_ivar_declaration);
Diag(ClsIvar->getLocation(), diag::note_previous_definition);
continue;
}
for (const auto *Ext : IDecl->known_extensions()) {
if (const ObjCIvarDecl *ClsExtIvar
= Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
Diag(ClsFields[i]->getLocation(),
diag::err_duplicate_ivar_declaration);
Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
continue;
}
}
}
ClsFields[i]->setLexicalDeclContext(CDecl);
CDecl->addDecl(ClsFields[i]);
}
CDecl->setIvarLBraceLoc(LBrac);
CDecl->setIvarRBraceLoc(RBrac);
}
}
if (Attr)
ProcessDeclAttributeList(S, Record, Attr);
}
/// \brief Determine whether the given integral value is representable within
/// the given type T.
static bool isRepresentableIntegerValue(ASTContext &Context,
llvm::APSInt &Value,
QualType T) {
assert(T->isIntegralType(Context) && "Integral type required!");
unsigned BitWidth = Context.getIntWidth(T);
if (Value.isUnsigned() || Value.isNonNegative()) {
if (T->isSignedIntegerOrEnumerationType())
--BitWidth;
return Value.getActiveBits() <= BitWidth;
}
return Value.getMinSignedBits() <= BitWidth;
}
// \brief Given an integral type, return the next larger integral type
// (or a NULL type of no such type exists).
static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
// FIXME: Int128/UInt128 support, which also needs to be introduced into
// enum checking below.
assert(T->isIntegralType(Context) && "Integral type required!");
const unsigned NumTypes = 4;
QualType SignedIntegralTypes[NumTypes] = {
Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
};
QualType UnsignedIntegralTypes[NumTypes] = {
Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
Context.UnsignedLongLongTy
};
unsigned BitWidth = Context.getTypeSize(T);
QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
: UnsignedIntegralTypes;
for (unsigned I = 0; I != NumTypes; ++I)
if (Context.getTypeSize(Types[I]) > BitWidth)
return Types[I];
return QualType();
}
EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
EnumConstantDecl *LastEnumConst,
SourceLocation IdLoc,
IdentifierInfo *Id,
Expr *Val) {
unsigned IntWidth = Context.getTargetInfo().getIntWidth();
llvm::APSInt EnumVal(IntWidth);
QualType EltTy;
if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
Val = nullptr;
if (Val)
Val = DefaultLvalueConversion(Val).get();
if (Val) {
if (Enum->isDependentType() || Val->isTypeDependent())
EltTy = Context.DependentTy;
else {
SourceLocation ExpLoc;
if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
!getLangOpts().MSVCCompat) {
// C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
// constant-expression in the enumerator-definition shall be a converted
// constant expression of the underlying type.
EltTy = Enum->getIntegerType();
ExprResult Converted =
CheckConvertedConstantExpression(Val, EltTy, EnumVal,
CCEK_Enumerator);
if (Converted.isInvalid())
Val = nullptr;
else
Val = Converted.get();
} else if (!Val->isValueDependent() &&
!(Val = VerifyIntegerConstantExpression(Val,
&EnumVal).get())) {
// C99 6.7.2.2p2: Make sure we have an integer constant expression.
} else {
if (Enum->isFixed()) {
EltTy = Enum->getIntegerType();
// In Obj-C and Microsoft mode, require the enumeration value to be
// representable in the underlying type of the enumeration. In C++11,
// we perform a non-narrowing conversion as part of converted constant
// expression checking.
if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
if (getLangOpts().MSVCCompat) {
Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
} else
Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
} else
Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
} else if (getLangOpts().CPlusPlus) {
// C++11 [dcl.enum]p5:
// If the underlying type is not fixed, the type of each enumerator
// is the type of its initializing value:
// - If an initializer is specified for an enumerator, the
// initializing value has the same type as the expression.
EltTy = Val->getType();
} else {
// C99 6.7.2.2p2:
// The expression that defines the value of an enumeration constant
// shall be an integer constant expression that has a value
// representable as an int.
// Complain if the value is not representable in an int.
if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
Diag(IdLoc, diag::ext_enum_value_not_int)
<< EnumVal.toString(10) << Val->getSourceRange()
<< (EnumVal.isUnsigned() || EnumVal.isNonNegative());
else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
// Force the type of the expression to 'int'.
Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
}
EltTy = Val->getType();
}
}
}
}
if (!Val) {
if (Enum->isDependentType())
EltTy = Context.DependentTy;
else if (!LastEnumConst) {
// C++0x [dcl.enum]p5:
// If the underlying type is not fixed, the type of each enumerator
// is the type of its initializing value:
// - If no initializer is specified for the first enumerator, the
// initializing value has an unspecified integral type.
//
// GCC uses 'int' for its unspecified integral type, as does
// C99 6.7.2.2p3.
if (Enum->isFixed()) {
EltTy = Enum->getIntegerType();
}
else {
EltTy = Context.IntTy;
}
} else {
// Assign the last value + 1.
EnumVal = LastEnumConst->getInitVal();
++EnumVal;
EltTy = LastEnumConst->getType();
// Check for overflow on increment.
if (EnumVal < LastEnumConst->getInitVal()) {
// C++0x [dcl.enum]p5:
// If the underlying type is not fixed, the type of each enumerator
// is the type of its initializing value:
//
// - Otherwise the type of the initializing value is the same as
// the type of the initializing value of the preceding enumerator
// unless the incremented value is not representable in that type,
// in which case the type is an unspecified integral type
// sufficient to contain the incremented value. If no such type
// exists, the program is ill-formed.
QualType T = getNextLargerIntegralType(Context, EltTy);
if (T.isNull() || Enum->isFixed()) {
// There is no integral type larger enough to represent this
// value. Complain, then allow the value to wrap around.
EnumVal = LastEnumConst->getInitVal();
EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
++EnumVal;
if (Enum->isFixed())
// When the underlying type is fixed, this is ill-formed.
Diag(IdLoc, diag::err_enumerator_wrapped)
<< EnumVal.toString(10)
<< EltTy;
else
Diag(IdLoc, diag::ext_enumerator_increment_too_large)
<< EnumVal.toString(10);
} else {
EltTy = T;
}
// Retrieve the last enumerator's value, extent that type to the
// type that is supposed to be large enough to represent the incremented
// value, then increment.
EnumVal = LastEnumConst->getInitVal();
EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
++EnumVal;
// If we're not in C++, diagnose the overflow of enumerator values,
// which in C99 means that the enumerator value is not representable in
// an int (C99 6.7.2.2p2). However, we support GCC's extension that
// permits enumerator values that are representable in some larger
// integral type.
if (!getLangOpts().CPlusPlus && !T.isNull())
Diag(IdLoc, diag::warn_enum_value_overflow);
} else if (!getLangOpts().CPlusPlus &&
!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
// Enforce C99 6.7.2.2p2 even when we compute the next value.
Diag(IdLoc, diag::ext_enum_value_not_int)
<< EnumVal.toString(10) << 1;
}
}
}
if (!EltTy->isDependentType()) {
// Make the enumerator value match the signedness and size of the
// enumerator's type.
EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
}
return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
Val, EnumVal);
}
Sema::SkipBodyInfo Sema::shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
SourceLocation IILoc) {
if (!(getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) ||
!getLangOpts().CPlusPlus)
return SkipBodyInfo();
// We have an anonymous enum definition. Look up the first enumerator to
// determine if we should merge the definition with an existing one and
// skip the body.
NamedDecl *PrevDecl = LookupSingleName(S, II, IILoc, LookupOrdinaryName,
ForRedeclaration);
auto *PrevECD = dyn_cast_or_null<EnumConstantDecl>(PrevDecl);
if (!PrevECD)
return SkipBodyInfo();
EnumDecl *PrevED = cast<EnumDecl>(PrevECD->getDeclContext());
NamedDecl *Hidden;
if (!PrevED->getDeclName() && !hasVisibleDefinition(PrevED, &Hidden)) {
SkipBodyInfo Skip;
Skip.Previous = Hidden;
return Skip;
}
return SkipBodyInfo();
}
Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
SourceLocation IdLoc, IdentifierInfo *Id,
AttributeList *Attr,
SourceLocation EqualLoc, Expr *Val) {
EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
EnumConstantDecl *LastEnumConst =
cast_or_null<EnumConstantDecl>(lastEnumConst);
// The scope passed in may not be a decl scope. Zip up the scope tree until
// we find one that is.
S = getNonFieldDeclScope(S);
// Verify that there isn't already something declared with this name in this
// scope.
NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName,
ForRedeclaration);
if (PrevDecl && PrevDecl->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
// Just pretend that we didn't see the previous declaration.
PrevDecl = nullptr;
}
// C++ [class.mem]p15:
// If T is the name of a class, then each of the following shall have a name
// different from T:
// - every enumerator of every member of class T that is an unscoped
// enumerated type
if (!TheEnumDecl->isScoped())
DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
DeclarationNameInfo(Id, IdLoc));
EnumConstantDecl *New =
CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
if (!New)
return nullptr;
if (PrevDecl) {
// When in C++, we may get a TagDecl with the same name; in this case the
// enum constant will 'hide' the tag.
assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
"Received TagDecl when not in C++!");
if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S) &&
shouldLinkPossiblyHiddenDecl(PrevDecl, New)) {
if (isa<EnumConstantDecl>(PrevDecl))
Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
else
Diag(IdLoc, diag::err_redefinition) << Id;
Diag(PrevDecl->getLocation(), diag::note_previous_definition);
return nullptr;
}
}
// Process attributes.
if (Attr) ProcessDeclAttributeList(S, New, Attr);
// Register this decl in the current scope stack.
New->setAccess(TheEnumDecl->getAccess());
PushOnScopeChains(New, S);
ActOnDocumentableDecl(New);
return New;
}
// Returns true when the enum initial expression does not trigger the
// duplicate enum warning. A few common cases are exempted as follows:
// Element2 = Element1
// Element2 = Element1 + 1
// Element2 = Element1 - 1
// Where Element2 and Element1 are from the same enum.
static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
Expr *InitExpr = ECD->getInitExpr();
if (!InitExpr)
return true;
InitExpr = InitExpr->IgnoreImpCasts();
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
if (!BO->isAdditiveOp())
return true;
IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
if (!IL)
return true;
if (IL->getValue() != 1)
return true;
InitExpr = BO->getLHS();
}
// This checks if the elements are from the same enum.
DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
if (!DRE)
return true;
EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
if (!EnumConstant)
return true;
if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
Enum)
return true;
return false;
}
namespace {
struct DupKey {
int64_t val;
bool isTombstoneOrEmptyKey;
DupKey(int64_t val, bool isTombstoneOrEmptyKey)
: val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {}
};
static DupKey GetDupKey(const llvm::APSInt& Val) {
return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(),
false);
}
struct DenseMapInfoDupKey {
static DupKey getEmptyKey() { return DupKey(0, true); }
static DupKey getTombstoneKey() { return DupKey(1, true); }
static unsigned getHashValue(const DupKey Key) {
return (unsigned)(Key.val * 37);
}
static bool isEqual(const DupKey& LHS, const DupKey& RHS) {
return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey &&
LHS.val == RHS.val;
}
};
} // end anonymous namespace
// Emits a warning when an element is implicitly set a value that
// a previous element has already been set to.
static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
EnumDecl *Enum,
QualType EnumType) {
if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
return;
// Avoid anonymous enums
if (!Enum->getIdentifier())
return;
// Only check for small enums.
if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
return;
typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
typedef SmallVector<ECDVector *, 3> DuplicatesVector;
typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey>
ValueToVectorMap;
DuplicatesVector DupVector;
ValueToVectorMap EnumMap;
// Populate the EnumMap with all values represented by enum constants without
// an initialier.
for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
// Null EnumConstantDecl means a previous diagnostic has been emitted for
// this constant. Skip this enum since it may be ill-formed.
if (!ECD) {
return;
}
if (ECD->getInitExpr())
continue;
DupKey Key = GetDupKey(ECD->getInitVal());
DeclOrVector &Entry = EnumMap[Key];
// First time encountering this value.
if (Entry.isNull())
Entry = ECD;
}
// Create vectors for any values that has duplicates.
for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]);
if (!ValidDuplicateEnum(ECD, Enum))
continue;
DupKey Key = GetDupKey(ECD->getInitVal());
DeclOrVector& Entry = EnumMap[Key];
if (Entry.isNull())
continue;
if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
// Ensure constants are different.
if (D == ECD)
continue;
// Create new vector and push values onto it.
ECDVector *Vec = new ECDVector();
Vec->push_back(D);
Vec->push_back(ECD);
// Update entry to point to the duplicates vector.
Entry = Vec;
// Store the vector somewhere we can consult later for quick emission of
// diagnostics.
DupVector.push_back(Vec);
continue;
}
ECDVector *Vec = Entry.get<ECDVector*>();
// Make sure constants are not added more than once.
if (*Vec->begin() == ECD)
continue;
Vec->push_back(ECD);
}
// Emit diagnostics.
for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(),
DupVectorEnd = DupVector.end();
DupVectorIter != DupVectorEnd; ++DupVectorIter) {
ECDVector *Vec = *DupVectorIter;
assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
// Emit warning for one enum constant.
ECDVector::iterator I = Vec->begin();
S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values)
<< (*I)->getName() << (*I)->getInitVal().toString(10)
<< (*I)->getSourceRange();
++I;
// Emit one note for each of the remaining enum constants with
// the same value.
for (ECDVector::iterator E = Vec->end(); I != E; ++I)
S.Diag((*I)->getLocation(), diag::note_duplicate_element)
<< (*I)->getName() << (*I)->getInitVal().toString(10)
<< (*I)->getSourceRange();
delete Vec;
}
}
bool Sema::IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
bool AllowMask) const {
assert(ED->hasAttr<FlagEnumAttr>() && "looking for value in non-flag enum");
assert(ED->isCompleteDefinition() && "expected enum definition");
auto R = FlagBitsCache.insert(std::make_pair(ED, llvm::APInt()));
llvm::APInt &FlagBits = R.first->second;
if (R.second) {
for (auto *E : ED->enumerators()) {
const auto &EVal = E->getInitVal();
// Only single-bit enumerators introduce new flag values.
if (EVal.isPowerOf2())
FlagBits = FlagBits.zextOrSelf(EVal.getBitWidth()) | EVal;
}
}
// A value is in a flag enum if either its bits are a subset of the enum's
// flag bits (the first condition) or we are allowing masks and the same is
// true of its complement (the second condition). When masks are allowed, we
// allow the common idiom of ~(enum1 | enum2) to be a valid enum value.
//
// While it's true that any value could be used as a mask, the assumption is
// that a mask will have all of the insignificant bits set. Anything else is
// likely a logic error.
llvm::APInt FlagMask = ~FlagBits.zextOrTrunc(Val.getBitWidth());
return !(FlagMask & Val) || (AllowMask && !(FlagMask & ~Val));
}
void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
SourceLocation RBraceLoc, Decl *EnumDeclX,
ArrayRef<Decl *> Elements,
Scope *S, AttributeList *Attr) {
EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
QualType EnumType = Context.getTypeDeclType(Enum);
if (Attr)
ProcessDeclAttributeList(S, Enum, Attr);
if (Enum->isDependentType()) {
for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
EnumConstantDecl *ECD =
cast_or_null<EnumConstantDecl>(Elements[i]);
if (!ECD) continue;
ECD->setType(EnumType);
}
Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
return;
}
// TODO: If the result value doesn't fit in an int, it must be a long or long
// long value. ISO C does not support this, but GCC does as an extension,
// emit a warning.
unsigned IntWidth = Context.getTargetInfo().getIntWidth();
unsigned CharWidth = Context.getTargetInfo().getCharWidth();
unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
// Verify that all the values are okay, compute the size of the values, and
// reverse the list.
unsigned NumNegativeBits = 0;
unsigned NumPositiveBits = 0;
// Keep track of whether all elements have type int.
bool AllElementsInt = true;
for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
EnumConstantDecl *ECD =
cast_or_null<EnumConstantDecl>(Elements[i]);
if (!ECD) continue; // Already issued a diagnostic.
const llvm::APSInt &InitVal = ECD->getInitVal();
// Keep track of the size of positive and negative values.
if (InitVal.isUnsigned() || InitVal.isNonNegative())
NumPositiveBits = std::max(NumPositiveBits,
(unsigned)InitVal.getActiveBits());
else
NumNegativeBits = std::max(NumNegativeBits,
(unsigned)InitVal.getMinSignedBits());
// Keep track of whether every enum element has type int (very commmon).
if (AllElementsInt)
AllElementsInt = ECD->getType() == Context.IntTy;
}
// Figure out the type that should be used for this enum.
QualType BestType;
unsigned BestWidth;
// C++0x N3000 [conv.prom]p3:
// An rvalue of an unscoped enumeration type whose underlying
// type is not fixed can be converted to an rvalue of the first
// of the following types that can represent all the values of
// the enumeration: int, unsigned int, long int, unsigned long
// int, long long int, or unsigned long long int.
// C99 6.4.4.3p2:
// An identifier declared as an enumeration constant has type int.
// The C99 rule is modified by a gcc extension
QualType BestPromotionType;
bool Packed = Enum->hasAttr<PackedAttr>();
// -fshort-enums is the equivalent to specifying the packed attribute on all
// enum definitions.
if (LangOpts.ShortEnums)
Packed = true;
if (Enum->isFixed()) {
BestType = Enum->getIntegerType();
if (BestType->isPromotableIntegerType())
BestPromotionType = Context.getPromotedIntegerType(BestType);
else
BestPromotionType = BestType;
BestWidth = Context.getIntWidth(BestType);
}
else if (NumNegativeBits) {
// If there is a negative value, figure out the smallest integer type (of
// int/long/longlong) that fits.
// If it's packed, check also if it fits a char or a short.
if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
BestType = Context.SignedCharTy;
BestWidth = CharWidth;
} else if (Packed && NumNegativeBits <= ShortWidth &&
NumPositiveBits < ShortWidth) {
BestType = Context.ShortTy;
BestWidth = ShortWidth;
} else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
BestType = Context.IntTy;
BestWidth = IntWidth;
} else {
BestWidth = Context.getTargetInfo().getLongWidth();
if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
BestType = Context.LongTy;
} else {
BestWidth = Context.getTargetInfo().getLongLongWidth();
if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
Diag(Enum->getLocation(), diag::ext_enum_too_large);
BestType = Context.LongLongTy;
}
}
BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
} else {
// If there is no negative value, figure out the smallest type that fits
// all of the enumerator values.
// If it's packed, check also if it fits a char or a short.
if (Packed && NumPositiveBits <= CharWidth) {
BestType = Context.UnsignedCharTy;
BestPromotionType = Context.IntTy;
BestWidth = CharWidth;
} else if (Packed && NumPositiveBits <= ShortWidth) {
BestType = Context.UnsignedShortTy;
BestPromotionType = Context.IntTy;
BestWidth = ShortWidth;
} else if (NumPositiveBits <= IntWidth) {
BestType = Context.UnsignedIntTy;
BestWidth = IntWidth;
BestPromotionType
= (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
? Context.UnsignedIntTy : Context.IntTy;
} else if (NumPositiveBits <=
(BestWidth = Context.getTargetInfo().getLongWidth())) {
BestType = Context.UnsignedLongTy;
BestPromotionType
= (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
? Context.UnsignedLongTy : Context.LongTy;
} else {
BestWidth = Context.getTargetInfo().getLongLongWidth();
assert(NumPositiveBits <= BestWidth &&
"How could an initializer get larger than ULL?");
BestType = Context.UnsignedLongLongTy;
BestPromotionType
= (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
? Context.UnsignedLongLongTy : Context.LongLongTy;
}
}
// Loop over all of the enumerator constants, changing their types to match
// the type of the enum if needed.
for (auto *D : Elements) {
auto *ECD = cast_or_null<EnumConstantDecl>(D);
if (!ECD) continue; // Already issued a diagnostic.
// Standard C says the enumerators have int type, but we allow, as an
// extension, the enumerators to be larger than int size. If each
// enumerator value fits in an int, type it as an int, otherwise type it the
// same as the enumerator decl itself. This means that in "enum { X = 1U }"
// that X has type 'int', not 'unsigned'.
// Determine whether the value fits into an int.
llvm::APSInt InitVal = ECD->getInitVal();
// If it fits into an integer type, force it. Otherwise force it to match
// the enum decl type.
QualType NewTy;
unsigned NewWidth;
bool NewSign;
if (!getLangOpts().CPlusPlus &&
!Enum->isFixed() &&
isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
NewTy = Context.IntTy;
NewWidth = IntWidth;
NewSign = true;
} else if (ECD->getType() == BestType) {
// Already the right type!
if (getLangOpts().CPlusPlus)
// C++ [dcl.enum]p4: Following the closing brace of an
// enum-specifier, each enumerator has the type of its
// enumeration.
ECD->setType(EnumType);
continue;
} else {
NewTy = BestType;
NewWidth = BestWidth;
NewSign = BestType->isSignedIntegerOrEnumerationType();
}
// Adjust the APSInt value.
InitVal = InitVal.extOrTrunc(NewWidth);
InitVal.setIsSigned(NewSign);
ECD->setInitVal(InitVal);
// Adjust the Expr initializer and type.
if (ECD->getInitExpr() &&
!Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
CK_IntegralCast,
ECD->getInitExpr(),
/*base paths*/ nullptr,
VK_RValue));
if (getLangOpts().CPlusPlus)
// C++ [dcl.enum]p4: Following the closing brace of an
// enum-specifier, each enumerator has the type of its
// enumeration.
ECD->setType(EnumType);
else
ECD->setType(NewTy);
}
Enum->completeDefinition(BestType, BestPromotionType,
NumPositiveBits, NumNegativeBits);
CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
if (Enum->hasAttr<FlagEnumAttr>()) {
for (Decl *D : Elements) {
EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(D);
if (!ECD) continue; // Already issued a diagnostic.
llvm::APSInt InitVal = ECD->getInitVal();
if (InitVal != 0 && !InitVal.isPowerOf2() &&
!IsValueInFlagEnum(Enum, InitVal, true))
Diag(ECD->getLocation(), diag::warn_flag_enum_constant_out_of_range)
<< ECD << Enum;
}
}
// Now that the enum type is defined, ensure it's not been underaligned.
if (Enum->hasAttrs())
CheckAlignasUnderalignment(Enum);
}
Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
SourceLocation StartLoc,
SourceLocation EndLoc) {
StringLiteral *AsmString = cast<StringLiteral>(expr);
FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
AsmString, StartLoc,
EndLoc);
CurContext->addDecl(New);
return New;
}
static void checkModuleImportContext(Sema &S, Module *M,
SourceLocation ImportLoc, DeclContext *DC,
bool FromInclude = false) {
SourceLocation ExternCLoc;
if (auto *LSD = dyn_cast<LinkageSpecDecl>(DC)) {
switch (LSD->getLanguage()) {
case LinkageSpecDecl::lang_c:
if (ExternCLoc.isInvalid())
ExternCLoc = LSD->getLocStart();
break;
case LinkageSpecDecl::lang_cxx:
break;
}
DC = LSD->getParent();
}
while (isa<LinkageSpecDecl>(DC))
DC = DC->getParent();
if (!isa<TranslationUnitDecl>(DC)) {
S.Diag(ImportLoc, (FromInclude && S.isModuleVisible(M))
? diag::ext_module_import_not_at_top_level_noop
: diag::err_module_import_not_at_top_level_fatal)
<< M->getFullModuleName() << DC;
S.Diag(cast<Decl>(DC)->getLocStart(),
diag::note_module_import_not_at_top_level) << DC;
} else if (!M->IsExternC && ExternCLoc.isValid()) {
S.Diag(ImportLoc, diag::ext_module_import_in_extern_c)
<< M->getFullModuleName();
S.Diag(ExternCLoc, diag::note_module_import_in_extern_c);
}
}
void Sema::diagnoseMisplacedModuleImport(Module *M, SourceLocation ImportLoc) {
return checkModuleImportContext(*this, M, ImportLoc, CurContext);
}
DeclResult Sema::ActOnModuleImport(SourceLocation AtLoc,
SourceLocation ImportLoc,
ModuleIdPath Path) {
Module *Mod =
getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible,
/*IsIncludeDirective=*/false);
if (!Mod)
return true;
VisibleModules.setVisible(Mod, ImportLoc);
checkModuleImportContext(*this, Mod, ImportLoc, CurContext);
// FIXME: we should support importing a submodule within a different submodule
// of the same top-level module. Until we do, make it an error rather than
// silently ignoring the import.
if (Mod->getTopLevelModuleName() == getLangOpts().CurrentModule)
Diag(ImportLoc, diag::err_module_self_import)
<< Mod->getFullModuleName() << getLangOpts().CurrentModule;
else if (Mod->getTopLevelModuleName() == getLangOpts().ImplementationOfModule)
Diag(ImportLoc, diag::err_module_import_in_implementation)
<< Mod->getFullModuleName() << getLangOpts().ImplementationOfModule;
SmallVector<SourceLocation, 2> IdentifierLocs;
Module *ModCheck = Mod;
for (unsigned I = 0, N = Path.size(); I != N; ++I) {
// If we've run out of module parents, just drop the remaining identifiers.
// We need the length to be consistent.
if (!ModCheck)
break;
ModCheck = ModCheck->Parent;
IdentifierLocs.push_back(Path[I].second);
}
ImportDecl *Import = ImportDecl::Create(Context,
Context.getTranslationUnitDecl(),
AtLoc.isValid()? AtLoc : ImportLoc,
Mod, IdentifierLocs);
Context.getTranslationUnitDecl()->addDecl(Import);
return Import;
}
void Sema::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
// Determine whether we're in the #include buffer for a module. The #includes
// in that buffer do not qualify as module imports; they're just an
// implementation detail of us building the module.
//
// FIXME: Should we even get ActOnModuleInclude calls for those?
bool IsInModuleIncludes =
TUKind == TU_Module &&
getSourceManager().isWrittenInMainFile(DirectiveLoc);
// If this module import was due to an inclusion directive, create an
// implicit import declaration to capture it in the AST.
if (!IsInModuleIncludes) {
TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
DirectiveLoc, Mod,
DirectiveLoc);
TU->addDecl(ImportD);
Consumer.HandleImplicitImportDecl(ImportD);
}
getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc);
VisibleModules.setVisible(Mod, DirectiveLoc);
}
void Sema::ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod) {
checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext);
if (getLangOpts().ModulesLocalVisibility)
VisibleModulesStack.push_back(std::move(VisibleModules));
VisibleModules.setVisible(Mod, DirectiveLoc);
}
void Sema::ActOnModuleEnd(SourceLocation DirectiveLoc, Module *Mod) {
checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext);
if (getLangOpts().ModulesLocalVisibility) {
VisibleModules = std::move(VisibleModulesStack.back());
VisibleModulesStack.pop_back();
VisibleModules.setVisible(Mod, DirectiveLoc);
}
}
void Sema::createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
Module *Mod) {
// Bail if we're not allowed to implicitly import a module here.
if (isSFINAEContext() || !getLangOpts().ModulesErrorRecovery)
return;
// Create the implicit import declaration.
TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
Loc, Mod, Loc);
TU->addDecl(ImportD);
Consumer.HandleImplicitImportDecl(ImportD);
// Make the module visible.
getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc);
VisibleModules.setVisible(Mod, Loc);
}
void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
IdentifierInfo* AliasName,
SourceLocation PragmaLoc,
SourceLocation NameLoc,
SourceLocation AliasNameLoc) {
NamedDecl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
LookupOrdinaryName);
AsmLabelAttr *Attr =
AsmLabelAttr::CreateImplicit(Context, AliasName->getName(), AliasNameLoc);
// If a declaration that:
// 1) declares a function or a variable
// 2) has external linkage
// already exists, add a label attribute to it.
if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
if (isDeclExternC(PrevDecl))
PrevDecl->addAttr(Attr);
else
Diag(PrevDecl->getLocation(), diag::warn_redefine_extname_not_applied)
<< /*Variable*/(isa<FunctionDecl>(PrevDecl) ? 0 : 1) << PrevDecl;
// Otherwise, add a label atttibute to ExtnameUndeclaredIdentifiers.
} else
(void)ExtnameUndeclaredIdentifiers.insert(std::make_pair(Name, Attr));
}
void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
SourceLocation PragmaLoc,
SourceLocation NameLoc) {
Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
if (PrevDecl) {
PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
} else {
(void)WeakUndeclaredIdentifiers.insert(
std::pair<IdentifierInfo*,WeakInfo>
(Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
}
}
void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
IdentifierInfo* AliasName,
SourceLocation PragmaLoc,
SourceLocation NameLoc,
SourceLocation AliasNameLoc) {
Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
LookupOrdinaryName);
WeakInfo W = WeakInfo(Name, NameLoc);
if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
if (!PrevDecl->hasAttr<AliasAttr>())
if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
DeclApplyPragmaWeak(TUScope, ND, W);
} else {
(void)WeakUndeclaredIdentifiers.insert(
std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
}
}
Decl *Sema::getObjCDeclContext() const {
return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));
}
AvailabilityResult Sema::getCurContextAvailability() const {
const Decl *D = cast_or_null<Decl>(getCurObjCLexicalContext());
if (!D)
return AR_Available;
// If we are within an Objective-C method, we should consult
// both the availability of the method as well as the
// enclosing class. If the class is (say) deprecated,
// the entire method is considered deprecated from the
// purpose of checking if the current context is deprecated.
if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
AvailabilityResult R = MD->getAvailability();
if (R != AR_Available)
return R;
D = MD->getClassInterface();
}
// If we are within an Objective-c @implementation, it
// gets the same availability context as the @interface.
else if (const ObjCImplementationDecl *ID =
dyn_cast<ObjCImplementationDecl>(D)) {
D = ID->getClassInterface();
}
// Recover from user error.
return D ? D->getAvailability() : AR_Available;
}
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