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

3138 lines
112 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

//===--------------------- SemaLookup.cpp - Name Lookup ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements name lookup for C, C++, Objective-C, and
// Objective-C++.
//
//===----------------------------------------------------------------------===//
#include "clang/Sema/Sema.h"
#include "clang/Sema/SemaInternal.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/DeclSpec.h"
#include "clang/Sema/Scope.h"
#include "clang/Sema/ScopeInfo.h"
#include "clang/Sema/TemplateDeduction.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/Basic/Builtins.h"
#include "clang/Basic/LangOptions.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/Support/ErrorHandling.h"
#include <list>
#include <set>
#include <vector>
#include <iterator>
#include <utility>
#include <algorithm>
using namespace clang;
using namespace sema;
namespace {
class UnqualUsingEntry {
const DeclContext *Nominated;
const DeclContext *CommonAncestor;
public:
UnqualUsingEntry(const DeclContext *Nominated,
const DeclContext *CommonAncestor)
: Nominated(Nominated), CommonAncestor(CommonAncestor) {
}
const DeclContext *getCommonAncestor() const {
return CommonAncestor;
}
const DeclContext *getNominatedNamespace() const {
return Nominated;
}
// Sort by the pointer value of the common ancestor.
struct Comparator {
bool operator()(const UnqualUsingEntry &L, const UnqualUsingEntry &R) {
return L.getCommonAncestor() < R.getCommonAncestor();
}
bool operator()(const UnqualUsingEntry &E, const DeclContext *DC) {
return E.getCommonAncestor() < DC;
}
bool operator()(const DeclContext *DC, const UnqualUsingEntry &E) {
return DC < E.getCommonAncestor();
}
};
};
/// A collection of using directives, as used by C++ unqualified
/// lookup.
class UnqualUsingDirectiveSet {
typedef llvm::SmallVector<UnqualUsingEntry, 8> ListTy;
ListTy list;
llvm::SmallPtrSet<DeclContext*, 8> visited;
public:
UnqualUsingDirectiveSet() {}
void visitScopeChain(Scope *S, Scope *InnermostFileScope) {
// C++ [namespace.udir]p1:
// During unqualified name lookup, the names appear as if they
// were declared in the nearest enclosing namespace which contains
// both the using-directive and the nominated namespace.
DeclContext *InnermostFileDC
= static_cast<DeclContext*>(InnermostFileScope->getEntity());
assert(InnermostFileDC && InnermostFileDC->isFileContext());
for (; S; S = S->getParent()) {
if (DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity())) {
DeclContext *EffectiveDC = (Ctx->isFileContext() ? Ctx : InnermostFileDC);
visit(Ctx, EffectiveDC);
} else {
Scope::udir_iterator I = S->using_directives_begin(),
End = S->using_directives_end();
for (; I != End; ++I)
visit(*I, InnermostFileDC);
}
}
}
// Visits a context and collect all of its using directives
// recursively. Treats all using directives as if they were
// declared in the context.
//
// A given context is only every visited once, so it is important
// that contexts be visited from the inside out in order to get
// the effective DCs right.
void visit(DeclContext *DC, DeclContext *EffectiveDC) {
if (!visited.insert(DC))
return;
addUsingDirectives(DC, EffectiveDC);
}
// Visits a using directive and collects all of its using
// directives recursively. Treats all using directives as if they
// were declared in the effective DC.
void visit(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
DeclContext *NS = UD->getNominatedNamespace();
if (!visited.insert(NS))
return;
addUsingDirective(UD, EffectiveDC);
addUsingDirectives(NS, EffectiveDC);
}
// Adds all the using directives in a context (and those nominated
// by its using directives, transitively) as if they appeared in
// the given effective context.
void addUsingDirectives(DeclContext *DC, DeclContext *EffectiveDC) {
llvm::SmallVector<DeclContext*,4> queue;
while (true) {
DeclContext::udir_iterator I, End;
for (llvm::tie(I, End) = DC->getUsingDirectives(); I != End; ++I) {
UsingDirectiveDecl *UD = *I;
DeclContext *NS = UD->getNominatedNamespace();
if (visited.insert(NS)) {
addUsingDirective(UD, EffectiveDC);
queue.push_back(NS);
}
}
if (queue.empty())
return;
DC = queue.back();
queue.pop_back();
}
}
// Add a using directive as if it had been declared in the given
// context. This helps implement C++ [namespace.udir]p3:
// The using-directive is transitive: if a scope contains a
// using-directive that nominates a second namespace that itself
// contains using-directives, the effect is as if the
// using-directives from the second namespace also appeared in
// the first.
void addUsingDirective(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
// Find the common ancestor between the effective context and
// the nominated namespace.
DeclContext *Common = UD->getNominatedNamespace();
while (!Common->Encloses(EffectiveDC))
Common = Common->getParent();
Common = Common->getPrimaryContext();
list.push_back(UnqualUsingEntry(UD->getNominatedNamespace(), Common));
}
void done() {
std::sort(list.begin(), list.end(), UnqualUsingEntry::Comparator());
}
typedef ListTy::iterator iterator;
typedef ListTy::const_iterator const_iterator;
iterator begin() { return list.begin(); }
iterator end() { return list.end(); }
const_iterator begin() const { return list.begin(); }
const_iterator end() const { return list.end(); }
std::pair<const_iterator,const_iterator>
getNamespacesFor(DeclContext *DC) const {
return std::equal_range(begin(), end(), DC->getPrimaryContext(),
UnqualUsingEntry::Comparator());
}
};
}
// Retrieve the set of identifier namespaces that correspond to a
// specific kind of name lookup.
static inline unsigned getIDNS(Sema::LookupNameKind NameKind,
bool CPlusPlus,
bool Redeclaration) {
unsigned IDNS = 0;
switch (NameKind) {
case Sema::LookupOrdinaryName:
case Sema::LookupRedeclarationWithLinkage:
IDNS = Decl::IDNS_Ordinary;
if (CPlusPlus) {
IDNS |= Decl::IDNS_Tag | Decl::IDNS_Member | Decl::IDNS_Namespace;
if (Redeclaration) IDNS |= Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend;
}
break;
case Sema::LookupOperatorName:
// Operator lookup is its own crazy thing; it is not the same
// as (e.g.) looking up an operator name for redeclaration.
assert(!Redeclaration && "cannot do redeclaration operator lookup");
IDNS = Decl::IDNS_NonMemberOperator;
break;
case Sema::LookupTagName:
if (CPlusPlus) {
IDNS = Decl::IDNS_Type;
// When looking for a redeclaration of a tag name, we add:
// 1) TagFriend to find undeclared friend decls
// 2) Namespace because they can't "overload" with tag decls.
// 3) Tag because it includes class templates, which can't
// "overload" with tag decls.
if (Redeclaration)
IDNS |= Decl::IDNS_Tag | Decl::IDNS_TagFriend | Decl::IDNS_Namespace;
} else {
IDNS = Decl::IDNS_Tag;
}
break;
case Sema::LookupMemberName:
IDNS = Decl::IDNS_Member;
if (CPlusPlus)
IDNS |= Decl::IDNS_Tag | Decl::IDNS_Ordinary;
break;
case Sema::LookupNestedNameSpecifierName:
IDNS = Decl::IDNS_Type | Decl::IDNS_Namespace;
break;
case Sema::LookupNamespaceName:
IDNS = Decl::IDNS_Namespace;
break;
case Sema::LookupUsingDeclName:
IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag
| Decl::IDNS_Member | Decl::IDNS_Using;
break;
case Sema::LookupObjCProtocolName:
IDNS = Decl::IDNS_ObjCProtocol;
break;
case Sema::LookupAnyName:
IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member
| Decl::IDNS_Using | Decl::IDNS_Namespace | Decl::IDNS_ObjCProtocol
| Decl::IDNS_Type;
break;
}
return IDNS;
}
void LookupResult::configure() {
IDNS = getIDNS(LookupKind,
SemaRef.getLangOptions().CPlusPlus,
isForRedeclaration());
// If we're looking for one of the allocation or deallocation
// operators, make sure that the implicitly-declared new and delete
// operators can be found.
if (!isForRedeclaration()) {
switch (NameInfo.getName().getCXXOverloadedOperator()) {
case OO_New:
case OO_Delete:
case OO_Array_New:
case OO_Array_Delete:
SemaRef.DeclareGlobalNewDelete();
break;
default:
break;
}
}
}
#ifndef NDEBUG
void LookupResult::sanity() const {
assert(ResultKind != NotFound || Decls.size() == 0);
assert(ResultKind != Found || Decls.size() == 1);
assert(ResultKind != FoundOverloaded || Decls.size() > 1 ||
(Decls.size() == 1 &&
isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl())));
assert(ResultKind != FoundUnresolvedValue || sanityCheckUnresolved());
assert(ResultKind != Ambiguous || Decls.size() > 1 ||
(Decls.size() == 1 && Ambiguity == AmbiguousBaseSubobjects));
assert((Paths != NULL) == (ResultKind == Ambiguous &&
(Ambiguity == AmbiguousBaseSubobjectTypes ||
Ambiguity == AmbiguousBaseSubobjects)));
}
#endif
// Necessary because CXXBasePaths is not complete in Sema.h
void LookupResult::deletePaths(CXXBasePaths *Paths) {
delete Paths;
}
/// Resolves the result kind of this lookup.
void LookupResult::resolveKind() {
unsigned N = Decls.size();
// Fast case: no possible ambiguity.
if (N == 0) {
assert(ResultKind == NotFound || ResultKind == NotFoundInCurrentInstantiation);
return;
}
// If there's a single decl, we need to examine it to decide what
// kind of lookup this is.
if (N == 1) {
NamedDecl *D = (*Decls.begin())->getUnderlyingDecl();
if (isa<FunctionTemplateDecl>(D))
ResultKind = FoundOverloaded;
else if (isa<UnresolvedUsingValueDecl>(D))
ResultKind = FoundUnresolvedValue;
return;
}
// Don't do any extra resolution if we've already resolved as ambiguous.
if (ResultKind == Ambiguous) return;
llvm::SmallPtrSet<NamedDecl*, 16> Unique;
llvm::SmallPtrSet<QualType, 16> UniqueTypes;
bool Ambiguous = false;
bool HasTag = false, HasFunction = false, HasNonFunction = false;
bool HasFunctionTemplate = false, HasUnresolved = false;
unsigned UniqueTagIndex = 0;
unsigned I = 0;
while (I < N) {
NamedDecl *D = Decls[I]->getUnderlyingDecl();
D = cast<NamedDecl>(D->getCanonicalDecl());
// Redeclarations of types via typedef can occur both within a scope
// and, through using declarations and directives, across scopes. There is
// no ambiguity if they all refer to the same type, so unique based on the
// canonical type.
if (TypeDecl *TD = dyn_cast<TypeDecl>(D)) {
if (!TD->getDeclContext()->isRecord()) {
QualType T = SemaRef.Context.getTypeDeclType(TD);
if (!UniqueTypes.insert(SemaRef.Context.getCanonicalType(T))) {
// The type is not unique; pull something off the back and continue
// at this index.
Decls[I] = Decls[--N];
continue;
}
}
}
if (!Unique.insert(D)) {
// If it's not unique, pull something off the back (and
// continue at this index).
Decls[I] = Decls[--N];
continue;
}
// Otherwise, do some decl type analysis and then continue.
if (isa<UnresolvedUsingValueDecl>(D)) {
HasUnresolved = true;
} else if (isa<TagDecl>(D)) {
if (HasTag)
Ambiguous = true;
UniqueTagIndex = I;
HasTag = true;
} else if (isa<FunctionTemplateDecl>(D)) {
HasFunction = true;
HasFunctionTemplate = true;
} else if (isa<FunctionDecl>(D)) {
HasFunction = true;
} else {
if (HasNonFunction)
Ambiguous = true;
HasNonFunction = true;
}
I++;
}
// C++ [basic.scope.hiding]p2:
// A class name or enumeration name can be hidden by the name of
// an object, function, or enumerator declared in the same
// scope. If a class or enumeration name and an object, function,
// or enumerator are declared in the same scope (in any order)
// with the same name, the class or enumeration name is hidden
// wherever the object, function, or enumerator name is visible.
// But it's still an error if there are distinct tag types found,
// even if they're not visible. (ref?)
if (HideTags && HasTag && !Ambiguous &&
(HasFunction || HasNonFunction || HasUnresolved))
Decls[UniqueTagIndex] = Decls[--N];
Decls.set_size(N);
if (HasNonFunction && (HasFunction || HasUnresolved))
Ambiguous = true;
if (Ambiguous)
setAmbiguous(LookupResult::AmbiguousReference);
else if (HasUnresolved)
ResultKind = LookupResult::FoundUnresolvedValue;
else if (N > 1 || HasFunctionTemplate)
ResultKind = LookupResult::FoundOverloaded;
else
ResultKind = LookupResult::Found;
}
void LookupResult::addDeclsFromBasePaths(const CXXBasePaths &P) {
CXXBasePaths::const_paths_iterator I, E;
DeclContext::lookup_iterator DI, DE;
for (I = P.begin(), E = P.end(); I != E; ++I)
for (llvm::tie(DI,DE) = I->Decls; DI != DE; ++DI)
addDecl(*DI);
}
void LookupResult::setAmbiguousBaseSubobjects(CXXBasePaths &P) {
Paths = new CXXBasePaths;
Paths->swap(P);
addDeclsFromBasePaths(*Paths);
resolveKind();
setAmbiguous(AmbiguousBaseSubobjects);
}
void LookupResult::setAmbiguousBaseSubobjectTypes(CXXBasePaths &P) {
Paths = new CXXBasePaths;
Paths->swap(P);
addDeclsFromBasePaths(*Paths);
resolveKind();
setAmbiguous(AmbiguousBaseSubobjectTypes);
}
void LookupResult::print(llvm::raw_ostream &Out) {
Out << Decls.size() << " result(s)";
if (isAmbiguous()) Out << ", ambiguous";
if (Paths) Out << ", base paths present";
for (iterator I = begin(), E = end(); I != E; ++I) {
Out << "\n";
(*I)->print(Out, 2);
}
}
/// \brief Lookup a builtin function, when name lookup would otherwise
/// fail.
static bool LookupBuiltin(Sema &S, LookupResult &R) {
Sema::LookupNameKind NameKind = R.getLookupKind();
// If we didn't find a use of this identifier, and if the identifier
// corresponds to a compiler builtin, create the decl object for the builtin
// now, injecting it into translation unit scope, and return it.
if (NameKind == Sema::LookupOrdinaryName ||
NameKind == Sema::LookupRedeclarationWithLinkage) {
IdentifierInfo *II = R.getLookupName().getAsIdentifierInfo();
if (II) {
// If this is a builtin on this (or all) targets, create the decl.
if (unsigned BuiltinID = II->getBuiltinID()) {
// In C++, we don't have any predefined library functions like
// 'malloc'. Instead, we'll just error.
if (S.getLangOptions().CPlusPlus &&
S.Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
return false;
NamedDecl *D = S.LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID,
S.TUScope, R.isForRedeclaration(),
R.getNameLoc());
if (D)
R.addDecl(D);
return (D != NULL);
}
}
}
return false;
}
/// \brief Determine whether we can declare a special member function within
/// the class at this point.
static bool CanDeclareSpecialMemberFunction(ASTContext &Context,
const CXXRecordDecl *Class) {
// Don't do it if the class is invalid.
if (Class->isInvalidDecl())
return false;
// We need to have a definition for the class.
if (!Class->getDefinition() || Class->isDependentContext())
return false;
// We can't be in the middle of defining the class.
if (const RecordType *RecordTy
= Context.getTypeDeclType(Class)->getAs<RecordType>())
return !RecordTy->isBeingDefined();
return false;
}
void Sema::ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class) {
if (!CanDeclareSpecialMemberFunction(Context, Class))
return;
// If the default constructor has not yet been declared, do so now.
if (!Class->hasDeclaredDefaultConstructor())
DeclareImplicitDefaultConstructor(Class);
// If the copy constructor has not yet been declared, do so now.
if (!Class->hasDeclaredCopyConstructor())
DeclareImplicitCopyConstructor(Class);
// If the copy assignment operator has not yet been declared, do so now.
if (!Class->hasDeclaredCopyAssignment())
DeclareImplicitCopyAssignment(Class);
// If the destructor has not yet been declared, do so now.
if (!Class->hasDeclaredDestructor())
DeclareImplicitDestructor(Class);
}
/// \brief Determine whether this is the name of an implicitly-declared
/// special member function.
static bool isImplicitlyDeclaredMemberFunctionName(DeclarationName Name) {
switch (Name.getNameKind()) {
case DeclarationName::CXXConstructorName:
case DeclarationName::CXXDestructorName:
return true;
case DeclarationName::CXXOperatorName:
return Name.getCXXOverloadedOperator() == OO_Equal;
default:
break;
}
return false;
}
/// \brief If there are any implicit member functions with the given name
/// that need to be declared in the given declaration context, do so.
static void DeclareImplicitMemberFunctionsWithName(Sema &S,
DeclarationName Name,
const DeclContext *DC) {
if (!DC)
return;
switch (Name.getNameKind()) {
case DeclarationName::CXXConstructorName:
if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
if (Record->getDefinition() &&
CanDeclareSpecialMemberFunction(S.Context, Record)) {
if (!Record->hasDeclaredDefaultConstructor())
S.DeclareImplicitDefaultConstructor(
const_cast<CXXRecordDecl *>(Record));
if (!Record->hasDeclaredCopyConstructor())
S.DeclareImplicitCopyConstructor(const_cast<CXXRecordDecl *>(Record));
}
break;
case DeclarationName::CXXDestructorName:
if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
if (Record->getDefinition() && !Record->hasDeclaredDestructor() &&
CanDeclareSpecialMemberFunction(S.Context, Record))
S.DeclareImplicitDestructor(const_cast<CXXRecordDecl *>(Record));
break;
case DeclarationName::CXXOperatorName:
if (Name.getCXXOverloadedOperator() != OO_Equal)
break;
if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
if (Record->getDefinition() && !Record->hasDeclaredCopyAssignment() &&
CanDeclareSpecialMemberFunction(S.Context, Record))
S.DeclareImplicitCopyAssignment(const_cast<CXXRecordDecl *>(Record));
break;
default:
break;
}
}
// Adds all qualifying matches for a name within a decl context to the
// given lookup result. Returns true if any matches were found.
static bool LookupDirect(Sema &S, LookupResult &R, const DeclContext *DC) {
bool Found = false;
// Lazily declare C++ special member functions.
if (S.getLangOptions().CPlusPlus)
DeclareImplicitMemberFunctionsWithName(S, R.getLookupName(), DC);
// Perform lookup into this declaration context.
DeclContext::lookup_const_iterator I, E;
for (llvm::tie(I, E) = DC->lookup(R.getLookupName()); I != E; ++I) {
NamedDecl *D = *I;
if (R.isAcceptableDecl(D)) {
R.addDecl(D);
Found = true;
}
}
if (!Found && DC->isTranslationUnit() && LookupBuiltin(S, R))
return true;
if (R.getLookupName().getNameKind()
!= DeclarationName::CXXConversionFunctionName ||
R.getLookupName().getCXXNameType()->isDependentType() ||
!isa<CXXRecordDecl>(DC))
return Found;
// C++ [temp.mem]p6:
// A specialization of a conversion function template is not found by
// name lookup. Instead, any conversion function templates visible in the
// context of the use are considered. [...]
const CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
if (!Record->isDefinition())
return Found;
const UnresolvedSetImpl *Unresolved = Record->getConversionFunctions();
for (UnresolvedSetImpl::iterator U = Unresolved->begin(),
UEnd = Unresolved->end(); U != UEnd; ++U) {
FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(*U);
if (!ConvTemplate)
continue;
// When we're performing lookup for the purposes of redeclaration, just
// add the conversion function template. When we deduce template
// arguments for specializations, we'll end up unifying the return
// type of the new declaration with the type of the function template.
if (R.isForRedeclaration()) {
R.addDecl(ConvTemplate);
Found = true;
continue;
}
// C++ [temp.mem]p6:
// [...] For each such operator, if argument deduction succeeds
// (14.9.2.3), the resulting specialization is used as if found by
// name lookup.
//
// When referencing a conversion function for any purpose other than
// a redeclaration (such that we'll be building an expression with the
// result), perform template argument deduction and place the
// specialization into the result set. We do this to avoid forcing all
// callers to perform special deduction for conversion functions.
TemplateDeductionInfo Info(R.getSema().Context, R.getNameLoc());
FunctionDecl *Specialization = 0;
const FunctionProtoType *ConvProto
= ConvTemplate->getTemplatedDecl()->getType()->getAs<FunctionProtoType>();
assert(ConvProto && "Nonsensical conversion function template type");
// Compute the type of the function that we would expect the conversion
// function to have, if it were to match the name given.
// FIXME: Calling convention!
FunctionType::ExtInfo ConvProtoInfo = ConvProto->getExtInfo();
QualType ExpectedType
= R.getSema().Context.getFunctionType(R.getLookupName().getCXXNameType(),
0, 0, ConvProto->isVariadic(),
ConvProto->getTypeQuals(),
false, false, 0, 0,
ConvProtoInfo.withCallingConv(CC_Default));
// Perform template argument deduction against the type that we would
// expect the function to have.
if (R.getSema().DeduceTemplateArguments(ConvTemplate, 0, ExpectedType,
Specialization, Info)
== Sema::TDK_Success) {
R.addDecl(Specialization);
Found = true;
}
}
return Found;
}
// Performs C++ unqualified lookup into the given file context.
static bool
CppNamespaceLookup(Sema &S, LookupResult &R, ASTContext &Context,
DeclContext *NS, UnqualUsingDirectiveSet &UDirs) {
assert(NS && NS->isFileContext() && "CppNamespaceLookup() requires namespace!");
// Perform direct name lookup into the LookupCtx.
bool Found = LookupDirect(S, R, NS);
// Perform direct name lookup into the namespaces nominated by the
// using directives whose common ancestor is this namespace.
UnqualUsingDirectiveSet::const_iterator UI, UEnd;
llvm::tie(UI, UEnd) = UDirs.getNamespacesFor(NS);
for (; UI != UEnd; ++UI)
if (LookupDirect(S, R, UI->getNominatedNamespace()))
Found = true;
R.resolveKind();
return Found;
}
static bool isNamespaceOrTranslationUnitScope(Scope *S) {
if (DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity()))
return Ctx->isFileContext();
return false;
}
// Find the next outer declaration context from this scope. This
// routine actually returns the semantic outer context, which may
// differ from the lexical context (encoded directly in the Scope
// stack) when we are parsing a member of a class template. In this
// case, the second element of the pair will be true, to indicate that
// name lookup should continue searching in this semantic context when
// it leaves the current template parameter scope.
static std::pair<DeclContext *, bool> findOuterContext(Scope *S) {
DeclContext *DC = static_cast<DeclContext *>(S->getEntity());
DeclContext *Lexical = 0;
for (Scope *OuterS = S->getParent(); OuterS;
OuterS = OuterS->getParent()) {
if (OuterS->getEntity()) {
Lexical = static_cast<DeclContext *>(OuterS->getEntity());
break;
}
}
// C++ [temp.local]p8:
// In the definition of a member of a class template that appears
// outside of the namespace containing the class template
// definition, the name of a template-parameter hides the name of
// a member of this namespace.
//
// Example:
//
// namespace N {
// class C { };
//
// template<class T> class B {
// void f(T);
// };
// }
//
// template<class C> void N::B<C>::f(C) {
// C b; // C is the template parameter, not N::C
// }
//
// In this example, the lexical context we return is the
// TranslationUnit, while the semantic context is the namespace N.
if (!Lexical || !DC || !S->getParent() ||
!S->getParent()->isTemplateParamScope())
return std::make_pair(Lexical, false);
// Find the outermost template parameter scope.
// For the example, this is the scope for the template parameters of
// template<class C>.
Scope *OutermostTemplateScope = S->getParent();
while (OutermostTemplateScope->getParent() &&
OutermostTemplateScope->getParent()->isTemplateParamScope())
OutermostTemplateScope = OutermostTemplateScope->getParent();
// Find the namespace context in which the original scope occurs. In
// the example, this is namespace N.
DeclContext *Semantic = DC;
while (!Semantic->isFileContext())
Semantic = Semantic->getParent();
// Find the declaration context just outside of the template
// parameter scope. This is the context in which the template is
// being lexically declaration (a namespace context). In the
// example, this is the global scope.
if (Lexical->isFileContext() && !Lexical->Equals(Semantic) &&
Lexical->Encloses(Semantic))
return std::make_pair(Semantic, true);
return std::make_pair(Lexical, false);
}
bool Sema::CppLookupName(LookupResult &R, Scope *S) {
assert(getLangOptions().CPlusPlus && "Can perform only C++ lookup");
DeclarationName Name = R.getLookupName();
// If this is the name of an implicitly-declared special member function,
// go through the scope stack to implicitly declare
if (isImplicitlyDeclaredMemberFunctionName(Name)) {
for (Scope *PreS = S; PreS; PreS = PreS->getParent())
if (DeclContext *DC = static_cast<DeclContext *>(PreS->getEntity()))
DeclareImplicitMemberFunctionsWithName(*this, Name, DC);
}
// Implicitly declare member functions with the name we're looking for, if in
// fact we are in a scope where it matters.
Scope *Initial = S;
IdentifierResolver::iterator
I = IdResolver.begin(Name),
IEnd = IdResolver.end();
// First we lookup local scope.
// We don't consider using-directives, as per 7.3.4.p1 [namespace.udir]
// ...During unqualified name lookup (3.4.1), the names appear as if
// they were declared in the nearest enclosing namespace which contains
// both the using-directive and the nominated namespace.
// [Note: in this context, "contains" means "contains directly or
// indirectly".
//
// For example:
// namespace A { int i; }
// void foo() {
// int i;
// {
// using namespace A;
// ++i; // finds local 'i', A::i appears at global scope
// }
// }
//
DeclContext *OutsideOfTemplateParamDC = 0;
for (; S && !isNamespaceOrTranslationUnitScope(S); S = S->getParent()) {
DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity());
// Check whether the IdResolver has anything in this scope.
bool Found = false;
for (; I != IEnd && S->isDeclScope(*I); ++I) {
if (R.isAcceptableDecl(*I)) {
Found = true;
R.addDecl(*I);
}
}
if (Found) {
R.resolveKind();
if (S->isClassScope())
if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(Ctx))
R.setNamingClass(Record);
return true;
}
if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
S->getParent() && !S->getParent()->isTemplateParamScope()) {
// We've just searched the last template parameter scope and
// found nothing, so look into the the contexts between the
// lexical and semantic declaration contexts returned by
// findOuterContext(). This implements the name lookup behavior
// of C++ [temp.local]p8.
Ctx = OutsideOfTemplateParamDC;
OutsideOfTemplateParamDC = 0;
}
if (Ctx) {
DeclContext *OuterCtx;
bool SearchAfterTemplateScope;
llvm::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
if (SearchAfterTemplateScope)
OutsideOfTemplateParamDC = OuterCtx;
for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
// We do not directly look into transparent contexts, since
// those entities will be found in the nearest enclosing
// non-transparent context.
if (Ctx->isTransparentContext())
continue;
// We do not look directly into function or method contexts,
// since all of the local variables and parameters of the
// function/method are present within the Scope.
if (Ctx->isFunctionOrMethod()) {
// If we have an Objective-C instance method, look for ivars
// in the corresponding interface.
if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
if (Method->isInstanceMethod() && Name.getAsIdentifierInfo())
if (ObjCInterfaceDecl *Class = Method->getClassInterface()) {
ObjCInterfaceDecl *ClassDeclared;
if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(
Name.getAsIdentifierInfo(),
ClassDeclared)) {
if (R.isAcceptableDecl(Ivar)) {
R.addDecl(Ivar);
R.resolveKind();
return true;
}
}
}
}
continue;
}
// Perform qualified name lookup into this context.
// FIXME: In some cases, we know that every name that could be found by
// this qualified name lookup will also be on the identifier chain. For
// example, inside a class without any base classes, we never need to
// perform qualified lookup because all of the members are on top of the
// identifier chain.
if (LookupQualifiedName(R, Ctx, /*InUnqualifiedLookup=*/true))
return true;
}
}
}
// Stop if we ran out of scopes.
// FIXME: This really, really shouldn't be happening.
if (!S) return false;
// Collect UsingDirectiveDecls in all scopes, and recursively all
// nominated namespaces by those using-directives.
//
// FIXME: Cache this sorted list in Scope structure, and DeclContext, so we
// don't build it for each lookup!
UnqualUsingDirectiveSet UDirs;
UDirs.visitScopeChain(Initial, S);
UDirs.done();
// Lookup namespace scope, and global scope.
// Unqualified name lookup in C++ requires looking into scopes
// that aren't strictly lexical, and therefore we walk through the
// context as well as walking through the scopes.
for (; S; S = S->getParent()) {
// Check whether the IdResolver has anything in this scope.
bool Found = false;
for (; I != IEnd && S->isDeclScope(*I); ++I) {
if (R.isAcceptableDecl(*I)) {
// We found something. Look for anything else in our scope
// with this same name and in an acceptable identifier
// namespace, so that we can construct an overload set if we
// need to.
Found = true;
R.addDecl(*I);
}
}
if (Found && S->isTemplateParamScope()) {
R.resolveKind();
return true;
}
DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity());
if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
S->getParent() && !S->getParent()->isTemplateParamScope()) {
// We've just searched the last template parameter scope and
// found nothing, so look into the the contexts between the
// lexical and semantic declaration contexts returned by
// findOuterContext(). This implements the name lookup behavior
// of C++ [temp.local]p8.
Ctx = OutsideOfTemplateParamDC;
OutsideOfTemplateParamDC = 0;
}
if (Ctx) {
DeclContext *OuterCtx;
bool SearchAfterTemplateScope;
llvm::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
if (SearchAfterTemplateScope)
OutsideOfTemplateParamDC = OuterCtx;
for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
// We do not directly look into transparent contexts, since
// those entities will be found in the nearest enclosing
// non-transparent context.
if (Ctx->isTransparentContext())
continue;
// If we have a context, and it's not a context stashed in the
// template parameter scope for an out-of-line definition, also
// look into that context.
if (!(Found && S && S->isTemplateParamScope())) {
assert(Ctx->isFileContext() &&
"We should have been looking only at file context here already.");
// Look into context considering using-directives.
if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs))
Found = true;
}
if (Found) {
R.resolveKind();
return true;
}
if (R.isForRedeclaration() && !Ctx->isTransparentContext())
return false;
}
}
if (R.isForRedeclaration() && Ctx && !Ctx->isTransparentContext())
return false;
}
return !R.empty();
}
/// @brief Perform unqualified name lookup starting from a given
/// scope.
///
/// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is
/// used to find names within the current scope. For example, 'x' in
/// @code
/// int x;
/// int f() {
/// return x; // unqualified name look finds 'x' in the global scope
/// }
/// @endcode
///
/// Different lookup criteria can find different names. For example, a
/// particular scope can have both a struct and a function of the same
/// name, and each can be found by certain lookup criteria. For more
/// information about lookup criteria, see the documentation for the
/// class LookupCriteria.
///
/// @param S The scope from which unqualified name lookup will
/// begin. If the lookup criteria permits, name lookup may also search
/// in the parent scopes.
///
/// @param Name The name of the entity that we are searching for.
///
/// @param Loc If provided, the source location where we're performing
/// name lookup. At present, this is only used to produce diagnostics when
/// C library functions (like "malloc") are implicitly declared.
///
/// @returns The result of name lookup, which includes zero or more
/// declarations and possibly additional information used to diagnose
/// ambiguities.
bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) {
DeclarationName Name = R.getLookupName();
if (!Name) return false;
LookupNameKind NameKind = R.getLookupKind();
if (!getLangOptions().CPlusPlus) {
// Unqualified name lookup in C/Objective-C is purely lexical, so
// search in the declarations attached to the name.
if (NameKind == Sema::LookupRedeclarationWithLinkage) {
// Find the nearest non-transparent declaration scope.
while (!(S->getFlags() & Scope::DeclScope) ||
(S->getEntity() &&
static_cast<DeclContext *>(S->getEntity())
->isTransparentContext()))
S = S->getParent();
}
unsigned IDNS = R.getIdentifierNamespace();
// Scan up the scope chain looking for a decl that matches this
// identifier that is in the appropriate namespace. This search
// should not take long, as shadowing of names is uncommon, and
// deep shadowing is extremely uncommon.
bool LeftStartingScope = false;
for (IdentifierResolver::iterator I = IdResolver.begin(Name),
IEnd = IdResolver.end();
I != IEnd; ++I)
if ((*I)->isInIdentifierNamespace(IDNS)) {
if (NameKind == LookupRedeclarationWithLinkage) {
// Determine whether this (or a previous) declaration is
// out-of-scope.
if (!LeftStartingScope && !S->isDeclScope(*I))
LeftStartingScope = true;
// If we found something outside of our starting scope that
// does not have linkage, skip it.
if (LeftStartingScope && !((*I)->hasLinkage()))
continue;
}
R.addDecl(*I);
if ((*I)->getAttr<OverloadableAttr>()) {
// If this declaration has the "overloadable" attribute, we
// might have a set of overloaded functions.
// Figure out what scope the identifier is in.
while (!(S->getFlags() & Scope::DeclScope) ||
!S->isDeclScope(*I))
S = S->getParent();
// Find the last declaration in this scope (with the same
// name, naturally).
IdentifierResolver::iterator LastI = I;
for (++LastI; LastI != IEnd; ++LastI) {
if (!S->isDeclScope(*LastI))
break;
R.addDecl(*LastI);
}
}
R.resolveKind();
return true;
}
} else {
// Perform C++ unqualified name lookup.
if (CppLookupName(R, S))
return true;
}
// If we didn't find a use of this identifier, and if the identifier
// corresponds to a compiler builtin, create the decl object for the builtin
// now, injecting it into translation unit scope, and return it.
if (AllowBuiltinCreation)
return LookupBuiltin(*this, R);
return false;
}
/// @brief Perform qualified name lookup in the namespaces nominated by
/// using directives by the given context.
///
/// C++98 [namespace.qual]p2:
/// Given X::m (where X is a user-declared namespace), or given ::m
/// (where X is the global namespace), let S be the set of all
/// declarations of m in X and in the transitive closure of all
/// namespaces nominated by using-directives in X and its used
/// namespaces, except that using-directives are ignored in any
/// namespace, including X, directly containing one or more
/// declarations of m. No namespace is searched more than once in
/// the lookup of a name. If S is the empty set, the program is
/// ill-formed. Otherwise, if S has exactly one member, or if the
/// context of the reference is a using-declaration
/// (namespace.udecl), S is the required set of declarations of
/// m. Otherwise if the use of m is not one that allows a unique
/// declaration to be chosen from S, the program is ill-formed.
/// C++98 [namespace.qual]p5:
/// During the lookup of a qualified namespace member name, if the
/// lookup finds more than one declaration of the member, and if one
/// declaration introduces a class name or enumeration name and the
/// other declarations either introduce the same object, the same
/// enumerator or a set of functions, the non-type name hides the
/// class or enumeration name if and only if the declarations are
/// from the same namespace; otherwise (the declarations are from
/// different namespaces), the program is ill-formed.
static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R,
DeclContext *StartDC) {
assert(StartDC->isFileContext() && "start context is not a file context");
DeclContext::udir_iterator I = StartDC->using_directives_begin();
DeclContext::udir_iterator E = StartDC->using_directives_end();
if (I == E) return false;
// We have at least added all these contexts to the queue.
llvm::DenseSet<DeclContext*> Visited;
Visited.insert(StartDC);
// We have not yet looked into these namespaces, much less added
// their "using-children" to the queue.
llvm::SmallVector<NamespaceDecl*, 8> Queue;
// We have already looked into the initial namespace; seed the queue
// with its using-children.
for (; I != E; ++I) {
NamespaceDecl *ND = (*I)->getNominatedNamespace()->getOriginalNamespace();
if (Visited.insert(ND).second)
Queue.push_back(ND);
}
// The easiest way to implement the restriction in [namespace.qual]p5
// is to check whether any of the individual results found a tag
// and, if so, to declare an ambiguity if the final result is not
// a tag.
bool FoundTag = false;
bool FoundNonTag = false;
LookupResult LocalR(LookupResult::Temporary, R);
bool Found = false;
while (!Queue.empty()) {
NamespaceDecl *ND = Queue.back();
Queue.pop_back();
// We go through some convolutions here to avoid copying results
// between LookupResults.
bool UseLocal = !R.empty();
LookupResult &DirectR = UseLocal ? LocalR : R;
bool FoundDirect = LookupDirect(S, DirectR, ND);
if (FoundDirect) {
// First do any local hiding.
DirectR.resolveKind();
// If the local result is a tag, remember that.
if (DirectR.isSingleTagDecl())
FoundTag = true;
else
FoundNonTag = true;
// Append the local results to the total results if necessary.
if (UseLocal) {
R.addAllDecls(LocalR);
LocalR.clear();
}
}
// If we find names in this namespace, ignore its using directives.
if (FoundDirect) {
Found = true;
continue;
}
for (llvm::tie(I,E) = ND->getUsingDirectives(); I != E; ++I) {
NamespaceDecl *Nom = (*I)->getNominatedNamespace();
if (Visited.insert(Nom).second)
Queue.push_back(Nom);
}
}
if (Found) {
if (FoundTag && FoundNonTag)
R.setAmbiguousQualifiedTagHiding();
else
R.resolveKind();
}
return Found;
}
/// \brief Callback that looks for any member of a class with the given name.
static bool LookupAnyMember(const CXXBaseSpecifier *Specifier,
CXXBasePath &Path,
void *Name) {
RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
DeclarationName N = DeclarationName::getFromOpaquePtr(Name);
Path.Decls = BaseRecord->lookup(N);
return Path.Decls.first != Path.Decls.second;
}
/// \brief Perform qualified name lookup into a given context.
///
/// Qualified name lookup (C++ [basic.lookup.qual]) is used to find
/// names when the context of those names is explicit specified, e.g.,
/// "std::vector" or "x->member", or as part of unqualified name lookup.
///
/// Different lookup criteria can find different names. For example, a
/// particular scope can have both a struct and a function of the same
/// name, and each can be found by certain lookup criteria. For more
/// information about lookup criteria, see the documentation for the
/// class LookupCriteria.
///
/// \param R captures both the lookup criteria and any lookup results found.
///
/// \param LookupCtx The context in which qualified name lookup will
/// search. If the lookup criteria permits, name lookup may also search
/// in the parent contexts or (for C++ classes) base classes.
///
/// \param InUnqualifiedLookup true if this is qualified name lookup that
/// occurs as part of unqualified name lookup.
///
/// \returns true if lookup succeeded, false if it failed.
bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
bool InUnqualifiedLookup) {
assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context");
if (!R.getLookupName())
return false;
// Make sure that the declaration context is complete.
assert((!isa<TagDecl>(LookupCtx) ||
LookupCtx->isDependentContext() ||
cast<TagDecl>(LookupCtx)->isDefinition() ||
Context.getTypeDeclType(cast<TagDecl>(LookupCtx))->getAs<TagType>()
->isBeingDefined()) &&
"Declaration context must already be complete!");
// Perform qualified name lookup into the LookupCtx.
if (LookupDirect(*this, R, LookupCtx)) {
R.resolveKind();
if (isa<CXXRecordDecl>(LookupCtx))
R.setNamingClass(cast<CXXRecordDecl>(LookupCtx));
return true;
}
// Don't descend into implied contexts for redeclarations.
// C++98 [namespace.qual]p6:
// In a declaration for a namespace member in which the
// declarator-id is a qualified-id, given that the qualified-id
// for the namespace member has the form
// nested-name-specifier unqualified-id
// the unqualified-id shall name a member of the namespace
// designated by the nested-name-specifier.
// See also [class.mfct]p5 and [class.static.data]p2.
if (R.isForRedeclaration())
return false;
// If this is a namespace, look it up in the implied namespaces.
if (LookupCtx->isFileContext())
return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx);
// If this isn't a C++ class, we aren't allowed to look into base
// classes, we're done.
CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx);
if (!LookupRec || !LookupRec->getDefinition())
return false;
// If we're performing qualified name lookup into a dependent class,
// then we are actually looking into a current instantiation. If we have any
// dependent base classes, then we either have to delay lookup until
// template instantiation time (at which point all bases will be available)
// or we have to fail.
if (!InUnqualifiedLookup && LookupRec->isDependentContext() &&
LookupRec->hasAnyDependentBases()) {
R.setNotFoundInCurrentInstantiation();
return false;
}
// Perform lookup into our base classes.
CXXBasePaths Paths;
Paths.setOrigin(LookupRec);
// Look for this member in our base classes
CXXRecordDecl::BaseMatchesCallback *BaseCallback = 0;
switch (R.getLookupKind()) {
case LookupOrdinaryName:
case LookupMemberName:
case LookupRedeclarationWithLinkage:
BaseCallback = &CXXRecordDecl::FindOrdinaryMember;
break;
case LookupTagName:
BaseCallback = &CXXRecordDecl::FindTagMember;
break;
case LookupAnyName:
BaseCallback = &LookupAnyMember;
break;
case LookupUsingDeclName:
// This lookup is for redeclarations only.
case LookupOperatorName:
case LookupNamespaceName:
case LookupObjCProtocolName:
// These lookups will never find a member in a C++ class (or base class).
return false;
case LookupNestedNameSpecifierName:
BaseCallback = &CXXRecordDecl::FindNestedNameSpecifierMember;
break;
}
if (!LookupRec->lookupInBases(BaseCallback,
R.getLookupName().getAsOpaquePtr(), Paths))
return false;
R.setNamingClass(LookupRec);
// C++ [class.member.lookup]p2:
// [...] If the resulting set of declarations are not all from
// sub-objects of the same type, or the set has a nonstatic member
// and includes members from distinct sub-objects, there is an
// ambiguity and the program is ill-formed. Otherwise that set is
// the result of the lookup.
// FIXME: support using declarations!
QualType SubobjectType;
int SubobjectNumber = 0;
AccessSpecifier SubobjectAccess = AS_none;
for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end();
Path != PathEnd; ++Path) {
const CXXBasePathElement &PathElement = Path->back();
// Pick the best (i.e. most permissive i.e. numerically lowest) access
// across all paths.
SubobjectAccess = std::min(SubobjectAccess, Path->Access);
// Determine whether we're looking at a distinct sub-object or not.
if (SubobjectType.isNull()) {
// This is the first subobject we've looked at. Record its type.
SubobjectType = Context.getCanonicalType(PathElement.Base->getType());
SubobjectNumber = PathElement.SubobjectNumber;
} else if (SubobjectType
!= Context.getCanonicalType(PathElement.Base->getType())) {
// We found members of the given name in two subobjects of
// different types. This lookup is ambiguous.
R.setAmbiguousBaseSubobjectTypes(Paths);
return true;
} else if (SubobjectNumber != PathElement.SubobjectNumber) {
// We have a different subobject of the same type.
// C++ [class.member.lookup]p5:
// A static member, a nested type or an enumerator defined in
// a base class T can unambiguously be found even if an object
// has more than one base class subobject of type T.
Decl *FirstDecl = *Path->Decls.first;
if (isa<VarDecl>(FirstDecl) ||
isa<TypeDecl>(FirstDecl) ||
isa<EnumConstantDecl>(FirstDecl))
continue;
if (isa<CXXMethodDecl>(FirstDecl)) {
// Determine whether all of the methods are static.
bool AllMethodsAreStatic = true;
for (DeclContext::lookup_iterator Func = Path->Decls.first;
Func != Path->Decls.second; ++Func) {
if (!isa<CXXMethodDecl>(*Func)) {
assert(isa<TagDecl>(*Func) && "Non-function must be a tag decl");
break;
}
if (!cast<CXXMethodDecl>(*Func)->isStatic()) {
AllMethodsAreStatic = false;
break;
}
}
if (AllMethodsAreStatic)
continue;
}
// We have found a nonstatic member name in multiple, distinct
// subobjects. Name lookup is ambiguous.
R.setAmbiguousBaseSubobjects(Paths);
return true;
}
}
// Lookup in a base class succeeded; return these results.
DeclContext::lookup_iterator I, E;
for (llvm::tie(I,E) = Paths.front().Decls; I != E; ++I) {
NamedDecl *D = *I;
AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess,
D->getAccess());
R.addDecl(D, AS);
}
R.resolveKind();
return true;
}
/// @brief Performs name lookup for a name that was parsed in the
/// source code, and may contain a C++ scope specifier.
///
/// This routine is a convenience routine meant to be called from
/// contexts that receive a name and an optional C++ scope specifier
/// (e.g., "N::M::x"). It will then perform either qualified or
/// unqualified name lookup (with LookupQualifiedName or LookupName,
/// respectively) on the given name and return those results.
///
/// @param S The scope from which unqualified name lookup will
/// begin.
///
/// @param SS An optional C++ scope-specifier, e.g., "::N::M".
///
/// @param Name The name of the entity that name lookup will
/// search for.
///
/// @param Loc If provided, the source location where we're performing
/// name lookup. At present, this is only used to produce diagnostics when
/// C library functions (like "malloc") are implicitly declared.
///
/// @param EnteringContext Indicates whether we are going to enter the
/// context of the scope-specifier SS (if present).
///
/// @returns True if any decls were found (but possibly ambiguous)
bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
bool AllowBuiltinCreation, bool EnteringContext) {
if (SS && SS->isInvalid()) {
// When the scope specifier is invalid, don't even look for
// anything.
return false;
}
if (SS && SS->isSet()) {
if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) {
// We have resolved the scope specifier to a particular declaration
// contex, and will perform name lookup in that context.
if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC))
return false;
R.setContextRange(SS->getRange());
return LookupQualifiedName(R, DC);
}
// We could not resolve the scope specified to a specific declaration
// context, which means that SS refers to an unknown specialization.
// Name lookup can't find anything in this case.
return false;
}
// Perform unqualified name lookup starting in the given scope.
return LookupName(R, S, AllowBuiltinCreation);
}
/// @brief Produce a diagnostic describing the ambiguity that resulted
/// from name lookup.
///
/// @param Result The ambiguous name lookup result.
///
/// @param Name The name of the entity that name lookup was
/// searching for.
///
/// @param NameLoc The location of the name within the source code.
///
/// @param LookupRange A source range that provides more
/// source-location information concerning the lookup itself. For
/// example, this range might highlight a nested-name-specifier that
/// precedes the name.
///
/// @returns true
bool Sema::DiagnoseAmbiguousLookup(LookupResult &Result) {
assert(Result.isAmbiguous() && "Lookup result must be ambiguous");
DeclarationName Name = Result.getLookupName();
SourceLocation NameLoc = Result.getNameLoc();
SourceRange LookupRange = Result.getContextRange();
switch (Result.getAmbiguityKind()) {
case LookupResult::AmbiguousBaseSubobjects: {
CXXBasePaths *Paths = Result.getBasePaths();
QualType SubobjectType = Paths->front().back().Base->getType();
Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects)
<< Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths)
<< LookupRange;
DeclContext::lookup_iterator Found = Paths->front().Decls.first;
while (isa<CXXMethodDecl>(*Found) &&
cast<CXXMethodDecl>(*Found)->isStatic())
++Found;
Diag((*Found)->getLocation(), diag::note_ambiguous_member_found);
return true;
}
case LookupResult::AmbiguousBaseSubobjectTypes: {
Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types)
<< Name << LookupRange;
CXXBasePaths *Paths = Result.getBasePaths();
std::set<Decl *> DeclsPrinted;
for (CXXBasePaths::paths_iterator Path = Paths->begin(),
PathEnd = Paths->end();
Path != PathEnd; ++Path) {
Decl *D = *Path->Decls.first;
if (DeclsPrinted.insert(D).second)
Diag(D->getLocation(), diag::note_ambiguous_member_found);
}
return true;
}
case LookupResult::AmbiguousTagHiding: {
Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange;
llvm::SmallPtrSet<NamedDecl*,8> TagDecls;
LookupResult::iterator DI, DE = Result.end();
for (DI = Result.begin(); DI != DE; ++DI)
if (TagDecl *TD = dyn_cast<TagDecl>(*DI)) {
TagDecls.insert(TD);
Diag(TD->getLocation(), diag::note_hidden_tag);
}
for (DI = Result.begin(); DI != DE; ++DI)
if (!isa<TagDecl>(*DI))
Diag((*DI)->getLocation(), diag::note_hiding_object);
// For recovery purposes, go ahead and implement the hiding.
LookupResult::Filter F = Result.makeFilter();
while (F.hasNext()) {
if (TagDecls.count(F.next()))
F.erase();
}
F.done();
return true;
}
case LookupResult::AmbiguousReference: {
Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange;
LookupResult::iterator DI = Result.begin(), DE = Result.end();
for (; DI != DE; ++DI)
Diag((*DI)->getLocation(), diag::note_ambiguous_candidate) << *DI;
return true;
}
}
llvm_unreachable("unknown ambiguity kind");
return true;
}
namespace {
struct AssociatedLookup {
AssociatedLookup(Sema &S,
Sema::AssociatedNamespaceSet &Namespaces,
Sema::AssociatedClassSet &Classes)
: S(S), Namespaces(Namespaces), Classes(Classes) {
}
Sema &S;
Sema::AssociatedNamespaceSet &Namespaces;
Sema::AssociatedClassSet &Classes;
};
}
static void
addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T);
static void CollectEnclosingNamespace(Sema::AssociatedNamespaceSet &Namespaces,
DeclContext *Ctx) {
// Add the associated namespace for this class.
// We don't use DeclContext::getEnclosingNamespaceContext() as this may
// be a locally scoped record.
while (Ctx->isRecord() || Ctx->isTransparentContext())
Ctx = Ctx->getParent();
if (Ctx->isFileContext())
Namespaces.insert(Ctx->getPrimaryContext());
}
// \brief Add the associated classes and namespaces for argument-dependent
// lookup that involves a template argument (C++ [basic.lookup.koenig]p2).
static void
addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
const TemplateArgument &Arg) {
// C++ [basic.lookup.koenig]p2, last bullet:
// -- [...] ;
switch (Arg.getKind()) {
case TemplateArgument::Null:
break;
case TemplateArgument::Type:
// [...] the namespaces and classes associated with the types of the
// template arguments provided for template type parameters (excluding
// template template parameters)
addAssociatedClassesAndNamespaces(Result, Arg.getAsType());
break;
case TemplateArgument::Template: {
// [...] the namespaces in which any template template arguments are
// defined; and the classes in which any member templates used as
// template template arguments are defined.
TemplateName Template = Arg.getAsTemplate();
if (ClassTemplateDecl *ClassTemplate
= dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) {
DeclContext *Ctx = ClassTemplate->getDeclContext();
if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
Result.Classes.insert(EnclosingClass);
// Add the associated namespace for this class.
CollectEnclosingNamespace(Result.Namespaces, Ctx);
}
break;
}
case TemplateArgument::Declaration:
case TemplateArgument::Integral:
case TemplateArgument::Expression:
// [Note: non-type template arguments do not contribute to the set of
// associated namespaces. ]
break;
case TemplateArgument::Pack:
for (TemplateArgument::pack_iterator P = Arg.pack_begin(),
PEnd = Arg.pack_end();
P != PEnd; ++P)
addAssociatedClassesAndNamespaces(Result, *P);
break;
}
}
// \brief Add the associated classes and namespaces for
// argument-dependent lookup with an argument of class type
// (C++ [basic.lookup.koenig]p2).
static void
addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
CXXRecordDecl *Class) {
// Just silently ignore anything whose name is __va_list_tag.
if (Class->getDeclName() == Result.S.VAListTagName)
return;
// C++ [basic.lookup.koenig]p2:
// [...]
// -- If T is a class type (including unions), its associated
// classes are: the class itself; the class of which it is a
// member, if any; and its direct and indirect base
// classes. Its associated namespaces are the namespaces in
// which its associated classes are defined.
// Add the class of which it is a member, if any.
DeclContext *Ctx = Class->getDeclContext();
if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
Result.Classes.insert(EnclosingClass);
// Add the associated namespace for this class.
CollectEnclosingNamespace(Result.Namespaces, Ctx);
// Add the class itself. If we've already seen this class, we don't
// need to visit base classes.
if (!Result.Classes.insert(Class))
return;
// -- If T is a template-id, its associated namespaces and classes are
// the namespace in which the template is defined; for member
// templates, the member templates class; the namespaces and classes
// associated with the types of the template arguments provided for
// template type parameters (excluding template template parameters); the
// namespaces in which any template template arguments are defined; and
// the classes in which any member templates used as template template
// arguments are defined. [Note: non-type template arguments do not
// contribute to the set of associated namespaces. ]
if (ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(Class)) {
DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext();
if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
Result.Classes.insert(EnclosingClass);
// Add the associated namespace for this class.
CollectEnclosingNamespace(Result.Namespaces, Ctx);
const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]);
}
// Only recurse into base classes for complete types.
if (!Class->hasDefinition()) {
// FIXME: we might need to instantiate templates here
return;
}
// Add direct and indirect base classes along with their associated
// namespaces.
llvm::SmallVector<CXXRecordDecl *, 32> Bases;
Bases.push_back(Class);
while (!Bases.empty()) {
// Pop this class off the stack.
Class = Bases.back();
Bases.pop_back();
// Visit the base classes.
for (CXXRecordDecl::base_class_iterator Base = Class->bases_begin(),
BaseEnd = Class->bases_end();
Base != BaseEnd; ++Base) {
const RecordType *BaseType = Base->getType()->getAs<RecordType>();
// In dependent contexts, we do ADL twice, and the first time around,
// the base type might be a dependent TemplateSpecializationType, or a
// TemplateTypeParmType. If that happens, simply ignore it.
// FIXME: If we want to support export, we probably need to add the
// namespace of the template in a TemplateSpecializationType, or even
// the classes and namespaces of known non-dependent arguments.
if (!BaseType)
continue;
CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl());
if (Result.Classes.insert(BaseDecl)) {
// Find the associated namespace for this base class.
DeclContext *BaseCtx = BaseDecl->getDeclContext();
CollectEnclosingNamespace(Result.Namespaces, BaseCtx);
// Make sure we visit the bases of this base class.
if (BaseDecl->bases_begin() != BaseDecl->bases_end())
Bases.push_back(BaseDecl);
}
}
}
}
// \brief Add the associated classes and namespaces for
// argument-dependent lookup with an argument of type T
// (C++ [basic.lookup.koenig]p2).
static void
addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) {
// C++ [basic.lookup.koenig]p2:
//
// For each argument type T in the function call, there is a set
// of zero or more associated namespaces and a set of zero or more
// associated classes to be considered. The sets of namespaces and
// classes is determined entirely by the types of the function
// arguments (and the namespace of any template template
// argument). Typedef names and using-declarations used to specify
// the types do not contribute to this set. The sets of namespaces
// and classes are determined in the following way:
llvm::SmallVector<const Type *, 16> Queue;
const Type *T = Ty->getCanonicalTypeInternal().getTypePtr();
while (true) {
switch (T->getTypeClass()) {
#define TYPE(Class, Base)
#define DEPENDENT_TYPE(Class, Base) case Type::Class:
#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
#define ABSTRACT_TYPE(Class, Base)
#include "clang/AST/TypeNodes.def"
// T is canonical. We can also ignore dependent types because
// we don't need to do ADL at the definition point, but if we
// wanted to implement template export (or if we find some other
// use for associated classes and namespaces...) this would be
// wrong.
break;
// -- If T is a pointer to U or an array of U, its associated
// namespaces and classes are those associated with U.
case Type::Pointer:
T = cast<PointerType>(T)->getPointeeType().getTypePtr();
continue;
case Type::ConstantArray:
case Type::IncompleteArray:
case Type::VariableArray:
T = cast<ArrayType>(T)->getElementType().getTypePtr();
continue;
// -- If T is a fundamental type, its associated sets of
// namespaces and classes are both empty.
case Type::Builtin:
break;
// -- If T is a class type (including unions), its associated
// classes are: the class itself; the class of which it is a
// member, if any; and its direct and indirect base
// classes. Its associated namespaces are the namespaces in
// which its associated classes are defined.
case Type::Record: {
CXXRecordDecl *Class
= cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl());
addAssociatedClassesAndNamespaces(Result, Class);
break;
}
// -- If T is an enumeration type, its associated namespace is
// the namespace in which it is defined. If it is class
// member, its associated class is the members class; else
// it has no associated class.
case Type::Enum: {
EnumDecl *Enum = cast<EnumType>(T)->getDecl();
DeclContext *Ctx = Enum->getDeclContext();
if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
Result.Classes.insert(EnclosingClass);
// Add the associated namespace for this class.
CollectEnclosingNamespace(Result.Namespaces, Ctx);
break;
}
// -- If T is a function type, its associated namespaces and
// classes are those associated with the function parameter
// types and those associated with the return type.
case Type::FunctionProto: {
const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
for (FunctionProtoType::arg_type_iterator Arg = Proto->arg_type_begin(),
ArgEnd = Proto->arg_type_end();
Arg != ArgEnd; ++Arg)
Queue.push_back(Arg->getTypePtr());
// fallthrough
}
case Type::FunctionNoProto: {
const FunctionType *FnType = cast<FunctionType>(T);
T = FnType->getResultType().getTypePtr();
continue;
}
// -- If T is a pointer to a member function of a class X, its
// associated namespaces and classes are those associated
// with the function parameter types and return type,
// together with those associated with X.
//
// -- If T is a pointer to a data member of class X, its
// associated namespaces and classes are those associated
// with the member type together with those associated with
// X.
case Type::MemberPointer: {
const MemberPointerType *MemberPtr = cast<MemberPointerType>(T);
// Queue up the class type into which this points.
Queue.push_back(MemberPtr->getClass());
// And directly continue with the pointee type.
T = MemberPtr->getPointeeType().getTypePtr();
continue;
}
// As an extension, treat this like a normal pointer.
case Type::BlockPointer:
T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr();
continue;
// References aren't covered by the standard, but that's such an
// obvious defect that we cover them anyway.
case Type::LValueReference:
case Type::RValueReference:
T = cast<ReferenceType>(T)->getPointeeType().getTypePtr();
continue;
// These are fundamental types.
case Type::Vector:
case Type::ExtVector:
case Type::Complex:
break;
// These are ignored by ADL.
case Type::ObjCObject:
case Type::ObjCInterface:
case Type::ObjCObjectPointer:
break;
}
if (Queue.empty()) break;
T = Queue.back();
Queue.pop_back();
}
}
/// \brief Find the associated classes and namespaces for
/// argument-dependent lookup for a call with the given set of
/// arguments.
///
/// This routine computes the sets of associated classes and associated
/// namespaces searched by argument-dependent lookup
/// (C++ [basic.lookup.argdep]) for a given set of arguments.
void
Sema::FindAssociatedClassesAndNamespaces(Expr **Args, unsigned NumArgs,
AssociatedNamespaceSet &AssociatedNamespaces,
AssociatedClassSet &AssociatedClasses) {
AssociatedNamespaces.clear();
AssociatedClasses.clear();
AssociatedLookup Result(*this, AssociatedNamespaces, AssociatedClasses);
// C++ [basic.lookup.koenig]p2:
// For each argument type T in the function call, there is a set
// of zero or more associated namespaces and a set of zero or more
// associated classes to be considered. The sets of namespaces and
// classes is determined entirely by the types of the function
// arguments (and the namespace of any template template
// argument).
for (unsigned ArgIdx = 0; ArgIdx != NumArgs; ++ArgIdx) {
Expr *Arg = Args[ArgIdx];
if (Arg->getType() != Context.OverloadTy) {
addAssociatedClassesAndNamespaces(Result, Arg->getType());
continue;
}
// [...] In addition, if the argument is the name or address of a
// set of overloaded functions and/or function templates, its
// associated classes and namespaces are the union of those
// associated with each of the members of the set: the namespace
// in which the function or function template is defined and the
// classes and namespaces associated with its (non-dependent)
// parameter types and return type.
Arg = Arg->IgnoreParens();
if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg))
if (unaryOp->getOpcode() == UO_AddrOf)
Arg = unaryOp->getSubExpr();
UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg);
if (!ULE) continue;
for (UnresolvedSetIterator I = ULE->decls_begin(), E = ULE->decls_end();
I != E; ++I) {
// Look through any using declarations to find the underlying function.
NamedDecl *Fn = (*I)->getUnderlyingDecl();
FunctionDecl *FDecl = dyn_cast<FunctionDecl>(Fn);
if (!FDecl)
FDecl = cast<FunctionTemplateDecl>(Fn)->getTemplatedDecl();
// Add the classes and namespaces associated with the parameter
// types and return type of this function.
addAssociatedClassesAndNamespaces(Result, FDecl->getType());
}
}
}
/// IsAcceptableNonMemberOperatorCandidate - Determine whether Fn is
/// an acceptable non-member overloaded operator for a call whose
/// arguments have types T1 (and, if non-empty, T2). This routine
/// implements the check in C++ [over.match.oper]p3b2 concerning
/// enumeration types.
static bool
IsAcceptableNonMemberOperatorCandidate(FunctionDecl *Fn,
QualType T1, QualType T2,
ASTContext &Context) {
if (T1->isDependentType() || (!T2.isNull() && T2->isDependentType()))
return true;
if (T1->isRecordType() || (!T2.isNull() && T2->isRecordType()))
return true;
const FunctionProtoType *Proto = Fn->getType()->getAs<FunctionProtoType>();
if (Proto->getNumArgs() < 1)
return false;
if (T1->isEnumeralType()) {
QualType ArgType = Proto->getArgType(0).getNonReferenceType();
if (Context.hasSameUnqualifiedType(T1, ArgType))
return true;
}
if (Proto->getNumArgs() < 2)
return false;
if (!T2.isNull() && T2->isEnumeralType()) {
QualType ArgType = Proto->getArgType(1).getNonReferenceType();
if (Context.hasSameUnqualifiedType(T2, ArgType))
return true;
}
return false;
}
NamedDecl *Sema::LookupSingleName(Scope *S, DeclarationName Name,
SourceLocation Loc,
LookupNameKind NameKind,
RedeclarationKind Redecl) {
LookupResult R(*this, Name, Loc, NameKind, Redecl);
LookupName(R, S);
return R.getAsSingle<NamedDecl>();
}
/// \brief Find the protocol with the given name, if any.
ObjCProtocolDecl *Sema::LookupProtocol(IdentifierInfo *II,
SourceLocation IdLoc) {
Decl *D = LookupSingleName(TUScope, II, IdLoc,
LookupObjCProtocolName);
return cast_or_null<ObjCProtocolDecl>(D);
}
void Sema::LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S,
QualType T1, QualType T2,
UnresolvedSetImpl &Functions) {
// C++ [over.match.oper]p3:
// -- The set of non-member candidates is the result of the
// unqualified lookup of operator@ in the context of the
// expression according to the usual rules for name lookup in
// unqualified function calls (3.4.2) except that all member
// functions are ignored. However, if no operand has a class
// type, only those non-member functions in the lookup set
// that have a first parameter of type T1 or "reference to
// (possibly cv-qualified) T1", when T1 is an enumeration
// type, or (if there is a right operand) a second parameter
// of type T2 or "reference to (possibly cv-qualified) T2",
// when T2 is an enumeration type, are candidate functions.
DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName);
LookupName(Operators, S);
assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous");
if (Operators.empty())
return;
for (LookupResult::iterator Op = Operators.begin(), OpEnd = Operators.end();
Op != OpEnd; ++Op) {
NamedDecl *Found = (*Op)->getUnderlyingDecl();
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Found)) {
if (IsAcceptableNonMemberOperatorCandidate(FD, T1, T2, Context))
Functions.addDecl(*Op, Op.getAccess()); // FIXME: canonical FD
} else if (FunctionTemplateDecl *FunTmpl
= dyn_cast<FunctionTemplateDecl>(Found)) {
// FIXME: friend operators?
// FIXME: do we need to check IsAcceptableNonMemberOperatorCandidate,
// later?
if (!FunTmpl->getDeclContext()->isRecord())
Functions.addDecl(*Op, Op.getAccess());
}
}
}
/// \brief Look up the constructors for the given class.
DeclContext::lookup_result Sema::LookupConstructors(CXXRecordDecl *Class) {
// If the copy constructor has not yet been declared, do so now.
if (CanDeclareSpecialMemberFunction(Context, Class)) {
if (!Class->hasDeclaredDefaultConstructor())
DeclareImplicitDefaultConstructor(Class);
if (!Class->hasDeclaredCopyConstructor())
DeclareImplicitCopyConstructor(Class);
}
CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class));
DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(T);
return Class->lookup(Name);
}
/// \brief Look for the destructor of the given class.
///
/// During semantic analysis, this routine should be used in lieu of
/// CXXRecordDecl::getDestructor().
///
/// \returns The destructor for this class.
CXXDestructorDecl *Sema::LookupDestructor(CXXRecordDecl *Class) {
// If the destructor has not yet been declared, do so now.
if (CanDeclareSpecialMemberFunction(Context, Class) &&
!Class->hasDeclaredDestructor())
DeclareImplicitDestructor(Class);
return Class->getDestructor();
}
void ADLResult::insert(NamedDecl *New) {
NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())];
// If we haven't yet seen a decl for this key, or the last decl
// was exactly this one, we're done.
if (Old == 0 || Old == New) {
Old = New;
return;
}
// Otherwise, decide which is a more recent redeclaration.
FunctionDecl *OldFD, *NewFD;
if (isa<FunctionTemplateDecl>(New)) {
OldFD = cast<FunctionTemplateDecl>(Old)->getTemplatedDecl();
NewFD = cast<FunctionTemplateDecl>(New)->getTemplatedDecl();
} else {
OldFD = cast<FunctionDecl>(Old);
NewFD = cast<FunctionDecl>(New);
}
FunctionDecl *Cursor = NewFD;
while (true) {
Cursor = Cursor->getPreviousDeclaration();
// If we got to the end without finding OldFD, OldFD is the newer
// declaration; leave things as they are.
if (!Cursor) return;
// If we do find OldFD, then NewFD is newer.
if (Cursor == OldFD) break;
// Otherwise, keep looking.
}
Old = New;
}
void Sema::ArgumentDependentLookup(DeclarationName Name, bool Operator,
Expr **Args, unsigned NumArgs,
ADLResult &Result) {
// Find all of the associated namespaces and classes based on the
// arguments we have.
AssociatedNamespaceSet AssociatedNamespaces;
AssociatedClassSet AssociatedClasses;
FindAssociatedClassesAndNamespaces(Args, NumArgs,
AssociatedNamespaces,
AssociatedClasses);
QualType T1, T2;
if (Operator) {
T1 = Args[0]->getType();
if (NumArgs >= 2)
T2 = Args[1]->getType();
}
// C++ [basic.lookup.argdep]p3:
// Let X be the lookup set produced by unqualified lookup (3.4.1)
// and let Y be the lookup set produced by argument dependent
// lookup (defined as follows). If X contains [...] then Y is
// empty. Otherwise Y is the set of declarations found in the
// namespaces associated with the argument types as described
// below. The set of declarations found by the lookup of the name
// is the union of X and Y.
//
// Here, we compute Y and add its members to the overloaded
// candidate set.
for (AssociatedNamespaceSet::iterator NS = AssociatedNamespaces.begin(),
NSEnd = AssociatedNamespaces.end();
NS != NSEnd; ++NS) {
// When considering an associated namespace, the lookup is the
// same as the lookup performed when the associated namespace is
// used as a qualifier (3.4.3.2) except that:
//
// -- Any using-directives in the associated namespace are
// ignored.
//
// -- Any namespace-scope friend functions declared in
// associated classes are visible within their respective
// namespaces even if they are not visible during an ordinary
// lookup (11.4).
DeclContext::lookup_iterator I, E;
for (llvm::tie(I, E) = (*NS)->lookup(Name); I != E; ++I) {
NamedDecl *D = *I;
// If the only declaration here is an ordinary friend, consider
// it only if it was declared in an associated classes.
if (D->getIdentifierNamespace() == Decl::IDNS_OrdinaryFriend) {
DeclContext *LexDC = D->getLexicalDeclContext();
if (!AssociatedClasses.count(cast<CXXRecordDecl>(LexDC)))
continue;
}
if (isa<UsingShadowDecl>(D))
D = cast<UsingShadowDecl>(D)->getTargetDecl();
if (isa<FunctionDecl>(D)) {
if (Operator &&
!IsAcceptableNonMemberOperatorCandidate(cast<FunctionDecl>(D),
T1, T2, Context))
continue;
} else if (!isa<FunctionTemplateDecl>(D))
continue;
Result.insert(D);
}
}
}
//----------------------------------------------------------------------------
// Search for all visible declarations.
//----------------------------------------------------------------------------
VisibleDeclConsumer::~VisibleDeclConsumer() { }
namespace {
class ShadowContextRAII;
class VisibleDeclsRecord {
public:
/// \brief An entry in the shadow map, which is optimized to store a
/// single declaration (the common case) but can also store a list
/// of declarations.
class ShadowMapEntry {
typedef llvm::SmallVector<NamedDecl *, 4> DeclVector;
/// \brief Contains either the solitary NamedDecl * or a vector
/// of declarations.
llvm::PointerUnion<NamedDecl *, DeclVector*> DeclOrVector;
public:
ShadowMapEntry() : DeclOrVector() { }
void Add(NamedDecl *ND);
void Destroy();
// Iteration.
typedef NamedDecl **iterator;
iterator begin();
iterator end();
};
private:
/// \brief A mapping from declaration names to the declarations that have
/// this name within a particular scope.
typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap;
/// \brief A list of shadow maps, which is used to model name hiding.
std::list<ShadowMap> ShadowMaps;
/// \brief The declaration contexts we have already visited.
llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts;
friend class ShadowContextRAII;
public:
/// \brief Determine whether we have already visited this context
/// (and, if not, note that we are going to visit that context now).
bool visitedContext(DeclContext *Ctx) {
return !VisitedContexts.insert(Ctx);
}
bool alreadyVisitedContext(DeclContext *Ctx) {
return VisitedContexts.count(Ctx);
}
/// \brief Determine whether the given declaration is hidden in the
/// current scope.
///
/// \returns the declaration that hides the given declaration, or
/// NULL if no such declaration exists.
NamedDecl *checkHidden(NamedDecl *ND);
/// \brief Add a declaration to the current shadow map.
void add(NamedDecl *ND) { ShadowMaps.back()[ND->getDeclName()].Add(ND); }
};
/// \brief RAII object that records when we've entered a shadow context.
class ShadowContextRAII {
VisibleDeclsRecord &Visible;
typedef VisibleDeclsRecord::ShadowMap ShadowMap;
public:
ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) {
Visible.ShadowMaps.push_back(ShadowMap());
}
~ShadowContextRAII() {
for (ShadowMap::iterator E = Visible.ShadowMaps.back().begin(),
EEnd = Visible.ShadowMaps.back().end();
E != EEnd;
++E)
E->second.Destroy();
Visible.ShadowMaps.pop_back();
}
};
} // end anonymous namespace
void VisibleDeclsRecord::ShadowMapEntry::Add(NamedDecl *ND) {
if (DeclOrVector.isNull()) {
// 0 - > 1 elements: just set the single element information.
DeclOrVector = ND;
return;
}
if (NamedDecl *PrevND = DeclOrVector.dyn_cast<NamedDecl *>()) {
// 1 -> 2 elements: create the vector of results and push in the
// existing declaration.
DeclVector *Vec = new DeclVector;
Vec->push_back(PrevND);
DeclOrVector = Vec;
}
// Add the new element to the end of the vector.
DeclOrVector.get<DeclVector*>()->push_back(ND);
}
void VisibleDeclsRecord::ShadowMapEntry::Destroy() {
if (DeclVector *Vec = DeclOrVector.dyn_cast<DeclVector *>()) {
delete Vec;
DeclOrVector = ((NamedDecl *)0);
}
}
VisibleDeclsRecord::ShadowMapEntry::iterator
VisibleDeclsRecord::ShadowMapEntry::begin() {
if (DeclOrVector.isNull())
return 0;
if (DeclOrVector.dyn_cast<NamedDecl *>())
return &reinterpret_cast<NamedDecl*&>(DeclOrVector);
return DeclOrVector.get<DeclVector *>()->begin();
}
VisibleDeclsRecord::ShadowMapEntry::iterator
VisibleDeclsRecord::ShadowMapEntry::end() {
if (DeclOrVector.isNull())
return 0;
if (DeclOrVector.dyn_cast<NamedDecl *>())
return &reinterpret_cast<NamedDecl*&>(DeclOrVector) + 1;
return DeclOrVector.get<DeclVector *>()->end();
}
NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) {
// Look through using declarations.
ND = ND->getUnderlyingDecl();
unsigned IDNS = ND->getIdentifierNamespace();
std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin();
for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend();
SM != SMEnd; ++SM) {
ShadowMap::iterator Pos = SM->find(ND->getDeclName());
if (Pos == SM->end())
continue;
for (ShadowMapEntry::iterator I = Pos->second.begin(),
IEnd = Pos->second.end();
I != IEnd; ++I) {
// A tag declaration does not hide a non-tag declaration.
if ((*I)->hasTagIdentifierNamespace() &&
(IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary |
Decl::IDNS_ObjCProtocol)))
continue;
// Protocols are in distinct namespaces from everything else.
if ((((*I)->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol)
|| (IDNS & Decl::IDNS_ObjCProtocol)) &&
(*I)->getIdentifierNamespace() != IDNS)
continue;
// Functions and function templates in the same scope overload
// rather than hide. FIXME: Look for hiding based on function
// signatures!
if ((*I)->isFunctionOrFunctionTemplate() &&
ND->isFunctionOrFunctionTemplate() &&
SM == ShadowMaps.rbegin())
continue;
// We've found a declaration that hides this one.
return *I;
}
}
return 0;
}
static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
bool QualifiedNameLookup,
bool InBaseClass,
VisibleDeclConsumer &Consumer,
VisibleDeclsRecord &Visited) {
if (!Ctx)
return;
// Make sure we don't visit the same context twice.
if (Visited.visitedContext(Ctx->getPrimaryContext()))
return;
if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx))
Result.getSema().ForceDeclarationOfImplicitMembers(Class);
// Enumerate all of the results in this context.
for (DeclContext *CurCtx = Ctx->getPrimaryContext(); CurCtx;
CurCtx = CurCtx->getNextContext()) {
for (DeclContext::decl_iterator D = CurCtx->decls_begin(),
DEnd = CurCtx->decls_end();
D != DEnd; ++D) {
if (NamedDecl *ND = dyn_cast<NamedDecl>(*D))
if (Result.isAcceptableDecl(ND)) {
Consumer.FoundDecl(ND, Visited.checkHidden(ND), InBaseClass);
Visited.add(ND);
}
// Visit transparent contexts inside this context.
if (DeclContext *InnerCtx = dyn_cast<DeclContext>(*D)) {
if (InnerCtx->isTransparentContext())
LookupVisibleDecls(InnerCtx, Result, QualifiedNameLookup, InBaseClass,
Consumer, Visited);
}
}
}
// Traverse using directives for qualified name lookup.
if (QualifiedNameLookup) {
ShadowContextRAII Shadow(Visited);
DeclContext::udir_iterator I, E;
for (llvm::tie(I, E) = Ctx->getUsingDirectives(); I != E; ++I) {
LookupVisibleDecls((*I)->getNominatedNamespace(), Result,
QualifiedNameLookup, InBaseClass, Consumer, Visited);
}
}
// Traverse the contexts of inherited C++ classes.
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
if (!Record->hasDefinition())
return;
for (CXXRecordDecl::base_class_iterator B = Record->bases_begin(),
BEnd = Record->bases_end();
B != BEnd; ++B) {
QualType BaseType = B->getType();
// Don't look into dependent bases, because name lookup can't look
// there anyway.
if (BaseType->isDependentType())
continue;
const RecordType *Record = BaseType->getAs<RecordType>();
if (!Record)
continue;
// FIXME: It would be nice to be able to determine whether referencing
// a particular member would be ambiguous. For example, given
//
// struct A { int member; };
// struct B { int member; };
// struct C : A, B { };
//
// void f(C *c) { c->### }
//
// accessing 'member' would result in an ambiguity. However, we
// could be smart enough to qualify the member with the base
// class, e.g.,
//
// c->B::member
//
// or
//
// c->A::member
// Find results in this base class (and its bases).
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(Record->getDecl(), Result, QualifiedNameLookup,
true, Consumer, Visited);
}
}
// Traverse the contexts of Objective-C classes.
if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) {
// Traverse categories.
for (ObjCCategoryDecl *Category = IFace->getCategoryList();
Category; Category = Category->getNextClassCategory()) {
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(Category, Result, QualifiedNameLookup, false,
Consumer, Visited);
}
// Traverse protocols.
for (ObjCInterfaceDecl::protocol_iterator I = IFace->protocol_begin(),
E = IFace->protocol_end(); I != E; ++I) {
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer,
Visited);
}
// Traverse the superclass.
if (IFace->getSuperClass()) {
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
true, Consumer, Visited);
}
// If there is an implementation, traverse it. We do this to find
// synthesized ivars.
if (IFace->getImplementation()) {
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(IFace->getImplementation(), Result,
QualifiedNameLookup, true, Consumer, Visited);
}
} else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
for (ObjCProtocolDecl::protocol_iterator I = Protocol->protocol_begin(),
E = Protocol->protocol_end(); I != E; ++I) {
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer,
Visited);
}
} else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
for (ObjCCategoryDecl::protocol_iterator I = Category->protocol_begin(),
E = Category->protocol_end(); I != E; ++I) {
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer,
Visited);
}
// If there is an implementation, traverse it.
if (Category->getImplementation()) {
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(Category->getImplementation(), Result,
QualifiedNameLookup, true, Consumer, Visited);
}
}
}
static void LookupVisibleDecls(Scope *S, LookupResult &Result,
UnqualUsingDirectiveSet &UDirs,
VisibleDeclConsumer &Consumer,
VisibleDeclsRecord &Visited) {
if (!S)
return;
if (!S->getEntity() ||
(!S->getParent() &&
!Visited.alreadyVisitedContext((DeclContext *)S->getEntity())) ||
((DeclContext *)S->getEntity())->isFunctionOrMethod()) {
// Walk through the declarations in this Scope.
for (Scope::decl_iterator D = S->decl_begin(), DEnd = S->decl_end();
D != DEnd; ++D) {
if (NamedDecl *ND = dyn_cast<NamedDecl>(*D))
if (Result.isAcceptableDecl(ND)) {
Consumer.FoundDecl(ND, Visited.checkHidden(ND), false);
Visited.add(ND);
}
}
}
// FIXME: C++ [temp.local]p8
DeclContext *Entity = 0;
if (S->getEntity()) {
// Look into this scope's declaration context, along with any of its
// parent lookup contexts (e.g., enclosing classes), up to the point
// where we hit the context stored in the next outer scope.
Entity = (DeclContext *)S->getEntity();
DeclContext *OuterCtx = findOuterContext(S).first; // FIXME
for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx);
Ctx = Ctx->getLookupParent()) {
if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
if (Method->isInstanceMethod()) {
// For instance methods, look for ivars in the method's interface.
LookupResult IvarResult(Result.getSema(), Result.getLookupName(),
Result.getNameLoc(), Sema::LookupMemberName);
if (ObjCInterfaceDecl *IFace = Method->getClassInterface())
LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
/*InBaseClass=*/false, Consumer, Visited);
}
// We've already performed all of the name lookup that we need
// to for Objective-C methods; the next context will be the
// outer scope.
break;
}
if (Ctx->isFunctionOrMethod())
continue;
LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
/*InBaseClass=*/false, Consumer, Visited);
}
} else if (!S->getParent()) {
// Look into the translation unit scope. We walk through the translation
// unit's declaration context, because the Scope itself won't have all of
// the declarations if we loaded a precompiled header.
// FIXME: We would like the translation unit's Scope object to point to the
// translation unit, so we don't need this special "if" branch. However,
// doing so would force the normal C++ name-lookup code to look into the
// translation unit decl when the IdentifierInfo chains would suffice.
// Once we fix that problem (which is part of a more general "don't look
// in DeclContexts unless we have to" optimization), we can eliminate this.
Entity = Result.getSema().Context.getTranslationUnitDecl();
LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
/*InBaseClass=*/false, Consumer, Visited);
}
if (Entity) {
// Lookup visible declarations in any namespaces found by using
// directives.
UnqualUsingDirectiveSet::const_iterator UI, UEnd;
llvm::tie(UI, UEnd) = UDirs.getNamespacesFor(Entity);
for (; UI != UEnd; ++UI)
LookupVisibleDecls(const_cast<DeclContext *>(UI->getNominatedNamespace()),
Result, /*QualifiedNameLookup=*/false,
/*InBaseClass=*/false, Consumer, Visited);
}
// Lookup names in the parent scope.
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited);
}
void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind,
VisibleDeclConsumer &Consumer,
bool IncludeGlobalScope) {
// Determine the set of using directives available during
// unqualified name lookup.
Scope *Initial = S;
UnqualUsingDirectiveSet UDirs;
if (getLangOptions().CPlusPlus) {
// Find the first namespace or translation-unit scope.
while (S && !isNamespaceOrTranslationUnitScope(S))
S = S->getParent();
UDirs.visitScopeChain(Initial, S);
}
UDirs.done();
// Look for visible declarations.
LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
VisibleDeclsRecord Visited;
if (!IncludeGlobalScope)
Visited.visitedContext(Context.getTranslationUnitDecl());
ShadowContextRAII Shadow(Visited);
::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited);
}
void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
VisibleDeclConsumer &Consumer,
bool IncludeGlobalScope) {
LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
VisibleDeclsRecord Visited;
if (!IncludeGlobalScope)
Visited.visitedContext(Context.getTranslationUnitDecl());
ShadowContextRAII Shadow(Visited);
::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
/*InBaseClass=*/false, Consumer, Visited);
}
//----------------------------------------------------------------------------
// Typo correction
//----------------------------------------------------------------------------
namespace {
class TypoCorrectionConsumer : public VisibleDeclConsumer {
/// \brief The name written that is a typo in the source.
llvm::StringRef Typo;
/// \brief The results found that have the smallest edit distance
/// found (so far) with the typo name.
llvm::SmallVector<NamedDecl *, 4> BestResults;
/// \brief The keywords that have the smallest edit distance.
llvm::SmallVector<IdentifierInfo *, 4> BestKeywords;
/// \brief The best edit distance found so far.
unsigned BestEditDistance;
public:
explicit TypoCorrectionConsumer(IdentifierInfo *Typo)
: Typo(Typo->getName()) { }
virtual void FoundDecl(NamedDecl *ND, NamedDecl *Hiding, bool InBaseClass);
void addKeywordResult(ASTContext &Context, llvm::StringRef Keyword);
typedef llvm::SmallVector<NamedDecl *, 4>::const_iterator iterator;
iterator begin() const { return BestResults.begin(); }
iterator end() const { return BestResults.end(); }
void clear_decls() { BestResults.clear(); }
bool empty() const { return BestResults.empty() && BestKeywords.empty(); }
typedef llvm::SmallVector<IdentifierInfo *, 4>::const_iterator
keyword_iterator;
keyword_iterator keyword_begin() const { return BestKeywords.begin(); }
keyword_iterator keyword_end() const { return BestKeywords.end(); }
bool keyword_empty() const { return BestKeywords.empty(); }
unsigned keyword_size() const { return BestKeywords.size(); }
unsigned getBestEditDistance() const { return BestEditDistance; }
};
}
void TypoCorrectionConsumer::FoundDecl(NamedDecl *ND, NamedDecl *Hiding,
bool InBaseClass) {
// Don't consider hidden names for typo correction.
if (Hiding)
return;
// Only consider entities with identifiers for names, ignoring
// special names (constructors, overloaded operators, selectors,
// etc.).
IdentifierInfo *Name = ND->getIdentifier();
if (!Name)
return;
// Compute the edit distance between the typo and the name of this
// entity. If this edit distance is not worse than the best edit
// distance we've seen so far, add it to the list of results.
unsigned ED = Typo.edit_distance(Name->getName());
if (!BestResults.empty() || !BestKeywords.empty()) {
if (ED < BestEditDistance) {
// This result is better than any we've seen before; clear out
// the previous results.
BestResults.clear();
BestKeywords.clear();
BestEditDistance = ED;
} else if (ED > BestEditDistance) {
// This result is worse than the best results we've seen so far;
// ignore it.
return;
}
} else
BestEditDistance = ED;
BestResults.push_back(ND);
}
void TypoCorrectionConsumer::addKeywordResult(ASTContext &Context,
llvm::StringRef Keyword) {
// Compute the edit distance between the typo and this keyword.
// If this edit distance is not worse than the best edit
// distance we've seen so far, add it to the list of results.
unsigned ED = Typo.edit_distance(Keyword);
if (!BestResults.empty() || !BestKeywords.empty()) {
if (ED < BestEditDistance) {
BestResults.clear();
BestKeywords.clear();
BestEditDistance = ED;
} else if (ED > BestEditDistance) {
// This result is worse than the best results we've seen so far;
// ignore it.
return;
}
} else
BestEditDistance = ED;
BestKeywords.push_back(&Context.Idents.get(Keyword));
}
/// \brief Try to "correct" a typo in the source code by finding
/// visible declarations whose names are similar to the name that was
/// present in the source code.
///
/// \param Res the \c LookupResult structure that contains the name
/// that was present in the source code along with the name-lookup
/// criteria used to search for the name. On success, this structure
/// will contain the results of name lookup.
///
/// \param S the scope in which name lookup occurs.
///
/// \param SS the nested-name-specifier that precedes the name we're
/// looking for, if present.
///
/// \param MemberContext if non-NULL, the context in which to look for
/// a member access expression.
///
/// \param EnteringContext whether we're entering the context described by
/// the nested-name-specifier SS.
///
/// \param CTC The context in which typo correction occurs, which impacts the
/// set of keywords permitted.
///
/// \param OPT when non-NULL, the search for visible declarations will
/// also walk the protocols in the qualified interfaces of \p OPT.
///
/// \returns the corrected name if the typo was corrected, otherwise returns an
/// empty \c DeclarationName. When a typo was corrected, the result structure
/// may contain the results of name lookup for the correct name or it may be
/// empty.
DeclarationName Sema::CorrectTypo(LookupResult &Res, Scope *S, CXXScopeSpec *SS,
DeclContext *MemberContext,
bool EnteringContext,
CorrectTypoContext CTC,
const ObjCObjectPointerType *OPT) {
if (Diags.hasFatalErrorOccurred() || !getLangOptions().SpellChecking)
return DeclarationName();
// Provide a stop gap for files that are just seriously broken. Trying
// to correct all typos can turn into a HUGE performance penalty, causing
// some files to take minutes to get rejected by the parser.
// FIXME: Is this the right solution?
if (TyposCorrected == 20)
return DeclarationName();
++TyposCorrected;
// We only attempt to correct typos for identifiers.
IdentifierInfo *Typo = Res.getLookupName().getAsIdentifierInfo();
if (!Typo)
return DeclarationName();
// If the scope specifier itself was invalid, don't try to correct
// typos.
if (SS && SS->isInvalid())
return DeclarationName();
// Never try to correct typos during template deduction or
// instantiation.
if (!ActiveTemplateInstantiations.empty())
return DeclarationName();
TypoCorrectionConsumer Consumer(Typo);
// Perform name lookup to find visible, similarly-named entities.
if (MemberContext) {
LookupVisibleDecls(MemberContext, Res.getLookupKind(), Consumer);
// Look in qualified interfaces.
if (OPT) {
for (ObjCObjectPointerType::qual_iterator
I = OPT->qual_begin(), E = OPT->qual_end();
I != E; ++I)
LookupVisibleDecls(*I, Res.getLookupKind(), Consumer);
}
} else if (SS && SS->isSet()) {
DeclContext *DC = computeDeclContext(*SS, EnteringContext);
if (!DC)
return DeclarationName();
LookupVisibleDecls(DC, Res.getLookupKind(), Consumer);
} else {
LookupVisibleDecls(S, Res.getLookupKind(), Consumer);
}
// Add context-dependent keywords.
bool WantTypeSpecifiers = false;
bool WantExpressionKeywords = false;
bool WantCXXNamedCasts = false;
bool WantRemainingKeywords = false;
switch (CTC) {
case CTC_Unknown:
WantTypeSpecifiers = true;
WantExpressionKeywords = true;
WantCXXNamedCasts = true;
WantRemainingKeywords = true;
if (ObjCMethodDecl *Method = getCurMethodDecl())
if (Method->getClassInterface() &&
Method->getClassInterface()->getSuperClass())
Consumer.addKeywordResult(Context, "super");
break;
case CTC_NoKeywords:
break;
case CTC_Type:
WantTypeSpecifiers = true;
break;
case CTC_ObjCMessageReceiver:
Consumer.addKeywordResult(Context, "super");
// Fall through to handle message receivers like expressions.
case CTC_Expression:
if (getLangOptions().CPlusPlus)
WantTypeSpecifiers = true;
WantExpressionKeywords = true;
// Fall through to get C++ named casts.
case CTC_CXXCasts:
WantCXXNamedCasts = true;
break;
case CTC_MemberLookup:
if (getLangOptions().CPlusPlus)
Consumer.addKeywordResult(Context, "template");
break;
}
if (WantTypeSpecifiers) {
// Add type-specifier keywords to the set of results.
const char *CTypeSpecs[] = {
"char", "const", "double", "enum", "float", "int", "long", "short",
"signed", "struct", "union", "unsigned", "void", "volatile", "_Bool",
"_Complex", "_Imaginary",
// storage-specifiers as well
"extern", "inline", "static", "typedef"
};
const unsigned NumCTypeSpecs = sizeof(CTypeSpecs) / sizeof(CTypeSpecs[0]);
for (unsigned I = 0; I != NumCTypeSpecs; ++I)
Consumer.addKeywordResult(Context, CTypeSpecs[I]);
if (getLangOptions().C99)
Consumer.addKeywordResult(Context, "restrict");
if (getLangOptions().Bool || getLangOptions().CPlusPlus)
Consumer.addKeywordResult(Context, "bool");
if (getLangOptions().CPlusPlus) {
Consumer.addKeywordResult(Context, "class");
Consumer.addKeywordResult(Context, "typename");
Consumer.addKeywordResult(Context, "wchar_t");
if (getLangOptions().CPlusPlus0x) {
Consumer.addKeywordResult(Context, "char16_t");
Consumer.addKeywordResult(Context, "char32_t");
Consumer.addKeywordResult(Context, "constexpr");
Consumer.addKeywordResult(Context, "decltype");
Consumer.addKeywordResult(Context, "thread_local");
}
}
if (getLangOptions().GNUMode)
Consumer.addKeywordResult(Context, "typeof");
}
if (WantCXXNamedCasts && getLangOptions().CPlusPlus) {
Consumer.addKeywordResult(Context, "const_cast");
Consumer.addKeywordResult(Context, "dynamic_cast");
Consumer.addKeywordResult(Context, "reinterpret_cast");
Consumer.addKeywordResult(Context, "static_cast");
}
if (WantExpressionKeywords) {
Consumer.addKeywordResult(Context, "sizeof");
if (getLangOptions().Bool || getLangOptions().CPlusPlus) {
Consumer.addKeywordResult(Context, "false");
Consumer.addKeywordResult(Context, "true");
}
if (getLangOptions().CPlusPlus) {
const char *CXXExprs[] = {
"delete", "new", "operator", "throw", "typeid"
};
const unsigned NumCXXExprs = sizeof(CXXExprs) / sizeof(CXXExprs[0]);
for (unsigned I = 0; I != NumCXXExprs; ++I)
Consumer.addKeywordResult(Context, CXXExprs[I]);
if (isa<CXXMethodDecl>(CurContext) &&
cast<CXXMethodDecl>(CurContext)->isInstance())
Consumer.addKeywordResult(Context, "this");
if (getLangOptions().CPlusPlus0x) {
Consumer.addKeywordResult(Context, "alignof");
Consumer.addKeywordResult(Context, "nullptr");
}
}
}
if (WantRemainingKeywords) {
if (getCurFunctionOrMethodDecl() || getCurBlock()) {
// Statements.
const char *CStmts[] = {
"do", "else", "for", "goto", "if", "return", "switch", "while" };
const unsigned NumCStmts = sizeof(CStmts) / sizeof(CStmts[0]);
for (unsigned I = 0; I != NumCStmts; ++I)
Consumer.addKeywordResult(Context, CStmts[I]);
if (getLangOptions().CPlusPlus) {
Consumer.addKeywordResult(Context, "catch");
Consumer.addKeywordResult(Context, "try");
}
if (S && S->getBreakParent())
Consumer.addKeywordResult(Context, "break");
if (S && S->getContinueParent())
Consumer.addKeywordResult(Context, "continue");
if (!getCurFunction()->SwitchStack.empty()) {
Consumer.addKeywordResult(Context, "case");
Consumer.addKeywordResult(Context, "default");
}
} else {
if (getLangOptions().CPlusPlus) {
Consumer.addKeywordResult(Context, "namespace");
Consumer.addKeywordResult(Context, "template");
}
if (S && S->isClassScope()) {
Consumer.addKeywordResult(Context, "explicit");
Consumer.addKeywordResult(Context, "friend");
Consumer.addKeywordResult(Context, "mutable");
Consumer.addKeywordResult(Context, "private");
Consumer.addKeywordResult(Context, "protected");
Consumer.addKeywordResult(Context, "public");
Consumer.addKeywordResult(Context, "virtual");
}
}
if (getLangOptions().CPlusPlus) {
Consumer.addKeywordResult(Context, "using");
if (getLangOptions().CPlusPlus0x)
Consumer.addKeywordResult(Context, "static_assert");
}
}
// If we haven't found anything, we're done.
if (Consumer.empty())
return DeclarationName();
// Only allow a single, closest name in the result set (it's okay to
// have overloads of that name, though).
DeclarationName BestName;
NamedDecl *BestIvarOrPropertyDecl = 0;
bool FoundIvarOrPropertyDecl = false;
// Check all of the declaration results to find the best name so far.
for (TypoCorrectionConsumer::iterator I = Consumer.begin(),
IEnd = Consumer.end();
I != IEnd; ++I) {
if (!BestName)
BestName = (*I)->getDeclName();
else if (BestName != (*I)->getDeclName())
return DeclarationName();
// \brief Keep track of either an Objective-C ivar or a property, but not
// both.
if (isa<ObjCIvarDecl>(*I) || isa<ObjCPropertyDecl>(*I)) {
if (FoundIvarOrPropertyDecl)
BestIvarOrPropertyDecl = 0;
else {
BestIvarOrPropertyDecl = *I;
FoundIvarOrPropertyDecl = true;
}
}
}
// Now check all of the keyword results to find the best name.
switch (Consumer.keyword_size()) {
case 0:
// No keywords matched.
break;
case 1:
// If we already have a name
if (!BestName) {
// We did not have anything previously,
BestName = *Consumer.keyword_begin();
} else if (BestName.getAsIdentifierInfo() == *Consumer.keyword_begin()) {
// We have a declaration with the same name as a context-sensitive
// keyword. The keyword takes precedence.
BestIvarOrPropertyDecl = 0;
FoundIvarOrPropertyDecl = false;
Consumer.clear_decls();
} else if (CTC == CTC_ObjCMessageReceiver &&
(*Consumer.keyword_begin())->isStr("super")) {
// In an Objective-C message send, give the "super" keyword a slight
// edge over entities not in function or method scope.
for (TypoCorrectionConsumer::iterator I = Consumer.begin(),
IEnd = Consumer.end();
I != IEnd; ++I) {
if ((*I)->getDeclName() == BestName) {
if ((*I)->getDeclContext()->isFunctionOrMethod())
return DeclarationName();
}
}
// Everything found was outside a function or method; the 'super'
// keyword takes precedence.
BestIvarOrPropertyDecl = 0;
FoundIvarOrPropertyDecl = false;
Consumer.clear_decls();
BestName = *Consumer.keyword_begin();
} else {
// Name collision; we will not correct typos.
return DeclarationName();
}
break;
default:
// Name collision; we will not correct typos.
return DeclarationName();
}
// BestName is the closest viable name to what the user
// typed. However, to make sure that we don't pick something that's
// way off, make sure that the user typed at least 3 characters for
// each correction.
unsigned ED = Consumer.getBestEditDistance();
if (ED == 0 || !BestName.getAsIdentifierInfo() ||
(BestName.getAsIdentifierInfo()->getName().size() / ED) < 3)
return DeclarationName();
// Perform name lookup again with the name we chose, and declare
// success if we found something that was not ambiguous.
Res.clear();
Res.setLookupName(BestName);
// If we found an ivar or property, add that result; no further
// lookup is required.
if (BestIvarOrPropertyDecl)
Res.addDecl(BestIvarOrPropertyDecl);
// If we're looking into the context of a member, perform qualified
// name lookup on the best name.
else if (!Consumer.keyword_empty()) {
// The best match was a keyword. Return it.
return BestName;
} else if (MemberContext)
LookupQualifiedName(Res, MemberContext);
// Perform lookup as if we had just parsed the best name.
else
LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false,
EnteringContext);
if (Res.isAmbiguous()) {
Res.suppressDiagnostics();
return DeclarationName();
}
if (Res.getResultKind() != LookupResult::NotFound)
return BestName;
return DeclarationName();
}