llvm-project/clang/lib/Parse/ParseExprCXX.cpp

2985 lines
107 KiB
C++

//===--- ParseExprCXX.cpp - C++ Expression Parsing ------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Expression parsing implementation for C++.
//
//===----------------------------------------------------------------------===//
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclTemplate.h"
#include "RAIIObjectsForParser.h"
#include "clang/Basic/PrettyStackTrace.h"
#include "clang/Lex/LiteralSupport.h"
#include "clang/Parse/ParseDiagnostic.h"
#include "clang/Parse/Parser.h"
#include "clang/Sema/DeclSpec.h"
#include "clang/Sema/ParsedTemplate.h"
#include "clang/Sema/Scope.h"
#include "llvm/Support/ErrorHandling.h"
using namespace clang;
static int SelectDigraphErrorMessage(tok::TokenKind Kind) {
switch (Kind) {
// template name
case tok::unknown: return 0;
// casts
case tok::kw_const_cast: return 1;
case tok::kw_dynamic_cast: return 2;
case tok::kw_reinterpret_cast: return 3;
case tok::kw_static_cast: return 4;
default:
llvm_unreachable("Unknown type for digraph error message.");
}
}
// Are the two tokens adjacent in the same source file?
bool Parser::areTokensAdjacent(const Token &First, const Token &Second) {
SourceManager &SM = PP.getSourceManager();
SourceLocation FirstLoc = SM.getSpellingLoc(First.getLocation());
SourceLocation FirstEnd = FirstLoc.getLocWithOffset(First.getLength());
return FirstEnd == SM.getSpellingLoc(Second.getLocation());
}
// Suggest fixit for "<::" after a cast.
static void FixDigraph(Parser &P, Preprocessor &PP, Token &DigraphToken,
Token &ColonToken, tok::TokenKind Kind, bool AtDigraph) {
// Pull '<:' and ':' off token stream.
if (!AtDigraph)
PP.Lex(DigraphToken);
PP.Lex(ColonToken);
SourceRange Range;
Range.setBegin(DigraphToken.getLocation());
Range.setEnd(ColonToken.getLocation());
P.Diag(DigraphToken.getLocation(), diag::err_missing_whitespace_digraph)
<< SelectDigraphErrorMessage(Kind)
<< FixItHint::CreateReplacement(Range, "< ::");
// Update token information to reflect their change in token type.
ColonToken.setKind(tok::coloncolon);
ColonToken.setLocation(ColonToken.getLocation().getLocWithOffset(-1));
ColonToken.setLength(2);
DigraphToken.setKind(tok::less);
DigraphToken.setLength(1);
// Push new tokens back to token stream.
PP.EnterToken(ColonToken);
if (!AtDigraph)
PP.EnterToken(DigraphToken);
}
// Check for '<::' which should be '< ::' instead of '[:' when following
// a template name.
void Parser::CheckForTemplateAndDigraph(Token &Next, ParsedType ObjectType,
bool EnteringContext,
IdentifierInfo &II, CXXScopeSpec &SS) {
if (!Next.is(tok::l_square) || Next.getLength() != 2)
return;
Token SecondToken = GetLookAheadToken(2);
if (!SecondToken.is(tok::colon) || !areTokensAdjacent(Next, SecondToken))
return;
TemplateTy Template;
UnqualifiedId TemplateName;
TemplateName.setIdentifier(&II, Tok.getLocation());
bool MemberOfUnknownSpecialization;
if (!Actions.isTemplateName(getCurScope(), SS, /*hasTemplateKeyword=*/false,
TemplateName, ObjectType, EnteringContext,
Template, MemberOfUnknownSpecialization))
return;
FixDigraph(*this, PP, Next, SecondToken, tok::unknown,
/*AtDigraph*/false);
}
/// \brief Emits an error for a left parentheses after a double colon.
///
/// When a '(' is found after a '::', emit an error. Attempt to fix the token
/// stream by removing the '(', and the matching ')' if found.
void Parser::CheckForLParenAfterColonColon() {
if (!Tok.is(tok::l_paren))
return;
SourceLocation l_parenLoc = ConsumeParen(), r_parenLoc;
Token Tok1 = getCurToken();
if (!Tok1.is(tok::identifier) && !Tok1.is(tok::star))
return;
if (Tok1.is(tok::identifier)) {
Token Tok2 = GetLookAheadToken(1);
if (Tok2.is(tok::r_paren)) {
ConsumeToken();
PP.EnterToken(Tok1);
r_parenLoc = ConsumeParen();
}
} else if (Tok1.is(tok::star)) {
Token Tok2 = GetLookAheadToken(1);
if (Tok2.is(tok::identifier)) {
Token Tok3 = GetLookAheadToken(2);
if (Tok3.is(tok::r_paren)) {
ConsumeToken();
ConsumeToken();
PP.EnterToken(Tok2);
PP.EnterToken(Tok1);
r_parenLoc = ConsumeParen();
}
}
}
Diag(l_parenLoc, diag::err_paren_after_colon_colon)
<< FixItHint::CreateRemoval(l_parenLoc)
<< FixItHint::CreateRemoval(r_parenLoc);
}
/// \brief Parse global scope or nested-name-specifier if present.
///
/// Parses a C++ global scope specifier ('::') or nested-name-specifier (which
/// may be preceded by '::'). Note that this routine will not parse ::new or
/// ::delete; it will just leave them in the token stream.
///
/// '::'[opt] nested-name-specifier
/// '::'
///
/// nested-name-specifier:
/// type-name '::'
/// namespace-name '::'
/// nested-name-specifier identifier '::'
/// nested-name-specifier 'template'[opt] simple-template-id '::'
///
///
/// \param SS the scope specifier that will be set to the parsed
/// nested-name-specifier (or empty)
///
/// \param ObjectType if this nested-name-specifier is being parsed following
/// the "." or "->" of a member access expression, this parameter provides the
/// type of the object whose members are being accessed.
///
/// \param EnteringContext whether we will be entering into the context of
/// the nested-name-specifier after parsing it.
///
/// \param MayBePseudoDestructor When non-NULL, points to a flag that
/// indicates whether this nested-name-specifier may be part of a
/// pseudo-destructor name. In this case, the flag will be set false
/// if we don't actually end up parsing a destructor name. Moreorover,
/// if we do end up determining that we are parsing a destructor name,
/// the last component of the nested-name-specifier is not parsed as
/// part of the scope specifier.
///
/// \param IsTypename If \c true, this nested-name-specifier is known to be
/// part of a type name. This is used to improve error recovery.
///
/// \param LastII When non-NULL, points to an IdentifierInfo* that will be
/// filled in with the leading identifier in the last component of the
/// nested-name-specifier, if any.
///
/// \returns true if there was an error parsing a scope specifier
bool Parser::ParseOptionalCXXScopeSpecifier(CXXScopeSpec &SS,
ParsedType ObjectType,
bool EnteringContext,
bool *MayBePseudoDestructor,
bool IsTypename,
IdentifierInfo **LastII) {
assert(getLangOpts().CPlusPlus &&
"Call sites of this function should be guarded by checking for C++");
if (Tok.is(tok::annot_cxxscope)) {
assert(!LastII && "want last identifier but have already annotated scope");
Actions.RestoreNestedNameSpecifierAnnotation(Tok.getAnnotationValue(),
Tok.getAnnotationRange(),
SS);
ConsumeToken();
return false;
}
if (Tok.is(tok::annot_template_id)) {
// If the current token is an annotated template id, it may already have
// a scope specifier. Restore it.
TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
SS = TemplateId->SS;
}
if (LastII)
*LastII = 0;
bool HasScopeSpecifier = false;
if (Tok.is(tok::coloncolon)) {
// ::new and ::delete aren't nested-name-specifiers.
tok::TokenKind NextKind = NextToken().getKind();
if (NextKind == tok::kw_new || NextKind == tok::kw_delete)
return false;
// '::' - Global scope qualifier.
if (Actions.ActOnCXXGlobalScopeSpecifier(getCurScope(), ConsumeToken(), SS))
return true;
CheckForLParenAfterColonColon();
HasScopeSpecifier = true;
}
bool CheckForDestructor = false;
if (MayBePseudoDestructor && *MayBePseudoDestructor) {
CheckForDestructor = true;
*MayBePseudoDestructor = false;
}
if (Tok.is(tok::kw_decltype) || Tok.is(tok::annot_decltype)) {
DeclSpec DS(AttrFactory);
SourceLocation DeclLoc = Tok.getLocation();
SourceLocation EndLoc = ParseDecltypeSpecifier(DS);
SourceLocation CCLoc;
if (!TryConsumeToken(tok::coloncolon, CCLoc)) {
AnnotateExistingDecltypeSpecifier(DS, DeclLoc, EndLoc);
return false;
}
if (Actions.ActOnCXXNestedNameSpecifierDecltype(SS, DS, CCLoc))
SS.SetInvalid(SourceRange(DeclLoc, CCLoc));
HasScopeSpecifier = true;
}
while (true) {
if (HasScopeSpecifier) {
// C++ [basic.lookup.classref]p5:
// If the qualified-id has the form
//
// ::class-name-or-namespace-name::...
//
// the class-name-or-namespace-name is looked up in global scope as a
// class-name or namespace-name.
//
// To implement this, we clear out the object type as soon as we've
// seen a leading '::' or part of a nested-name-specifier.
ObjectType = ParsedType();
if (Tok.is(tok::code_completion)) {
// Code completion for a nested-name-specifier, where the code
// code completion token follows the '::'.
Actions.CodeCompleteQualifiedId(getCurScope(), SS, EnteringContext);
// Include code completion token into the range of the scope otherwise
// when we try to annotate the scope tokens the dangling code completion
// token will cause assertion in
// Preprocessor::AnnotatePreviousCachedTokens.
SS.setEndLoc(Tok.getLocation());
cutOffParsing();
return true;
}
}
// nested-name-specifier:
// nested-name-specifier 'template'[opt] simple-template-id '::'
// Parse the optional 'template' keyword, then make sure we have
// 'identifier <' after it.
if (Tok.is(tok::kw_template)) {
// If we don't have a scope specifier or an object type, this isn't a
// nested-name-specifier, since they aren't allowed to start with
// 'template'.
if (!HasScopeSpecifier && !ObjectType)
break;
TentativeParsingAction TPA(*this);
SourceLocation TemplateKWLoc = ConsumeToken();
UnqualifiedId TemplateName;
if (Tok.is(tok::identifier)) {
// Consume the identifier.
TemplateName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
ConsumeToken();
} else if (Tok.is(tok::kw_operator)) {
// We don't need to actually parse the unqualified-id in this case,
// because a simple-template-id cannot start with 'operator', but
// go ahead and parse it anyway for consistency with the case where
// we already annotated the template-id.
if (ParseUnqualifiedIdOperator(SS, EnteringContext, ObjectType,
TemplateName)) {
TPA.Commit();
break;
}
if (TemplateName.getKind() != UnqualifiedId::IK_OperatorFunctionId &&
TemplateName.getKind() != UnqualifiedId::IK_LiteralOperatorId) {
Diag(TemplateName.getSourceRange().getBegin(),
diag::err_id_after_template_in_nested_name_spec)
<< TemplateName.getSourceRange();
TPA.Commit();
break;
}
} else {
TPA.Revert();
break;
}
// If the next token is not '<', we have a qualified-id that refers
// to a template name, such as T::template apply, but is not a
// template-id.
if (Tok.isNot(tok::less)) {
TPA.Revert();
break;
}
// Commit to parsing the template-id.
TPA.Commit();
TemplateTy Template;
if (TemplateNameKind TNK
= Actions.ActOnDependentTemplateName(getCurScope(),
SS, TemplateKWLoc, TemplateName,
ObjectType, EnteringContext,
Template)) {
if (AnnotateTemplateIdToken(Template, TNK, SS, TemplateKWLoc,
TemplateName, false))
return true;
} else
return true;
continue;
}
if (Tok.is(tok::annot_template_id) && NextToken().is(tok::coloncolon)) {
// We have
//
// template-id '::'
//
// So we need to check whether the template-id is a simple-template-id of
// the right kind (it should name a type or be dependent), and then
// convert it into a type within the nested-name-specifier.
TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
if (CheckForDestructor && GetLookAheadToken(2).is(tok::tilde)) {
*MayBePseudoDestructor = true;
return false;
}
if (LastII)
*LastII = TemplateId->Name;
// Consume the template-id token.
ConsumeToken();
assert(Tok.is(tok::coloncolon) && "NextToken() not working properly!");
SourceLocation CCLoc = ConsumeToken();
HasScopeSpecifier = true;
ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
TemplateId->NumArgs);
if (Actions.ActOnCXXNestedNameSpecifier(getCurScope(),
SS,
TemplateId->TemplateKWLoc,
TemplateId->Template,
TemplateId->TemplateNameLoc,
TemplateId->LAngleLoc,
TemplateArgsPtr,
TemplateId->RAngleLoc,
CCLoc,
EnteringContext)) {
SourceLocation StartLoc
= SS.getBeginLoc().isValid()? SS.getBeginLoc()
: TemplateId->TemplateNameLoc;
SS.SetInvalid(SourceRange(StartLoc, CCLoc));
}
continue;
}
// The rest of the nested-name-specifier possibilities start with
// tok::identifier.
if (Tok.isNot(tok::identifier))
break;
IdentifierInfo &II = *Tok.getIdentifierInfo();
// nested-name-specifier:
// type-name '::'
// namespace-name '::'
// nested-name-specifier identifier '::'
Token Next = NextToken();
// If we get foo:bar, this is almost certainly a typo for foo::bar. Recover
// and emit a fixit hint for it.
if (Next.is(tok::colon) && !ColonIsSacred) {
if (Actions.IsInvalidUnlessNestedName(getCurScope(), SS, II,
Tok.getLocation(),
Next.getLocation(), ObjectType,
EnteringContext) &&
// If the token after the colon isn't an identifier, it's still an
// error, but they probably meant something else strange so don't
// recover like this.
PP.LookAhead(1).is(tok::identifier)) {
Diag(Next, diag::err_unexected_colon_in_nested_name_spec)
<< FixItHint::CreateReplacement(Next.getLocation(), "::");
// Recover as if the user wrote '::'.
Next.setKind(tok::coloncolon);
}
}
if (Next.is(tok::coloncolon)) {
if (CheckForDestructor && GetLookAheadToken(2).is(tok::tilde) &&
!Actions.isNonTypeNestedNameSpecifier(getCurScope(), SS, Tok.getLocation(),
II, ObjectType)) {
*MayBePseudoDestructor = true;
return false;
}
if (LastII)
*LastII = &II;
// We have an identifier followed by a '::'. Lookup this name
// as the name in a nested-name-specifier.
SourceLocation IdLoc = ConsumeToken();
assert((Tok.is(tok::coloncolon) || Tok.is(tok::colon)) &&
"NextToken() not working properly!");
SourceLocation CCLoc = ConsumeToken();
CheckForLParenAfterColonColon();
HasScopeSpecifier = true;
if (Actions.ActOnCXXNestedNameSpecifier(getCurScope(), II, IdLoc, CCLoc,
ObjectType, EnteringContext, SS))
SS.SetInvalid(SourceRange(IdLoc, CCLoc));
continue;
}
CheckForTemplateAndDigraph(Next, ObjectType, EnteringContext, II, SS);
// nested-name-specifier:
// type-name '<'
if (Next.is(tok::less)) {
TemplateTy Template;
UnqualifiedId TemplateName;
TemplateName.setIdentifier(&II, Tok.getLocation());
bool MemberOfUnknownSpecialization;
if (TemplateNameKind TNK = Actions.isTemplateName(getCurScope(), SS,
/*hasTemplateKeyword=*/false,
TemplateName,
ObjectType,
EnteringContext,
Template,
MemberOfUnknownSpecialization)) {
// We have found a template name, so annotate this token
// with a template-id annotation. We do not permit the
// template-id to be translated into a type annotation,
// because some clients (e.g., the parsing of class template
// specializations) still want to see the original template-id
// token.
ConsumeToken();
if (AnnotateTemplateIdToken(Template, TNK, SS, SourceLocation(),
TemplateName, false))
return true;
continue;
}
if (MemberOfUnknownSpecialization && (ObjectType || SS.isSet()) &&
(IsTypename || IsTemplateArgumentList(1))) {
// We have something like t::getAs<T>, where getAs is a
// member of an unknown specialization. However, this will only
// parse correctly as a template, so suggest the keyword 'template'
// before 'getAs' and treat this as a dependent template name.
unsigned DiagID = diag::err_missing_dependent_template_keyword;
if (getLangOpts().MicrosoftExt)
DiagID = diag::warn_missing_dependent_template_keyword;
Diag(Tok.getLocation(), DiagID)
<< II.getName()
<< FixItHint::CreateInsertion(Tok.getLocation(), "template ");
if (TemplateNameKind TNK
= Actions.ActOnDependentTemplateName(getCurScope(),
SS, SourceLocation(),
TemplateName, ObjectType,
EnteringContext, Template)) {
// Consume the identifier.
ConsumeToken();
if (AnnotateTemplateIdToken(Template, TNK, SS, SourceLocation(),
TemplateName, false))
return true;
}
else
return true;
continue;
}
}
// We don't have any tokens that form the beginning of a
// nested-name-specifier, so we're done.
break;
}
// Even if we didn't see any pieces of a nested-name-specifier, we
// still check whether there is a tilde in this position, which
// indicates a potential pseudo-destructor.
if (CheckForDestructor && Tok.is(tok::tilde))
*MayBePseudoDestructor = true;
return false;
}
/// ParseCXXIdExpression - Handle id-expression.
///
/// id-expression:
/// unqualified-id
/// qualified-id
///
/// qualified-id:
/// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id
/// '::' identifier
/// '::' operator-function-id
/// '::' template-id
///
/// NOTE: The standard specifies that, for qualified-id, the parser does not
/// expect:
///
/// '::' conversion-function-id
/// '::' '~' class-name
///
/// This may cause a slight inconsistency on diagnostics:
///
/// class C {};
/// namespace A {}
/// void f() {
/// :: A :: ~ C(); // Some Sema error about using destructor with a
/// // namespace.
/// :: ~ C(); // Some Parser error like 'unexpected ~'.
/// }
///
/// We simplify the parser a bit and make it work like:
///
/// qualified-id:
/// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id
/// '::' unqualified-id
///
/// That way Sema can handle and report similar errors for namespaces and the
/// global scope.
///
/// The isAddressOfOperand parameter indicates that this id-expression is a
/// direct operand of the address-of operator. This is, besides member contexts,
/// the only place where a qualified-id naming a non-static class member may
/// appear.
///
ExprResult Parser::ParseCXXIdExpression(bool isAddressOfOperand) {
// qualified-id:
// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id
// '::' unqualified-id
//
CXXScopeSpec SS;
ParseOptionalCXXScopeSpecifier(SS, ParsedType(), /*EnteringContext=*/false);
SourceLocation TemplateKWLoc;
UnqualifiedId Name;
if (ParseUnqualifiedId(SS,
/*EnteringContext=*/false,
/*AllowDestructorName=*/false,
/*AllowConstructorName=*/false,
/*ObjectType=*/ ParsedType(),
TemplateKWLoc,
Name))
return ExprError();
// This is only the direct operand of an & operator if it is not
// followed by a postfix-expression suffix.
if (isAddressOfOperand && isPostfixExpressionSuffixStart())
isAddressOfOperand = false;
return Actions.ActOnIdExpression(getCurScope(), SS, TemplateKWLoc, Name,
Tok.is(tok::l_paren), isAddressOfOperand);
}
/// ParseLambdaExpression - Parse a C++11 lambda expression.
///
/// lambda-expression:
/// lambda-introducer lambda-declarator[opt] compound-statement
///
/// lambda-introducer:
/// '[' lambda-capture[opt] ']'
///
/// lambda-capture:
/// capture-default
/// capture-list
/// capture-default ',' capture-list
///
/// capture-default:
/// '&'
/// '='
///
/// capture-list:
/// capture
/// capture-list ',' capture
///
/// capture:
/// simple-capture
/// init-capture [C++1y]
///
/// simple-capture:
/// identifier
/// '&' identifier
/// 'this'
///
/// init-capture: [C++1y]
/// identifier initializer
/// '&' identifier initializer
///
/// lambda-declarator:
/// '(' parameter-declaration-clause ')' attribute-specifier[opt]
/// 'mutable'[opt] exception-specification[opt]
/// trailing-return-type[opt]
///
ExprResult Parser::ParseLambdaExpression() {
// Parse lambda-introducer.
LambdaIntroducer Intro;
Optional<unsigned> DiagID = ParseLambdaIntroducer(Intro);
if (DiagID) {
Diag(Tok, DiagID.getValue());
SkipUntil(tok::r_square, StopAtSemi);
SkipUntil(tok::l_brace, StopAtSemi);
SkipUntil(tok::r_brace, StopAtSemi);
return ExprError();
}
return ParseLambdaExpressionAfterIntroducer(Intro);
}
/// TryParseLambdaExpression - Use lookahead and potentially tentative
/// parsing to determine if we are looking at a C++0x lambda expression, and parse
/// it if we are.
///
/// If we are not looking at a lambda expression, returns ExprError().
ExprResult Parser::TryParseLambdaExpression() {
assert(getLangOpts().CPlusPlus11
&& Tok.is(tok::l_square)
&& "Not at the start of a possible lambda expression.");
const Token Next = NextToken(), After = GetLookAheadToken(2);
// If lookahead indicates this is a lambda...
if (Next.is(tok::r_square) || // []
Next.is(tok::equal) || // [=
(Next.is(tok::amp) && // [&] or [&,
(After.is(tok::r_square) ||
After.is(tok::comma))) ||
(Next.is(tok::identifier) && // [identifier]
After.is(tok::r_square))) {
return ParseLambdaExpression();
}
// If lookahead indicates an ObjC message send...
// [identifier identifier
if (Next.is(tok::identifier) && After.is(tok::identifier)) {
return ExprEmpty();
}
// Here, we're stuck: lambda introducers and Objective-C message sends are
// unambiguous, but it requires arbitrary lookhead. [a,b,c,d,e,f,g] is a
// lambda, and [a,b,c,d,e,f,g h] is a Objective-C message send. Instead of
// writing two routines to parse a lambda introducer, just try to parse
// a lambda introducer first, and fall back if that fails.
// (TryParseLambdaIntroducer never produces any diagnostic output.)
LambdaIntroducer Intro;
if (TryParseLambdaIntroducer(Intro))
return ExprEmpty();
return ParseLambdaExpressionAfterIntroducer(Intro);
}
/// \brief Parse a lambda introducer.
/// \param Intro A LambdaIntroducer filled in with information about the
/// contents of the lambda-introducer.
/// \param SkippedInits If non-null, we are disambiguating between an Obj-C
/// message send and a lambda expression. In this mode, we will
/// sometimes skip the initializers for init-captures and not fully
/// populate \p Intro. This flag will be set to \c true if we do so.
/// \return A DiagnosticID if it hit something unexpected. The location for
/// for the diagnostic is that of the current token.
Optional<unsigned> Parser::ParseLambdaIntroducer(LambdaIntroducer &Intro,
bool *SkippedInits) {
typedef Optional<unsigned> DiagResult;
assert(Tok.is(tok::l_square) && "Lambda expressions begin with '['.");
BalancedDelimiterTracker T(*this, tok::l_square);
T.consumeOpen();
Intro.Range.setBegin(T.getOpenLocation());
bool first = true;
// Parse capture-default.
if (Tok.is(tok::amp) &&
(NextToken().is(tok::comma) || NextToken().is(tok::r_square))) {
Intro.Default = LCD_ByRef;
Intro.DefaultLoc = ConsumeToken();
first = false;
} else if (Tok.is(tok::equal)) {
Intro.Default = LCD_ByCopy;
Intro.DefaultLoc = ConsumeToken();
first = false;
}
while (Tok.isNot(tok::r_square)) {
if (!first) {
if (Tok.isNot(tok::comma)) {
// Provide a completion for a lambda introducer here. Except
// in Objective-C, where this is Almost Surely meant to be a message
// send. In that case, fail here and let the ObjC message
// expression parser perform the completion.
if (Tok.is(tok::code_completion) &&
!(getLangOpts().ObjC1 && Intro.Default == LCD_None &&
!Intro.Captures.empty())) {
Actions.CodeCompleteLambdaIntroducer(getCurScope(), Intro,
/*AfterAmpersand=*/false);
ConsumeCodeCompletionToken();
break;
}
return DiagResult(diag::err_expected_comma_or_rsquare);
}
ConsumeToken();
}
if (Tok.is(tok::code_completion)) {
// If we're in Objective-C++ and we have a bare '[', then this is more
// likely to be a message receiver.
if (getLangOpts().ObjC1 && first)
Actions.CodeCompleteObjCMessageReceiver(getCurScope());
else
Actions.CodeCompleteLambdaIntroducer(getCurScope(), Intro,
/*AfterAmpersand=*/false);
ConsumeCodeCompletionToken();
break;
}
first = false;
// Parse capture.
LambdaCaptureKind Kind = LCK_ByCopy;
SourceLocation Loc;
IdentifierInfo* Id = 0;
SourceLocation EllipsisLoc;
ExprResult Init;
if (Tok.is(tok::kw_this)) {
Kind = LCK_This;
Loc = ConsumeToken();
} else {
if (Tok.is(tok::amp)) {
Kind = LCK_ByRef;
ConsumeToken();
if (Tok.is(tok::code_completion)) {
Actions.CodeCompleteLambdaIntroducer(getCurScope(), Intro,
/*AfterAmpersand=*/true);
ConsumeCodeCompletionToken();
break;
}
}
if (Tok.is(tok::identifier)) {
Id = Tok.getIdentifierInfo();
Loc = ConsumeToken();
} else if (Tok.is(tok::kw_this)) {
// FIXME: If we want to suggest a fixit here, will need to return more
// than just DiagnosticID. Perhaps full DiagnosticBuilder that can be
// Clear()ed to prevent emission in case of tentative parsing?
return DiagResult(diag::err_this_captured_by_reference);
} else {
return DiagResult(diag::err_expected_capture);
}
if (Tok.is(tok::l_paren)) {
BalancedDelimiterTracker Parens(*this, tok::l_paren);
Parens.consumeOpen();
ExprVector Exprs;
CommaLocsTy Commas;
if (SkippedInits) {
Parens.skipToEnd();
*SkippedInits = true;
} else if (ParseExpressionList(Exprs, Commas)) {
Parens.skipToEnd();
Init = ExprError();
} else {
Parens.consumeClose();
Init = Actions.ActOnParenListExpr(Parens.getOpenLocation(),
Parens.getCloseLocation(),
Exprs);
}
} else if (Tok.is(tok::l_brace) || Tok.is(tok::equal)) {
// Each lambda init-capture forms its own full expression, which clears
// Actions.MaybeODRUseExprs. So create an expression evaluation context
// to save the necessary state, and restore it later.
EnterExpressionEvaluationContext EC(Actions,
Sema::PotentiallyEvaluated);
TryConsumeToken(tok::equal);
if (!SkippedInits)
Init = ParseInitializer();
else if (Tok.is(tok::l_brace)) {
BalancedDelimiterTracker Braces(*this, tok::l_brace);
Braces.consumeOpen();
Braces.skipToEnd();
*SkippedInits = true;
} else {
// We're disambiguating this:
//
// [..., x = expr
//
// We need to find the end of the following expression in order to
// determine whether this is an Obj-C message send's receiver, or a
// lambda init-capture.
//
// Parse the expression to find where it ends, and annotate it back
// onto the tokens. We would have parsed this expression the same way
// in either case: both the RHS of an init-capture and the RHS of an
// assignment expression are parsed as an initializer-clause, and in
// neither case can anything be added to the scope between the '[' and
// here.
//
// FIXME: This is horrible. Adding a mechanism to skip an expression
// would be much cleaner.
// FIXME: If there is a ',' before the next ']' or ':', we can skip to
// that instead. (And if we see a ':' with no matching '?', we can
// classify this as an Obj-C message send.)
SourceLocation StartLoc = Tok.getLocation();
InMessageExpressionRAIIObject MaybeInMessageExpression(*this, true);
Init = ParseInitializer();
if (Tok.getLocation() != StartLoc) {
// Back out the lexing of the token after the initializer.
PP.RevertCachedTokens(1);
// Replace the consumed tokens with an appropriate annotation.
Tok.setLocation(StartLoc);
Tok.setKind(tok::annot_primary_expr);
setExprAnnotation(Tok, Init);
Tok.setAnnotationEndLoc(PP.getLastCachedTokenLocation());
PP.AnnotateCachedTokens(Tok);
// Consume the annotated initializer.
ConsumeToken();
}
}
} else
TryConsumeToken(tok::ellipsis, EllipsisLoc);
}
// If this is an init capture, process the initialization expression
// right away. For lambda init-captures such as the following:
// const int x = 10;
// auto L = [i = x+1](int a) {
// return [j = x+2,
// &k = x](char b) { };
// };
// keep in mind that each lambda init-capture has to have:
// - its initialization expression executed in the context
// of the enclosing/parent decl-context.
// - but the variable itself has to be 'injected' into the
// decl-context of its lambda's call-operator (which has
// not yet been created).
// Each init-expression is a full-expression that has to get
// Sema-analyzed (for capturing etc.) before its lambda's
// call-operator's decl-context, scope & scopeinfo are pushed on their
// respective stacks. Thus if any variable is odr-used in the init-capture
// it will correctly get captured in the enclosing lambda, if one exists.
// The init-variables above are created later once the lambdascope and
// call-operators decl-context is pushed onto its respective stack.
// Since the lambda init-capture's initializer expression occurs in the
// context of the enclosing function or lambda, therefore we can not wait
// till a lambda scope has been pushed on before deciding whether the
// variable needs to be captured. We also need to process all
// lvalue-to-rvalue conversions and discarded-value conversions,
// so that we can avoid capturing certain constant variables.
// For e.g.,
// void test() {
// const int x = 10;
// auto L = [&z = x](char a) { <-- don't capture by the current lambda
// return [y = x](int i) { <-- don't capture by enclosing lambda
// return y;
// }
// };
// If x was not const, the second use would require 'L' to capture, and
// that would be an error.
ParsedType InitCaptureParsedType;
if (Init.isUsable()) {
// Get the pointer and store it in an lvalue, so we can use it as an
// out argument.
Expr *InitExpr = Init.get();
// This performs any lvalue-to-rvalue conversions if necessary, which
// can affect what gets captured in the containing decl-context.
QualType InitCaptureType = Actions.performLambdaInitCaptureInitialization(
Loc, Kind == LCK_ByRef, Id, InitExpr);
Init = InitExpr;
InitCaptureParsedType.set(InitCaptureType);
}
Intro.addCapture(Kind, Loc, Id, EllipsisLoc, Init, InitCaptureParsedType);
}
T.consumeClose();
Intro.Range.setEnd(T.getCloseLocation());
return DiagResult();
}
/// TryParseLambdaIntroducer - Tentatively parse a lambda introducer.
///
/// Returns true if it hit something unexpected.
bool Parser::TryParseLambdaIntroducer(LambdaIntroducer &Intro) {
TentativeParsingAction PA(*this);
bool SkippedInits = false;
Optional<unsigned> DiagID(ParseLambdaIntroducer(Intro, &SkippedInits));
if (DiagID) {
PA.Revert();
return true;
}
if (SkippedInits) {
// Parse it again, but this time parse the init-captures too.
PA.Revert();
Intro = LambdaIntroducer();
DiagID = ParseLambdaIntroducer(Intro);
assert(!DiagID && "parsing lambda-introducer failed on reparse");
return false;
}
PA.Commit();
return false;
}
/// ParseLambdaExpressionAfterIntroducer - Parse the rest of a lambda
/// expression.
ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
LambdaIntroducer &Intro) {
SourceLocation LambdaBeginLoc = Intro.Range.getBegin();
Diag(LambdaBeginLoc, diag::warn_cxx98_compat_lambda);
PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), LambdaBeginLoc,
"lambda expression parsing");
// FIXME: Call into Actions to add any init-capture declarations to the
// scope while parsing the lambda-declarator and compound-statement.
// Parse lambda-declarator[opt].
DeclSpec DS(AttrFactory);
Declarator D(DS, Declarator::LambdaExprContext);
TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
Actions.PushLambdaScope();
if (Tok.is(tok::l_paren)) {
ParseScope PrototypeScope(this,
Scope::FunctionPrototypeScope |
Scope::FunctionDeclarationScope |
Scope::DeclScope);
SourceLocation DeclEndLoc;
BalancedDelimiterTracker T(*this, tok::l_paren);
T.consumeOpen();
SourceLocation LParenLoc = T.getOpenLocation();
// Parse parameter-declaration-clause.
ParsedAttributes Attr(AttrFactory);
SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
SourceLocation EllipsisLoc;
if (Tok.isNot(tok::r_paren)) {
Actions.RecordParsingTemplateParameterDepth(TemplateParameterDepth);
ParseParameterDeclarationClause(D, Attr, ParamInfo, EllipsisLoc);
// For a generic lambda, each 'auto' within the parameter declaration
// clause creates a template type parameter, so increment the depth.
if (Actions.getCurGenericLambda())
++CurTemplateDepthTracker;
}
T.consumeClose();
SourceLocation RParenLoc = T.getCloseLocation();
DeclEndLoc = RParenLoc;
// Parse 'mutable'[opt].
SourceLocation MutableLoc;
if (TryConsumeToken(tok::kw_mutable, MutableLoc))
DeclEndLoc = MutableLoc;
// Parse exception-specification[opt].
ExceptionSpecificationType ESpecType = EST_None;
SourceRange ESpecRange;
SmallVector<ParsedType, 2> DynamicExceptions;
SmallVector<SourceRange, 2> DynamicExceptionRanges;
ExprResult NoexceptExpr;
ESpecType = tryParseExceptionSpecification(ESpecRange,
DynamicExceptions,
DynamicExceptionRanges,
NoexceptExpr);
if (ESpecType != EST_None)
DeclEndLoc = ESpecRange.getEnd();
// Parse attribute-specifier[opt].
MaybeParseCXX11Attributes(Attr, &DeclEndLoc);
SourceLocation FunLocalRangeEnd = DeclEndLoc;
// Parse trailing-return-type[opt].
TypeResult TrailingReturnType;
if (Tok.is(tok::arrow)) {
FunLocalRangeEnd = Tok.getLocation();
SourceRange Range;
TrailingReturnType = ParseTrailingReturnType(Range);
if (Range.getEnd().isValid())
DeclEndLoc = Range.getEnd();
}
PrototypeScope.Exit();
SourceLocation NoLoc;
D.AddTypeInfo(DeclaratorChunk::getFunction(/*hasProto=*/true,
/*isAmbiguous=*/false,
LParenLoc,
ParamInfo.data(), ParamInfo.size(),
EllipsisLoc, RParenLoc,
DS.getTypeQualifiers(),
/*RefQualifierIsLValueRef=*/true,
/*RefQualifierLoc=*/NoLoc,
/*ConstQualifierLoc=*/NoLoc,
/*VolatileQualifierLoc=*/NoLoc,
MutableLoc,
ESpecType, ESpecRange.getBegin(),
DynamicExceptions.data(),
DynamicExceptionRanges.data(),
DynamicExceptions.size(),
NoexceptExpr.isUsable() ?
NoexceptExpr.get() : 0,
LParenLoc, FunLocalRangeEnd, D,
TrailingReturnType),
Attr, DeclEndLoc);
} else if (Tok.is(tok::kw_mutable) || Tok.is(tok::arrow)) {
// It's common to forget that one needs '()' before 'mutable' or the
// result type. Deal with this.
Diag(Tok, diag::err_lambda_missing_parens)
<< Tok.is(tok::arrow)
<< FixItHint::CreateInsertion(Tok.getLocation(), "() ");
SourceLocation DeclLoc = Tok.getLocation();
SourceLocation DeclEndLoc = DeclLoc;
// Parse 'mutable', if it's there.
SourceLocation MutableLoc;
if (Tok.is(tok::kw_mutable)) {
MutableLoc = ConsumeToken();
DeclEndLoc = MutableLoc;
}
// Parse the return type, if there is one.
TypeResult TrailingReturnType;
if (Tok.is(tok::arrow)) {
SourceRange Range;
TrailingReturnType = ParseTrailingReturnType(Range);
if (Range.getEnd().isValid())
DeclEndLoc = Range.getEnd();
}
ParsedAttributes Attr(AttrFactory);
SourceLocation NoLoc;
D.AddTypeInfo(DeclaratorChunk::getFunction(/*hasProto=*/true,
/*isAmbiguous=*/false,
/*LParenLoc=*/NoLoc,
/*Params=*/0,
/*NumParams=*/0,
/*EllipsisLoc=*/NoLoc,
/*RParenLoc=*/NoLoc,
/*TypeQuals=*/0,
/*RefQualifierIsLValueRef=*/true,
/*RefQualifierLoc=*/NoLoc,
/*ConstQualifierLoc=*/NoLoc,
/*VolatileQualifierLoc=*/NoLoc,
MutableLoc,
EST_None,
/*ESpecLoc=*/NoLoc,
/*Exceptions=*/0,
/*ExceptionRanges=*/0,
/*NumExceptions=*/0,
/*NoexceptExpr=*/0,
DeclLoc, DeclEndLoc, D,
TrailingReturnType),
Attr, DeclEndLoc);
}
// FIXME: Rename BlockScope -> ClosureScope if we decide to continue using
// it.
unsigned ScopeFlags = Scope::BlockScope | Scope::FnScope | Scope::DeclScope;
ParseScope BodyScope(this, ScopeFlags);
Actions.ActOnStartOfLambdaDefinition(Intro, D, getCurScope());
// Parse compound-statement.
if (!Tok.is(tok::l_brace)) {
Diag(Tok, diag::err_expected_lambda_body);
Actions.ActOnLambdaError(LambdaBeginLoc, getCurScope());
return ExprError();
}
StmtResult Stmt(ParseCompoundStatementBody());
BodyScope.Exit();
if (!Stmt.isInvalid())
return Actions.ActOnLambdaExpr(LambdaBeginLoc, Stmt.take(), getCurScope());
Actions.ActOnLambdaError(LambdaBeginLoc, getCurScope());
return ExprError();
}
/// ParseCXXCasts - This handles the various ways to cast expressions to another
/// type.
///
/// postfix-expression: [C++ 5.2p1]
/// 'dynamic_cast' '<' type-name '>' '(' expression ')'
/// 'static_cast' '<' type-name '>' '(' expression ')'
/// 'reinterpret_cast' '<' type-name '>' '(' expression ')'
/// 'const_cast' '<' type-name '>' '(' expression ')'
///
ExprResult Parser::ParseCXXCasts() {
tok::TokenKind Kind = Tok.getKind();
const char *CastName = 0; // For error messages
switch (Kind) {
default: llvm_unreachable("Unknown C++ cast!");
case tok::kw_const_cast: CastName = "const_cast"; break;
case tok::kw_dynamic_cast: CastName = "dynamic_cast"; break;
case tok::kw_reinterpret_cast: CastName = "reinterpret_cast"; break;
case tok::kw_static_cast: CastName = "static_cast"; break;
}
SourceLocation OpLoc = ConsumeToken();
SourceLocation LAngleBracketLoc = Tok.getLocation();
// Check for "<::" which is parsed as "[:". If found, fix token stream,
// diagnose error, suggest fix, and recover parsing.
if (Tok.is(tok::l_square) && Tok.getLength() == 2) {
Token Next = NextToken();
if (Next.is(tok::colon) && areTokensAdjacent(Tok, Next))
FixDigraph(*this, PP, Tok, Next, Kind, /*AtDigraph*/true);
}
if (ExpectAndConsume(tok::less, diag::err_expected_less_after, CastName))
return ExprError();
// Parse the common declaration-specifiers piece.
DeclSpec DS(AttrFactory);
ParseSpecifierQualifierList(DS);
// Parse the abstract-declarator, if present.
Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
ParseDeclarator(DeclaratorInfo);
SourceLocation RAngleBracketLoc = Tok.getLocation();
if (ExpectAndConsume(tok::greater))
return ExprError(Diag(LAngleBracketLoc, diag::note_matching) << tok::less);
SourceLocation LParenLoc, RParenLoc;
BalancedDelimiterTracker T(*this, tok::l_paren);
if (T.expectAndConsume(diag::err_expected_lparen_after, CastName))
return ExprError();
ExprResult Result = ParseExpression();
// Match the ')'.
T.consumeClose();
if (!Result.isInvalid() && !DeclaratorInfo.isInvalidType())
Result = Actions.ActOnCXXNamedCast(OpLoc, Kind,
LAngleBracketLoc, DeclaratorInfo,
RAngleBracketLoc,
T.getOpenLocation(), Result.take(),
T.getCloseLocation());
return Result;
}
/// ParseCXXTypeid - This handles the C++ typeid expression.
///
/// postfix-expression: [C++ 5.2p1]
/// 'typeid' '(' expression ')'
/// 'typeid' '(' type-id ')'
///
ExprResult Parser::ParseCXXTypeid() {
assert(Tok.is(tok::kw_typeid) && "Not 'typeid'!");
SourceLocation OpLoc = ConsumeToken();
SourceLocation LParenLoc, RParenLoc;
BalancedDelimiterTracker T(*this, tok::l_paren);
// typeid expressions are always parenthesized.
if (T.expectAndConsume(diag::err_expected_lparen_after, "typeid"))
return ExprError();
LParenLoc = T.getOpenLocation();
ExprResult Result;
// C++0x [expr.typeid]p3:
// When typeid is applied to an expression other than an lvalue of a
// polymorphic class type [...] The expression is an unevaluated
// operand (Clause 5).
//
// Note that we can't tell whether the expression is an lvalue of a
// polymorphic class type until after we've parsed the expression; we
// speculatively assume the subexpression is unevaluated, and fix it up
// later.
//
// We enter the unevaluated context before trying to determine whether we
// have a type-id, because the tentative parse logic will try to resolve
// names, and must treat them as unevaluated.
EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated,
Sema::ReuseLambdaContextDecl);
if (isTypeIdInParens()) {
TypeResult Ty = ParseTypeName();
// Match the ')'.
T.consumeClose();
RParenLoc = T.getCloseLocation();
if (Ty.isInvalid() || RParenLoc.isInvalid())
return ExprError();
Result = Actions.ActOnCXXTypeid(OpLoc, LParenLoc, /*isType=*/true,
Ty.get().getAsOpaquePtr(), RParenLoc);
} else {
Result = ParseExpression();
// Match the ')'.
if (Result.isInvalid())
SkipUntil(tok::r_paren, StopAtSemi);
else {
T.consumeClose();
RParenLoc = T.getCloseLocation();
if (RParenLoc.isInvalid())
return ExprError();
Result = Actions.ActOnCXXTypeid(OpLoc, LParenLoc, /*isType=*/false,
Result.release(), RParenLoc);
}
}
return Result;
}
/// ParseCXXUuidof - This handles the Microsoft C++ __uuidof expression.
///
/// '__uuidof' '(' expression ')'
/// '__uuidof' '(' type-id ')'
///
ExprResult Parser::ParseCXXUuidof() {
assert(Tok.is(tok::kw___uuidof) && "Not '__uuidof'!");
SourceLocation OpLoc = ConsumeToken();
BalancedDelimiterTracker T(*this, tok::l_paren);
// __uuidof expressions are always parenthesized.
if (T.expectAndConsume(diag::err_expected_lparen_after, "__uuidof"))
return ExprError();
ExprResult Result;
if (isTypeIdInParens()) {
TypeResult Ty = ParseTypeName();
// Match the ')'.
T.consumeClose();
if (Ty.isInvalid())
return ExprError();
Result = Actions.ActOnCXXUuidof(OpLoc, T.getOpenLocation(), /*isType=*/true,
Ty.get().getAsOpaquePtr(),
T.getCloseLocation());
} else {
EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated);
Result = ParseExpression();
// Match the ')'.
if (Result.isInvalid())
SkipUntil(tok::r_paren, StopAtSemi);
else {
T.consumeClose();
Result = Actions.ActOnCXXUuidof(OpLoc, T.getOpenLocation(),
/*isType=*/false,
Result.release(), T.getCloseLocation());
}
}
return Result;
}
/// \brief Parse a C++ pseudo-destructor expression after the base,
/// . or -> operator, and nested-name-specifier have already been
/// parsed.
///
/// postfix-expression: [C++ 5.2]
/// postfix-expression . pseudo-destructor-name
/// postfix-expression -> pseudo-destructor-name
///
/// pseudo-destructor-name:
/// ::[opt] nested-name-specifier[opt] type-name :: ~type-name
/// ::[opt] nested-name-specifier template simple-template-id ::
/// ~type-name
/// ::[opt] nested-name-specifier[opt] ~type-name
///
ExprResult
Parser::ParseCXXPseudoDestructor(ExprArg Base, SourceLocation OpLoc,
tok::TokenKind OpKind,
CXXScopeSpec &SS,
ParsedType ObjectType) {
// We're parsing either a pseudo-destructor-name or a dependent
// member access that has the same form as a
// pseudo-destructor-name. We parse both in the same way and let
// the action model sort them out.
//
// Note that the ::[opt] nested-name-specifier[opt] has already
// been parsed, and if there was a simple-template-id, it has
// been coalesced into a template-id annotation token.
UnqualifiedId FirstTypeName;
SourceLocation CCLoc;
if (Tok.is(tok::identifier)) {
FirstTypeName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
ConsumeToken();
assert(Tok.is(tok::coloncolon) &&"ParseOptionalCXXScopeSpecifier fail");
CCLoc = ConsumeToken();
} else if (Tok.is(tok::annot_template_id)) {
// FIXME: retrieve TemplateKWLoc from template-id annotation and
// store it in the pseudo-dtor node (to be used when instantiating it).
FirstTypeName.setTemplateId(
(TemplateIdAnnotation *)Tok.getAnnotationValue());
ConsumeToken();
assert(Tok.is(tok::coloncolon) &&"ParseOptionalCXXScopeSpecifier fail");
CCLoc = ConsumeToken();
} else {
FirstTypeName.setIdentifier(0, SourceLocation());
}
// Parse the tilde.
assert(Tok.is(tok::tilde) && "ParseOptionalCXXScopeSpecifier fail");
SourceLocation TildeLoc = ConsumeToken();
if (Tok.is(tok::kw_decltype) && !FirstTypeName.isValid() && SS.isEmpty()) {
DeclSpec DS(AttrFactory);
ParseDecltypeSpecifier(DS);
if (DS.getTypeSpecType() == TST_error)
return ExprError();
return Actions.ActOnPseudoDestructorExpr(getCurScope(), Base, OpLoc,
OpKind, TildeLoc, DS,
Tok.is(tok::l_paren));
}
if (!Tok.is(tok::identifier)) {
Diag(Tok, diag::err_destructor_tilde_identifier);
return ExprError();
}
// Parse the second type.
UnqualifiedId SecondTypeName;
IdentifierInfo *Name = Tok.getIdentifierInfo();
SourceLocation NameLoc = ConsumeToken();
SecondTypeName.setIdentifier(Name, NameLoc);
// If there is a '<', the second type name is a template-id. Parse
// it as such.
if (Tok.is(tok::less) &&
ParseUnqualifiedIdTemplateId(SS, SourceLocation(),
Name, NameLoc,
false, ObjectType, SecondTypeName,
/*AssumeTemplateName=*/true))
return ExprError();
return Actions.ActOnPseudoDestructorExpr(getCurScope(), Base,
OpLoc, OpKind,
SS, FirstTypeName, CCLoc,
TildeLoc, SecondTypeName,
Tok.is(tok::l_paren));
}
/// ParseCXXBoolLiteral - This handles the C++ Boolean literals.
///
/// boolean-literal: [C++ 2.13.5]
/// 'true'
/// 'false'
ExprResult Parser::ParseCXXBoolLiteral() {
tok::TokenKind Kind = Tok.getKind();
return Actions.ActOnCXXBoolLiteral(ConsumeToken(), Kind);
}
/// ParseThrowExpression - This handles the C++ throw expression.
///
/// throw-expression: [C++ 15]
/// 'throw' assignment-expression[opt]
ExprResult Parser::ParseThrowExpression() {
assert(Tok.is(tok::kw_throw) && "Not throw!");
SourceLocation ThrowLoc = ConsumeToken(); // Eat the throw token.
// If the current token isn't the start of an assignment-expression,
// then the expression is not present. This handles things like:
// "C ? throw : (void)42", which is crazy but legal.
switch (Tok.getKind()) { // FIXME: move this predicate somewhere common.
case tok::semi:
case tok::r_paren:
case tok::r_square:
case tok::r_brace:
case tok::colon:
case tok::comma:
return Actions.ActOnCXXThrow(getCurScope(), ThrowLoc, 0);
default:
ExprResult Expr(ParseAssignmentExpression());
if (Expr.isInvalid()) return Expr;
return Actions.ActOnCXXThrow(getCurScope(), ThrowLoc, Expr.take());
}
}
/// ParseCXXThis - This handles the C++ 'this' pointer.
///
/// C++ 9.3.2: In the body of a non-static member function, the keyword this is
/// a non-lvalue expression whose value is the address of the object for which
/// the function is called.
ExprResult Parser::ParseCXXThis() {
assert(Tok.is(tok::kw_this) && "Not 'this'!");
SourceLocation ThisLoc = ConsumeToken();
return Actions.ActOnCXXThis(ThisLoc);
}
/// ParseCXXTypeConstructExpression - Parse construction of a specified type.
/// Can be interpreted either as function-style casting ("int(x)")
/// or class type construction ("ClassType(x,y,z)")
/// or creation of a value-initialized type ("int()").
/// See [C++ 5.2.3].
///
/// postfix-expression: [C++ 5.2p1]
/// simple-type-specifier '(' expression-list[opt] ')'
/// [C++0x] simple-type-specifier braced-init-list
/// typename-specifier '(' expression-list[opt] ')'
/// [C++0x] typename-specifier braced-init-list
///
ExprResult
Parser::ParseCXXTypeConstructExpression(const DeclSpec &DS) {
Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
ParsedType TypeRep = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo).get();
assert((Tok.is(tok::l_paren) ||
(getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)))
&& "Expected '(' or '{'!");
if (Tok.is(tok::l_brace)) {
ExprResult Init = ParseBraceInitializer();
if (Init.isInvalid())
return Init;
Expr *InitList = Init.take();
return Actions.ActOnCXXTypeConstructExpr(TypeRep, SourceLocation(),
MultiExprArg(&InitList, 1),
SourceLocation());
} else {
BalancedDelimiterTracker T(*this, tok::l_paren);
T.consumeOpen();
ExprVector Exprs;
CommaLocsTy CommaLocs;
if (Tok.isNot(tok::r_paren)) {
if (ParseExpressionList(Exprs, CommaLocs)) {
SkipUntil(tok::r_paren, StopAtSemi);
return ExprError();
}
}
// Match the ')'.
T.consumeClose();
// TypeRep could be null, if it references an invalid typedef.
if (!TypeRep)
return ExprError();
assert((Exprs.size() == 0 || Exprs.size()-1 == CommaLocs.size())&&
"Unexpected number of commas!");
return Actions.ActOnCXXTypeConstructExpr(TypeRep, T.getOpenLocation(),
Exprs,
T.getCloseLocation());
}
}
/// ParseCXXCondition - if/switch/while condition expression.
///
/// condition:
/// expression
/// type-specifier-seq declarator '=' assignment-expression
/// [C++11] type-specifier-seq declarator '=' initializer-clause
/// [C++11] type-specifier-seq declarator braced-init-list
/// [GNU] type-specifier-seq declarator simple-asm-expr[opt] attributes[opt]
/// '=' assignment-expression
///
/// \param ExprOut if the condition was parsed as an expression, the parsed
/// expression.
///
/// \param DeclOut if the condition was parsed as a declaration, the parsed
/// declaration.
///
/// \param Loc The location of the start of the statement that requires this
/// condition, e.g., the "for" in a for loop.
///
/// \param ConvertToBoolean Whether the condition expression should be
/// converted to a boolean value.
///
/// \returns true if there was a parsing, false otherwise.
bool Parser::ParseCXXCondition(ExprResult &ExprOut,
Decl *&DeclOut,
SourceLocation Loc,
bool ConvertToBoolean) {
if (Tok.is(tok::code_completion)) {
Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Condition);
cutOffParsing();
return true;
}
ParsedAttributesWithRange attrs(AttrFactory);
MaybeParseCXX11Attributes(attrs);
if (!isCXXConditionDeclaration()) {
ProhibitAttributes(attrs);
// Parse the expression.
ExprOut = ParseExpression(); // expression
DeclOut = 0;
if (ExprOut.isInvalid())
return true;
// If required, convert to a boolean value.
if (ConvertToBoolean)
ExprOut
= Actions.ActOnBooleanCondition(getCurScope(), Loc, ExprOut.get());
return ExprOut.isInvalid();
}
// type-specifier-seq
DeclSpec DS(AttrFactory);
DS.takeAttributesFrom(attrs);
ParseSpecifierQualifierList(DS);
// declarator
Declarator DeclaratorInfo(DS, Declarator::ConditionContext);
ParseDeclarator(DeclaratorInfo);
// simple-asm-expr[opt]
if (Tok.is(tok::kw_asm)) {
SourceLocation Loc;
ExprResult AsmLabel(ParseSimpleAsm(&Loc));
if (AsmLabel.isInvalid()) {
SkipUntil(tok::semi, StopAtSemi);
return true;
}
DeclaratorInfo.setAsmLabel(AsmLabel.release());
DeclaratorInfo.SetRangeEnd(Loc);
}
// If attributes are present, parse them.
MaybeParseGNUAttributes(DeclaratorInfo);
// Type-check the declaration itself.
DeclResult Dcl = Actions.ActOnCXXConditionDeclaration(getCurScope(),
DeclaratorInfo);
DeclOut = Dcl.get();
ExprOut = ExprError();
// '=' assignment-expression
// If a '==' or '+=' is found, suggest a fixit to '='.
bool CopyInitialization = isTokenEqualOrEqualTypo();
if (CopyInitialization)
ConsumeToken();
ExprResult InitExpr = ExprError();
if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
Diag(Tok.getLocation(),
diag::warn_cxx98_compat_generalized_initializer_lists);
InitExpr = ParseBraceInitializer();
} else if (CopyInitialization) {
InitExpr = ParseAssignmentExpression();
} else if (Tok.is(tok::l_paren)) {
// This was probably an attempt to initialize the variable.
SourceLocation LParen = ConsumeParen(), RParen = LParen;
if (SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch))
RParen = ConsumeParen();
Diag(DeclOut ? DeclOut->getLocation() : LParen,
diag::err_expected_init_in_condition_lparen)
<< SourceRange(LParen, RParen);
} else {
Diag(DeclOut ? DeclOut->getLocation() : Tok.getLocation(),
diag::err_expected_init_in_condition);
}
if (!InitExpr.isInvalid())
Actions.AddInitializerToDecl(DeclOut, InitExpr.take(), !CopyInitialization,
DS.containsPlaceholderType());
else
Actions.ActOnInitializerError(DeclOut);
// FIXME: Build a reference to this declaration? Convert it to bool?
// (This is currently handled by Sema).
Actions.FinalizeDeclaration(DeclOut);
return false;
}
/// ParseCXXSimpleTypeSpecifier - [C++ 7.1.5.2] Simple type specifiers.
/// This should only be called when the current token is known to be part of
/// simple-type-specifier.
///
/// simple-type-specifier:
/// '::'[opt] nested-name-specifier[opt] type-name
/// '::'[opt] nested-name-specifier 'template' simple-template-id [TODO]
/// char
/// wchar_t
/// bool
/// short
/// int
/// long
/// signed
/// unsigned
/// float
/// double
/// void
/// [GNU] typeof-specifier
/// [C++0x] auto [TODO]
///
/// type-name:
/// class-name
/// enum-name
/// typedef-name
///
void Parser::ParseCXXSimpleTypeSpecifier(DeclSpec &DS) {
DS.SetRangeStart(Tok.getLocation());
const char *PrevSpec;
unsigned DiagID;
SourceLocation Loc = Tok.getLocation();
const clang::PrintingPolicy &Policy =
Actions.getASTContext().getPrintingPolicy();
switch (Tok.getKind()) {
case tok::identifier: // foo::bar
case tok::coloncolon: // ::foo::bar
llvm_unreachable("Annotation token should already be formed!");
default:
llvm_unreachable("Not a simple-type-specifier token!");
// type-name
case tok::annot_typename: {
if (getTypeAnnotation(Tok))
DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec, DiagID,
getTypeAnnotation(Tok), Policy);
else
DS.SetTypeSpecError();
DS.SetRangeEnd(Tok.getAnnotationEndLoc());
ConsumeToken();
// Objective-C supports syntax of the form 'id<proto1,proto2>' where 'id'
// is a specific typedef and 'itf<proto1,proto2>' where 'itf' is an
// Objective-C interface. If we don't have Objective-C or a '<', this is
// just a normal reference to a typedef name.
if (Tok.is(tok::less) && getLangOpts().ObjC1)
ParseObjCProtocolQualifiers(DS);
DS.Finish(Diags, PP, Policy);
return;
}
// builtin types
case tok::kw_short:
DS.SetTypeSpecWidth(DeclSpec::TSW_short, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_long:
DS.SetTypeSpecWidth(DeclSpec::TSW_long, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw___int64:
DS.SetTypeSpecWidth(DeclSpec::TSW_longlong, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_signed:
DS.SetTypeSpecSign(DeclSpec::TSS_signed, Loc, PrevSpec, DiagID);
break;
case tok::kw_unsigned:
DS.SetTypeSpecSign(DeclSpec::TSS_unsigned, Loc, PrevSpec, DiagID);
break;
case tok::kw_void:
DS.SetTypeSpecType(DeclSpec::TST_void, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_char:
DS.SetTypeSpecType(DeclSpec::TST_char, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_int:
DS.SetTypeSpecType(DeclSpec::TST_int, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw___int128:
DS.SetTypeSpecType(DeclSpec::TST_int128, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_half:
DS.SetTypeSpecType(DeclSpec::TST_half, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_float:
DS.SetTypeSpecType(DeclSpec::TST_float, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_double:
DS.SetTypeSpecType(DeclSpec::TST_double, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_wchar_t:
DS.SetTypeSpecType(DeclSpec::TST_wchar, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_char16_t:
DS.SetTypeSpecType(DeclSpec::TST_char16, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_char32_t:
DS.SetTypeSpecType(DeclSpec::TST_char32, Loc, PrevSpec, DiagID, Policy);
break;
case tok::kw_bool:
DS.SetTypeSpecType(DeclSpec::TST_bool, Loc, PrevSpec, DiagID, Policy);
break;
case tok::annot_decltype:
case tok::kw_decltype:
DS.SetRangeEnd(ParseDecltypeSpecifier(DS));
return DS.Finish(Diags, PP, Policy);
// GNU typeof support.
case tok::kw_typeof:
ParseTypeofSpecifier(DS);
DS.Finish(Diags, PP, Policy);
return;
}
if (Tok.is(tok::annot_typename))
DS.SetRangeEnd(Tok.getAnnotationEndLoc());
else
DS.SetRangeEnd(Tok.getLocation());
ConsumeToken();
DS.Finish(Diags, PP, Policy);
}
/// ParseCXXTypeSpecifierSeq - Parse a C++ type-specifier-seq (C++
/// [dcl.name]), which is a non-empty sequence of type-specifiers,
/// e.g., "const short int". Note that the DeclSpec is *not* finished
/// by parsing the type-specifier-seq, because these sequences are
/// typically followed by some form of declarator. Returns true and
/// emits diagnostics if this is not a type-specifier-seq, false
/// otherwise.
///
/// type-specifier-seq: [C++ 8.1]
/// type-specifier type-specifier-seq[opt]
///
bool Parser::ParseCXXTypeSpecifierSeq(DeclSpec &DS) {
ParseSpecifierQualifierList(DS, AS_none, DSC_type_specifier);
DS.Finish(Diags, PP, Actions.getASTContext().getPrintingPolicy());
return false;
}
/// \brief Finish parsing a C++ unqualified-id that is a template-id of
/// some form.
///
/// This routine is invoked when a '<' is encountered after an identifier or
/// operator-function-id is parsed by \c ParseUnqualifiedId() to determine
/// whether the unqualified-id is actually a template-id. This routine will
/// then parse the template arguments and form the appropriate template-id to
/// return to the caller.
///
/// \param SS the nested-name-specifier that precedes this template-id, if
/// we're actually parsing a qualified-id.
///
/// \param Name for constructor and destructor names, this is the actual
/// identifier that may be a template-name.
///
/// \param NameLoc the location of the class-name in a constructor or
/// destructor.
///
/// \param EnteringContext whether we're entering the scope of the
/// nested-name-specifier.
///
/// \param ObjectType if this unqualified-id occurs within a member access
/// expression, the type of the base object whose member is being accessed.
///
/// \param Id as input, describes the template-name or operator-function-id
/// that precedes the '<'. If template arguments were parsed successfully,
/// will be updated with the template-id.
///
/// \param AssumeTemplateId When true, this routine will assume that the name
/// refers to a template without performing name lookup to verify.
///
/// \returns true if a parse error occurred, false otherwise.
bool Parser::ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
SourceLocation TemplateKWLoc,
IdentifierInfo *Name,
SourceLocation NameLoc,
bool EnteringContext,
ParsedType ObjectType,
UnqualifiedId &Id,
bool AssumeTemplateId) {
assert((AssumeTemplateId || Tok.is(tok::less)) &&
"Expected '<' to finish parsing a template-id");
TemplateTy Template;
TemplateNameKind TNK = TNK_Non_template;
switch (Id.getKind()) {
case UnqualifiedId::IK_Identifier:
case UnqualifiedId::IK_OperatorFunctionId:
case UnqualifiedId::IK_LiteralOperatorId:
if (AssumeTemplateId) {
TNK = Actions.ActOnDependentTemplateName(getCurScope(), SS, TemplateKWLoc,
Id, ObjectType, EnteringContext,
Template);
if (TNK == TNK_Non_template)
return true;
} else {
bool MemberOfUnknownSpecialization;
TNK = Actions.isTemplateName(getCurScope(), SS,
TemplateKWLoc.isValid(), Id,
ObjectType, EnteringContext, Template,
MemberOfUnknownSpecialization);
if (TNK == TNK_Non_template && MemberOfUnknownSpecialization &&
ObjectType && IsTemplateArgumentList()) {
// We have something like t->getAs<T>(), where getAs is a
// member of an unknown specialization. However, this will only
// parse correctly as a template, so suggest the keyword 'template'
// before 'getAs' and treat this as a dependent template name.
std::string Name;
if (Id.getKind() == UnqualifiedId::IK_Identifier)
Name = Id.Identifier->getName();
else {
Name = "operator ";
if (Id.getKind() == UnqualifiedId::IK_OperatorFunctionId)
Name += getOperatorSpelling(Id.OperatorFunctionId.Operator);
else
Name += Id.Identifier->getName();
}
Diag(Id.StartLocation, diag::err_missing_dependent_template_keyword)
<< Name
<< FixItHint::CreateInsertion(Id.StartLocation, "template ");
TNK = Actions.ActOnDependentTemplateName(getCurScope(),
SS, TemplateKWLoc, Id,
ObjectType, EnteringContext,
Template);
if (TNK == TNK_Non_template)
return true;
}
}
break;
case UnqualifiedId::IK_ConstructorName: {
UnqualifiedId TemplateName;
bool MemberOfUnknownSpecialization;
TemplateName.setIdentifier(Name, NameLoc);
TNK = Actions.isTemplateName(getCurScope(), SS, TemplateKWLoc.isValid(),
TemplateName, ObjectType,
EnteringContext, Template,
MemberOfUnknownSpecialization);
break;
}
case UnqualifiedId::IK_DestructorName: {
UnqualifiedId TemplateName;
bool MemberOfUnknownSpecialization;
TemplateName.setIdentifier(Name, NameLoc);
if (ObjectType) {
TNK = Actions.ActOnDependentTemplateName(getCurScope(),
SS, TemplateKWLoc, TemplateName,
ObjectType, EnteringContext,
Template);
if (TNK == TNK_Non_template)
return true;
} else {
TNK = Actions.isTemplateName(getCurScope(), SS, TemplateKWLoc.isValid(),
TemplateName, ObjectType,
EnteringContext, Template,
MemberOfUnknownSpecialization);
if (TNK == TNK_Non_template && !Id.DestructorName.get()) {
Diag(NameLoc, diag::err_destructor_template_id)
<< Name << SS.getRange();
return true;
}
}
break;
}
default:
return false;
}
if (TNK == TNK_Non_template)
return false;
// Parse the enclosed template argument list.
SourceLocation LAngleLoc, RAngleLoc;
TemplateArgList TemplateArgs;
if (Tok.is(tok::less) &&
ParseTemplateIdAfterTemplateName(Template, Id.StartLocation,
SS, true, LAngleLoc,
TemplateArgs,
RAngleLoc))
return true;
if (Id.getKind() == UnqualifiedId::IK_Identifier ||
Id.getKind() == UnqualifiedId::IK_OperatorFunctionId ||
Id.getKind() == UnqualifiedId::IK_LiteralOperatorId) {
// Form a parsed representation of the template-id to be stored in the
// UnqualifiedId.
TemplateIdAnnotation *TemplateId
= TemplateIdAnnotation::Allocate(TemplateArgs.size(), TemplateIds);
// FIXME: Store name for literal operator too.
if (Id.getKind() == UnqualifiedId::IK_Identifier) {
TemplateId->Name = Id.Identifier;
TemplateId->Operator = OO_None;
TemplateId->TemplateNameLoc = Id.StartLocation;
} else {
TemplateId->Name = 0;
TemplateId->Operator = Id.OperatorFunctionId.Operator;
TemplateId->TemplateNameLoc = Id.StartLocation;
}
TemplateId->SS = SS;
TemplateId->TemplateKWLoc = TemplateKWLoc;
TemplateId->Template = Template;
TemplateId->Kind = TNK;
TemplateId->LAngleLoc = LAngleLoc;
TemplateId->RAngleLoc = RAngleLoc;
ParsedTemplateArgument *Args = TemplateId->getTemplateArgs();
for (unsigned Arg = 0, ArgEnd = TemplateArgs.size();
Arg != ArgEnd; ++Arg)
Args[Arg] = TemplateArgs[Arg];
Id.setTemplateId(TemplateId);
return false;
}
// Bundle the template arguments together.
ASTTemplateArgsPtr TemplateArgsPtr(TemplateArgs);
// Constructor and destructor names.
TypeResult Type
= Actions.ActOnTemplateIdType(SS, TemplateKWLoc,
Template, NameLoc,
LAngleLoc, TemplateArgsPtr, RAngleLoc,
/*IsCtorOrDtorName=*/true);
if (Type.isInvalid())
return true;
if (Id.getKind() == UnqualifiedId::IK_ConstructorName)
Id.setConstructorName(Type.get(), NameLoc, RAngleLoc);
else
Id.setDestructorName(Id.StartLocation, Type.get(), RAngleLoc);
return false;
}
/// \brief Parse an operator-function-id or conversion-function-id as part
/// of a C++ unqualified-id.
///
/// This routine is responsible only for parsing the operator-function-id or
/// conversion-function-id; it does not handle template arguments in any way.
///
/// \code
/// operator-function-id: [C++ 13.5]
/// 'operator' operator
///
/// operator: one of
/// new delete new[] delete[]
/// + - * / % ^ & | ~
/// ! = < > += -= *= /= %=
/// ^= &= |= << >> >>= <<= == !=
/// <= >= && || ++ -- , ->* ->
/// () []
///
/// conversion-function-id: [C++ 12.3.2]
/// operator conversion-type-id
///
/// conversion-type-id:
/// type-specifier-seq conversion-declarator[opt]
///
/// conversion-declarator:
/// ptr-operator conversion-declarator[opt]
/// \endcode
///
/// \param SS The nested-name-specifier that preceded this unqualified-id. If
/// non-empty, then we are parsing the unqualified-id of a qualified-id.
///
/// \param EnteringContext whether we are entering the scope of the
/// nested-name-specifier.
///
/// \param ObjectType if this unqualified-id occurs within a member access
/// expression, the type of the base object whose member is being accessed.
///
/// \param Result on a successful parse, contains the parsed unqualified-id.
///
/// \returns true if parsing fails, false otherwise.
bool Parser::ParseUnqualifiedIdOperator(CXXScopeSpec &SS, bool EnteringContext,
ParsedType ObjectType,
UnqualifiedId &Result) {
assert(Tok.is(tok::kw_operator) && "Expected 'operator' keyword");
// Consume the 'operator' keyword.
SourceLocation KeywordLoc = ConsumeToken();
// Determine what kind of operator name we have.
unsigned SymbolIdx = 0;
SourceLocation SymbolLocations[3];
OverloadedOperatorKind Op = OO_None;
switch (Tok.getKind()) {
case tok::kw_new:
case tok::kw_delete: {
bool isNew = Tok.getKind() == tok::kw_new;
// Consume the 'new' or 'delete'.
SymbolLocations[SymbolIdx++] = ConsumeToken();
// Check for array new/delete.
if (Tok.is(tok::l_square) &&
(!getLangOpts().CPlusPlus11 || NextToken().isNot(tok::l_square))) {
// Consume the '[' and ']'.
BalancedDelimiterTracker T(*this, tok::l_square);
T.consumeOpen();
T.consumeClose();
if (T.getCloseLocation().isInvalid())
return true;
SymbolLocations[SymbolIdx++] = T.getOpenLocation();
SymbolLocations[SymbolIdx++] = T.getCloseLocation();
Op = isNew? OO_Array_New : OO_Array_Delete;
} else {
Op = isNew? OO_New : OO_Delete;
}
break;
}
#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
case tok::Token: \
SymbolLocations[SymbolIdx++] = ConsumeToken(); \
Op = OO_##Name; \
break;
#define OVERLOADED_OPERATOR_MULTI(Name,Spelling,Unary,Binary,MemberOnly)
#include "clang/Basic/OperatorKinds.def"
case tok::l_paren: {
// Consume the '(' and ')'.
BalancedDelimiterTracker T(*this, tok::l_paren);
T.consumeOpen();
T.consumeClose();
if (T.getCloseLocation().isInvalid())
return true;
SymbolLocations[SymbolIdx++] = T.getOpenLocation();
SymbolLocations[SymbolIdx++] = T.getCloseLocation();
Op = OO_Call;
break;
}
case tok::l_square: {
// Consume the '[' and ']'.
BalancedDelimiterTracker T(*this, tok::l_square);
T.consumeOpen();
T.consumeClose();
if (T.getCloseLocation().isInvalid())
return true;
SymbolLocations[SymbolIdx++] = T.getOpenLocation();
SymbolLocations[SymbolIdx++] = T.getCloseLocation();
Op = OO_Subscript;
break;
}
case tok::code_completion: {
// Code completion for the operator name.
Actions.CodeCompleteOperatorName(getCurScope());
cutOffParsing();
// Don't try to parse any further.
return true;
}
default:
break;
}
if (Op != OO_None) {
// We have parsed an operator-function-id.
Result.setOperatorFunctionId(KeywordLoc, Op, SymbolLocations);
return false;
}
// Parse a literal-operator-id.
//
// literal-operator-id: C++11 [over.literal]
// operator string-literal identifier
// operator user-defined-string-literal
if (getLangOpts().CPlusPlus11 && isTokenStringLiteral()) {
Diag(Tok.getLocation(), diag::warn_cxx98_compat_literal_operator);
SourceLocation DiagLoc;
unsigned DiagId = 0;
// We're past translation phase 6, so perform string literal concatenation
// before checking for "".
SmallVector<Token, 4> Toks;
SmallVector<SourceLocation, 4> TokLocs;
while (isTokenStringLiteral()) {
if (!Tok.is(tok::string_literal) && !DiagId) {
// C++11 [over.literal]p1:
// The string-literal or user-defined-string-literal in a
// literal-operator-id shall have no encoding-prefix [...].
DiagLoc = Tok.getLocation();
DiagId = diag::err_literal_operator_string_prefix;
}
Toks.push_back(Tok);
TokLocs.push_back(ConsumeStringToken());
}
StringLiteralParser Literal(Toks.data(), Toks.size(), PP);
if (Literal.hadError)
return true;
// Grab the literal operator's suffix, which will be either the next token
// or a ud-suffix from the string literal.
IdentifierInfo *II = 0;
SourceLocation SuffixLoc;
if (!Literal.getUDSuffix().empty()) {
II = &PP.getIdentifierTable().get(Literal.getUDSuffix());
SuffixLoc =
Lexer::AdvanceToTokenCharacter(TokLocs[Literal.getUDSuffixToken()],
Literal.getUDSuffixOffset(),
PP.getSourceManager(), getLangOpts());
} else if (Tok.is(tok::identifier)) {
II = Tok.getIdentifierInfo();
SuffixLoc = ConsumeToken();
TokLocs.push_back(SuffixLoc);
} else {
Diag(Tok.getLocation(), diag::err_expected) << tok::identifier;
return true;
}
// The string literal must be empty.
if (!Literal.GetString().empty() || Literal.Pascal) {
// C++11 [over.literal]p1:
// The string-literal or user-defined-string-literal in a
// literal-operator-id shall [...] contain no characters
// other than the implicit terminating '\0'.
DiagLoc = TokLocs.front();
DiagId = diag::err_literal_operator_string_not_empty;
}
if (DiagId) {
// This isn't a valid literal-operator-id, but we think we know
// what the user meant. Tell them what they should have written.
SmallString<32> Str;
Str += "\"\" ";
Str += II->getName();
Diag(DiagLoc, DiagId) << FixItHint::CreateReplacement(
SourceRange(TokLocs.front(), TokLocs.back()), Str);
}
Result.setLiteralOperatorId(II, KeywordLoc, SuffixLoc);
return Actions.checkLiteralOperatorId(SS, Result);
}
// Parse a conversion-function-id.
//
// conversion-function-id: [C++ 12.3.2]
// operator conversion-type-id
//
// conversion-type-id:
// type-specifier-seq conversion-declarator[opt]
//
// conversion-declarator:
// ptr-operator conversion-declarator[opt]
// Parse the type-specifier-seq.
DeclSpec DS(AttrFactory);
if (ParseCXXTypeSpecifierSeq(DS)) // FIXME: ObjectType?
return true;
// Parse the conversion-declarator, which is merely a sequence of
// ptr-operators.
Declarator D(DS, Declarator::ConversionIdContext);
ParseDeclaratorInternal(D, /*DirectDeclParser=*/0);
// Finish up the type.
TypeResult Ty = Actions.ActOnTypeName(getCurScope(), D);
if (Ty.isInvalid())
return true;
// Note that this is a conversion-function-id.
Result.setConversionFunctionId(KeywordLoc, Ty.get(),
D.getSourceRange().getEnd());
return false;
}
/// \brief Parse a C++ unqualified-id (or a C identifier), which describes the
/// name of an entity.
///
/// \code
/// unqualified-id: [C++ expr.prim.general]
/// identifier
/// operator-function-id
/// conversion-function-id
/// [C++0x] literal-operator-id [TODO]
/// ~ class-name
/// template-id
///
/// \endcode
///
/// \param SS The nested-name-specifier that preceded this unqualified-id. If
/// non-empty, then we are parsing the unqualified-id of a qualified-id.
///
/// \param EnteringContext whether we are entering the scope of the
/// nested-name-specifier.
///
/// \param AllowDestructorName whether we allow parsing of a destructor name.
///
/// \param AllowConstructorName whether we allow parsing a constructor name.
///
/// \param ObjectType if this unqualified-id occurs within a member access
/// expression, the type of the base object whose member is being accessed.
///
/// \param Result on a successful parse, contains the parsed unqualified-id.
///
/// \returns true if parsing fails, false otherwise.
bool Parser::ParseUnqualifiedId(CXXScopeSpec &SS, bool EnteringContext,
bool AllowDestructorName,
bool AllowConstructorName,
ParsedType ObjectType,
SourceLocation& TemplateKWLoc,
UnqualifiedId &Result) {
// Handle 'A::template B'. This is for template-ids which have not
// already been annotated by ParseOptionalCXXScopeSpecifier().
bool TemplateSpecified = false;
if (getLangOpts().CPlusPlus && Tok.is(tok::kw_template) &&
(ObjectType || SS.isSet())) {
TemplateSpecified = true;
TemplateKWLoc = ConsumeToken();
}
// unqualified-id:
// identifier
// template-id (when it hasn't already been annotated)
if (Tok.is(tok::identifier)) {
// Consume the identifier.
IdentifierInfo *Id = Tok.getIdentifierInfo();
SourceLocation IdLoc = ConsumeToken();
if (!getLangOpts().CPlusPlus) {
// If we're not in C++, only identifiers matter. Record the
// identifier and return.
Result.setIdentifier(Id, IdLoc);
return false;
}
if (AllowConstructorName &&
Actions.isCurrentClassName(*Id, getCurScope(), &SS)) {
// We have parsed a constructor name.
ParsedType Ty = Actions.getTypeName(*Id, IdLoc, getCurScope(),
&SS, false, false,
ParsedType(),
/*IsCtorOrDtorName=*/true,
/*NonTrivialTypeSourceInfo=*/true);
Result.setConstructorName(Ty, IdLoc, IdLoc);
} else {
// We have parsed an identifier.
Result.setIdentifier(Id, IdLoc);
}
// If the next token is a '<', we may have a template.
if (TemplateSpecified || Tok.is(tok::less))
return ParseUnqualifiedIdTemplateId(SS, TemplateKWLoc, Id, IdLoc,
EnteringContext, ObjectType,
Result, TemplateSpecified);
return false;
}
// unqualified-id:
// template-id (already parsed and annotated)
if (Tok.is(tok::annot_template_id)) {
TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
// If the template-name names the current class, then this is a constructor
if (AllowConstructorName && TemplateId->Name &&
Actions.isCurrentClassName(*TemplateId->Name, getCurScope(), &SS)) {
if (SS.isSet()) {
// C++ [class.qual]p2 specifies that a qualified template-name
// is taken as the constructor name where a constructor can be
// declared. Thus, the template arguments are extraneous, so
// complain about them and remove them entirely.
Diag(TemplateId->TemplateNameLoc,
diag::err_out_of_line_constructor_template_id)
<< TemplateId->Name
<< FixItHint::CreateRemoval(
SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc));
ParsedType Ty = Actions.getTypeName(*TemplateId->Name,
TemplateId->TemplateNameLoc,
getCurScope(),
&SS, false, false,
ParsedType(),
/*IsCtorOrDtorName=*/true,
/*NontrivialTypeSourceInfo=*/true);
Result.setConstructorName(Ty, TemplateId->TemplateNameLoc,
TemplateId->RAngleLoc);
ConsumeToken();
return false;
}
Result.setConstructorTemplateId(TemplateId);
ConsumeToken();
return false;
}
// We have already parsed a template-id; consume the annotation token as
// our unqualified-id.
Result.setTemplateId(TemplateId);
TemplateKWLoc = TemplateId->TemplateKWLoc;
ConsumeToken();
return false;
}
// unqualified-id:
// operator-function-id
// conversion-function-id
if (Tok.is(tok::kw_operator)) {
if (ParseUnqualifiedIdOperator(SS, EnteringContext, ObjectType, Result))
return true;
// If we have an operator-function-id or a literal-operator-id and the next
// token is a '<', we may have a
//
// template-id:
// operator-function-id < template-argument-list[opt] >
if ((Result.getKind() == UnqualifiedId::IK_OperatorFunctionId ||
Result.getKind() == UnqualifiedId::IK_LiteralOperatorId) &&
(TemplateSpecified || Tok.is(tok::less)))
return ParseUnqualifiedIdTemplateId(SS, TemplateKWLoc,
0, SourceLocation(),
EnteringContext, ObjectType,
Result, TemplateSpecified);
return false;
}
if (getLangOpts().CPlusPlus &&
(AllowDestructorName || SS.isSet()) && Tok.is(tok::tilde)) {
// C++ [expr.unary.op]p10:
// There is an ambiguity in the unary-expression ~X(), where X is a
// class-name. The ambiguity is resolved in favor of treating ~ as a
// unary complement rather than treating ~X as referring to a destructor.
// Parse the '~'.
SourceLocation TildeLoc = ConsumeToken();
if (SS.isEmpty() && Tok.is(tok::kw_decltype)) {
DeclSpec DS(AttrFactory);
SourceLocation EndLoc = ParseDecltypeSpecifier(DS);
if (ParsedType Type = Actions.getDestructorType(DS, ObjectType)) {
Result.setDestructorName(TildeLoc, Type, EndLoc);
return false;
}
return true;
}
// Parse the class-name.
if (Tok.isNot(tok::identifier)) {
Diag(Tok, diag::err_destructor_tilde_identifier);
return true;
}
// Parse the class-name (or template-name in a simple-template-id).
IdentifierInfo *ClassName = Tok.getIdentifierInfo();
SourceLocation ClassNameLoc = ConsumeToken();
if (TemplateSpecified || Tok.is(tok::less)) {
Result.setDestructorName(TildeLoc, ParsedType(), ClassNameLoc);
return ParseUnqualifiedIdTemplateId(SS, TemplateKWLoc,
ClassName, ClassNameLoc,
EnteringContext, ObjectType,
Result, TemplateSpecified);
}
// Note that this is a destructor name.
ParsedType Ty = Actions.getDestructorName(TildeLoc, *ClassName,
ClassNameLoc, getCurScope(),
SS, ObjectType,
EnteringContext);
if (!Ty)
return true;
Result.setDestructorName(TildeLoc, Ty, ClassNameLoc);
return false;
}
Diag(Tok, diag::err_expected_unqualified_id)
<< getLangOpts().CPlusPlus;
return true;
}
/// ParseCXXNewExpression - Parse a C++ new-expression. New is used to allocate
/// memory in a typesafe manner and call constructors.
///
/// This method is called to parse the new expression after the optional :: has
/// been already parsed. If the :: was present, "UseGlobal" is true and "Start"
/// is its location. Otherwise, "Start" is the location of the 'new' token.
///
/// new-expression:
/// '::'[opt] 'new' new-placement[opt] new-type-id
/// new-initializer[opt]
/// '::'[opt] 'new' new-placement[opt] '(' type-id ')'
/// new-initializer[opt]
///
/// new-placement:
/// '(' expression-list ')'
///
/// new-type-id:
/// type-specifier-seq new-declarator[opt]
/// [GNU] attributes type-specifier-seq new-declarator[opt]
///
/// new-declarator:
/// ptr-operator new-declarator[opt]
/// direct-new-declarator
///
/// new-initializer:
/// '(' expression-list[opt] ')'
/// [C++0x] braced-init-list
///
ExprResult
Parser::ParseCXXNewExpression(bool UseGlobal, SourceLocation Start) {
assert(Tok.is(tok::kw_new) && "expected 'new' token");
ConsumeToken(); // Consume 'new'
// A '(' now can be a new-placement or the '(' wrapping the type-id in the
// second form of new-expression. It can't be a new-type-id.
ExprVector PlacementArgs;
SourceLocation PlacementLParen, PlacementRParen;
SourceRange TypeIdParens;
DeclSpec DS(AttrFactory);
Declarator DeclaratorInfo(DS, Declarator::CXXNewContext);
if (Tok.is(tok::l_paren)) {
// If it turns out to be a placement, we change the type location.
BalancedDelimiterTracker T(*this, tok::l_paren);
T.consumeOpen();
PlacementLParen = T.getOpenLocation();
if (ParseExpressionListOrTypeId(PlacementArgs, DeclaratorInfo)) {
SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch);
return ExprError();
}
T.consumeClose();
PlacementRParen = T.getCloseLocation();
if (PlacementRParen.isInvalid()) {
SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch);
return ExprError();
}
if (PlacementArgs.empty()) {
// Reset the placement locations. There was no placement.
TypeIdParens = T.getRange();
PlacementLParen = PlacementRParen = SourceLocation();
} else {
// We still need the type.
if (Tok.is(tok::l_paren)) {
BalancedDelimiterTracker T(*this, tok::l_paren);
T.consumeOpen();
MaybeParseGNUAttributes(DeclaratorInfo);
ParseSpecifierQualifierList(DS);
DeclaratorInfo.SetSourceRange(DS.getSourceRange());
ParseDeclarator(DeclaratorInfo);
T.consumeClose();
TypeIdParens = T.getRange();
} else {
MaybeParseGNUAttributes(DeclaratorInfo);
if (ParseCXXTypeSpecifierSeq(DS))
DeclaratorInfo.setInvalidType(true);
else {
DeclaratorInfo.SetSourceRange(DS.getSourceRange());
ParseDeclaratorInternal(DeclaratorInfo,
&Parser::ParseDirectNewDeclarator);
}
}
}
} else {
// A new-type-id is a simplified type-id, where essentially the
// direct-declarator is replaced by a direct-new-declarator.
MaybeParseGNUAttributes(DeclaratorInfo);
if (ParseCXXTypeSpecifierSeq(DS))
DeclaratorInfo.setInvalidType(true);
else {
DeclaratorInfo.SetSourceRange(DS.getSourceRange());
ParseDeclaratorInternal(DeclaratorInfo,
&Parser::ParseDirectNewDeclarator);
}
}
if (DeclaratorInfo.isInvalidType()) {
SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch);
return ExprError();
}
ExprResult Initializer;
if (Tok.is(tok::l_paren)) {
SourceLocation ConstructorLParen, ConstructorRParen;
ExprVector ConstructorArgs;
BalancedDelimiterTracker T(*this, tok::l_paren);
T.consumeOpen();
ConstructorLParen = T.getOpenLocation();
if (Tok.isNot(tok::r_paren)) {
CommaLocsTy CommaLocs;
if (ParseExpressionList(ConstructorArgs, CommaLocs)) {
SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch);
return ExprError();
}
}
T.consumeClose();
ConstructorRParen = T.getCloseLocation();
if (ConstructorRParen.isInvalid()) {
SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch);
return ExprError();
}
Initializer = Actions.ActOnParenListExpr(ConstructorLParen,
ConstructorRParen,
ConstructorArgs);
} else if (Tok.is(tok::l_brace) && getLangOpts().CPlusPlus11) {
Diag(Tok.getLocation(),
diag::warn_cxx98_compat_generalized_initializer_lists);
Initializer = ParseBraceInitializer();
}
if (Initializer.isInvalid())
return Initializer;
return Actions.ActOnCXXNew(Start, UseGlobal, PlacementLParen,
PlacementArgs, PlacementRParen,
TypeIdParens, DeclaratorInfo, Initializer.take());
}
/// ParseDirectNewDeclarator - Parses a direct-new-declarator. Intended to be
/// passed to ParseDeclaratorInternal.
///
/// direct-new-declarator:
/// '[' expression ']'
/// direct-new-declarator '[' constant-expression ']'
///
void Parser::ParseDirectNewDeclarator(Declarator &D) {
// Parse the array dimensions.
bool first = true;
while (Tok.is(tok::l_square)) {
// An array-size expression can't start with a lambda.
if (CheckProhibitedCXX11Attribute())
continue;
BalancedDelimiterTracker T(*this, tok::l_square);
T.consumeOpen();
ExprResult Size(first ? ParseExpression()
: ParseConstantExpression());
if (Size.isInvalid()) {
// Recover
SkipUntil(tok::r_square, StopAtSemi);
return;
}
first = false;
T.consumeClose();
// Attributes here appertain to the array type. C++11 [expr.new]p5.
ParsedAttributes Attrs(AttrFactory);
MaybeParseCXX11Attributes(Attrs);
D.AddTypeInfo(DeclaratorChunk::getArray(0,
/*static=*/false, /*star=*/false,
Size.release(),
T.getOpenLocation(),
T.getCloseLocation()),
Attrs, T.getCloseLocation());
if (T.getCloseLocation().isInvalid())
return;
}
}
/// ParseExpressionListOrTypeId - Parse either an expression-list or a type-id.
/// This ambiguity appears in the syntax of the C++ new operator.
///
/// new-expression:
/// '::'[opt] 'new' new-placement[opt] '(' type-id ')'
/// new-initializer[opt]
///
/// new-placement:
/// '(' expression-list ')'
///
bool Parser::ParseExpressionListOrTypeId(
SmallVectorImpl<Expr*> &PlacementArgs,
Declarator &D) {
// The '(' was already consumed.
if (isTypeIdInParens()) {
ParseSpecifierQualifierList(D.getMutableDeclSpec());
D.SetSourceRange(D.getDeclSpec().getSourceRange());
ParseDeclarator(D);
return D.isInvalidType();
}
// It's not a type, it has to be an expression list.
// Discard the comma locations - ActOnCXXNew has enough parameters.
CommaLocsTy CommaLocs;
return ParseExpressionList(PlacementArgs, CommaLocs);
}
/// ParseCXXDeleteExpression - Parse a C++ delete-expression. Delete is used
/// to free memory allocated by new.
///
/// This method is called to parse the 'delete' expression after the optional
/// '::' has been already parsed. If the '::' was present, "UseGlobal" is true
/// and "Start" is its location. Otherwise, "Start" is the location of the
/// 'delete' token.
///
/// delete-expression:
/// '::'[opt] 'delete' cast-expression
/// '::'[opt] 'delete' '[' ']' cast-expression
ExprResult
Parser::ParseCXXDeleteExpression(bool UseGlobal, SourceLocation Start) {
assert(Tok.is(tok::kw_delete) && "Expected 'delete' keyword");
ConsumeToken(); // Consume 'delete'
// Array delete?
bool ArrayDelete = false;
if (Tok.is(tok::l_square) && NextToken().is(tok::r_square)) {
// C++11 [expr.delete]p1:
// Whenever the delete keyword is followed by empty square brackets, it
// shall be interpreted as [array delete].
// [Footnote: A lambda expression with a lambda-introducer that consists
// of empty square brackets can follow the delete keyword if
// the lambda expression is enclosed in parentheses.]
// FIXME: Produce a better diagnostic if the '[]' is unambiguously a
// lambda-introducer.
ArrayDelete = true;
BalancedDelimiterTracker T(*this, tok::l_square);
T.consumeOpen();
T.consumeClose();
if (T.getCloseLocation().isInvalid())
return ExprError();
}
ExprResult Operand(ParseCastExpression(false));
if (Operand.isInvalid())
return Operand;
return Actions.ActOnCXXDelete(Start, UseGlobal, ArrayDelete, Operand.take());
}
static TypeTrait TypeTraitFromTokKind(tok::TokenKind kind) {
switch (kind) {
default: llvm_unreachable("Not a known type trait");
#define TYPE_TRAIT_1(Spelling, Name, Key) \
case tok::kw_ ## Spelling: return UTT_ ## Name;
#define TYPE_TRAIT_2(Spelling, Name, Key) \
case tok::kw_ ## Spelling: return BTT_ ## Name;
#include "clang/Basic/TokenKinds.def"
#define TYPE_TRAIT_N(Spelling, Name, Key) \
case tok::kw_ ## Spelling: return TT_ ## Name;
#include "clang/Basic/TokenKinds.def"
}
}
static ArrayTypeTrait ArrayTypeTraitFromTokKind(tok::TokenKind kind) {
switch(kind) {
default: llvm_unreachable("Not a known binary type trait");
case tok::kw___array_rank: return ATT_ArrayRank;
case tok::kw___array_extent: return ATT_ArrayExtent;
}
}
static ExpressionTrait ExpressionTraitFromTokKind(tok::TokenKind kind) {
switch(kind) {
default: llvm_unreachable("Not a known unary expression trait.");
case tok::kw___is_lvalue_expr: return ET_IsLValueExpr;
case tok::kw___is_rvalue_expr: return ET_IsRValueExpr;
}
}
static unsigned TypeTraitArity(tok::TokenKind kind) {
switch (kind) {
default: llvm_unreachable("Not a known type trait");
#define TYPE_TRAIT(N,Spelling,K) case tok::kw_##Spelling: return N;
#include "clang/Basic/TokenKinds.def"
}
}
/// \brief Parse the built-in type-trait pseudo-functions that allow
/// implementation of the TR1/C++11 type traits templates.
///
/// primary-expression:
/// unary-type-trait '(' type-id ')'
/// binary-type-trait '(' type-id ',' type-id ')'
/// type-trait '(' type-id-seq ')'
///
/// type-id-seq:
/// type-id ...[opt] type-id-seq[opt]
///
ExprResult Parser::ParseTypeTrait() {
tok::TokenKind Kind = Tok.getKind();
unsigned Arity = TypeTraitArity(Kind);
SourceLocation Loc = ConsumeToken();
BalancedDelimiterTracker Parens(*this, tok::l_paren);
if (Parens.expectAndConsume())
return ExprError();
SmallVector<ParsedType, 2> Args;
do {
// Parse the next type.
TypeResult Ty = ParseTypeName();
if (Ty.isInvalid()) {
Parens.skipToEnd();
return ExprError();
}
// Parse the ellipsis, if present.
if (Tok.is(tok::ellipsis)) {
Ty = Actions.ActOnPackExpansion(Ty.get(), ConsumeToken());
if (Ty.isInvalid()) {
Parens.skipToEnd();
return ExprError();
}
}
// Add this type to the list of arguments.
Args.push_back(Ty.get());
} while (TryConsumeToken(tok::comma));
if (Parens.consumeClose())
return ExprError();
SourceLocation EndLoc = Parens.getCloseLocation();
if (Arity && Args.size() != Arity) {
Diag(EndLoc, diag::err_type_trait_arity)
<< Arity << 0 << (Arity > 1) << (int)Args.size() << SourceRange(Loc);
return ExprError();
}
if (!Arity && Args.empty()) {
Diag(EndLoc, diag::err_type_trait_arity)
<< 1 << 1 << 1 << (int)Args.size() << SourceRange(Loc);
return ExprError();
}
return Actions.ActOnTypeTrait(TypeTraitFromTokKind(Kind), Loc, Args, EndLoc);
}
/// ParseArrayTypeTrait - Parse the built-in array type-trait
/// pseudo-functions.
///
/// primary-expression:
/// [Embarcadero] '__array_rank' '(' type-id ')'
/// [Embarcadero] '__array_extent' '(' type-id ',' expression ')'
///
ExprResult Parser::ParseArrayTypeTrait() {
ArrayTypeTrait ATT = ArrayTypeTraitFromTokKind(Tok.getKind());
SourceLocation Loc = ConsumeToken();
BalancedDelimiterTracker T(*this, tok::l_paren);
if (T.expectAndConsume())
return ExprError();
TypeResult Ty = ParseTypeName();
if (Ty.isInvalid()) {
SkipUntil(tok::comma, StopAtSemi);
SkipUntil(tok::r_paren, StopAtSemi);
return ExprError();
}
switch (ATT) {
case ATT_ArrayRank: {
T.consumeClose();
return Actions.ActOnArrayTypeTrait(ATT, Loc, Ty.get(), NULL,
T.getCloseLocation());
}
case ATT_ArrayExtent: {
if (ExpectAndConsume(tok::comma)) {
SkipUntil(tok::r_paren, StopAtSemi);
return ExprError();
}
ExprResult DimExpr = ParseExpression();
T.consumeClose();
return Actions.ActOnArrayTypeTrait(ATT, Loc, Ty.get(), DimExpr.get(),
T.getCloseLocation());
}
}
llvm_unreachable("Invalid ArrayTypeTrait!");
}
/// ParseExpressionTrait - Parse built-in expression-trait
/// pseudo-functions like __is_lvalue_expr( xxx ).
///
/// primary-expression:
/// [Embarcadero] expression-trait '(' expression ')'
///
ExprResult Parser::ParseExpressionTrait() {
ExpressionTrait ET = ExpressionTraitFromTokKind(Tok.getKind());
SourceLocation Loc = ConsumeToken();
BalancedDelimiterTracker T(*this, tok::l_paren);
if (T.expectAndConsume())
return ExprError();
ExprResult Expr = ParseExpression();
T.consumeClose();
return Actions.ActOnExpressionTrait(ET, Loc, Expr.get(),
T.getCloseLocation());
}
/// ParseCXXAmbiguousParenExpression - We have parsed the left paren of a
/// parenthesized ambiguous type-id. This uses tentative parsing to disambiguate
/// based on the context past the parens.
ExprResult
Parser::ParseCXXAmbiguousParenExpression(ParenParseOption &ExprType,
ParsedType &CastTy,
BalancedDelimiterTracker &Tracker) {
assert(getLangOpts().CPlusPlus && "Should only be called for C++!");
assert(ExprType == CastExpr && "Compound literals are not ambiguous!");
assert(isTypeIdInParens() && "Not a type-id!");
ExprResult Result(true);
CastTy = ParsedType();
// We need to disambiguate a very ugly part of the C++ syntax:
//
// (T())x; - type-id
// (T())*x; - type-id
// (T())/x; - expression
// (T()); - expression
//
// The bad news is that we cannot use the specialized tentative parser, since
// it can only verify that the thing inside the parens can be parsed as
// type-id, it is not useful for determining the context past the parens.
//
// The good news is that the parser can disambiguate this part without
// making any unnecessary Action calls.
//
// It uses a scheme similar to parsing inline methods. The parenthesized
// tokens are cached, the context that follows is determined (possibly by
// parsing a cast-expression), and then we re-introduce the cached tokens
// into the token stream and parse them appropriately.
ParenParseOption ParseAs;
CachedTokens Toks;
// Store the tokens of the parentheses. We will parse them after we determine
// the context that follows them.
if (!ConsumeAndStoreUntil(tok::r_paren, Toks)) {
// We didn't find the ')' we expected.
Tracker.consumeClose();
return ExprError();
}
if (Tok.is(tok::l_brace)) {
ParseAs = CompoundLiteral;
} else {
bool NotCastExpr;
// FIXME: Special-case ++ and --: "(S())++;" is not a cast-expression
if (Tok.is(tok::l_paren) && NextToken().is(tok::r_paren)) {
NotCastExpr = true;
} else {
// Try parsing the cast-expression that may follow.
// If it is not a cast-expression, NotCastExpr will be true and no token
// will be consumed.
Result = ParseCastExpression(false/*isUnaryExpression*/,
false/*isAddressofOperand*/,
NotCastExpr,
// type-id has priority.
IsTypeCast);
}
// If we parsed a cast-expression, it's really a type-id, otherwise it's
// an expression.
ParseAs = NotCastExpr ? SimpleExpr : CastExpr;
}
// The current token should go after the cached tokens.
Toks.push_back(Tok);
// Re-enter the stored parenthesized tokens into the token stream, so we may
// parse them now.
PP.EnterTokenStream(Toks.data(), Toks.size(),
true/*DisableMacroExpansion*/, false/*OwnsTokens*/);
// Drop the current token and bring the first cached one. It's the same token
// as when we entered this function.
ConsumeAnyToken();
if (ParseAs >= CompoundLiteral) {
// Parse the type declarator.
DeclSpec DS(AttrFactory);
ParseSpecifierQualifierList(DS);
Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
ParseDeclarator(DeclaratorInfo);
// Match the ')'.
Tracker.consumeClose();
if (ParseAs == CompoundLiteral) {
ExprType = CompoundLiteral;
TypeResult Ty = ParseTypeName();
return ParseCompoundLiteralExpression(Ty.get(),
Tracker.getOpenLocation(),
Tracker.getCloseLocation());
}
// We parsed '(' type-id ')' and the thing after it wasn't a '{'.
assert(ParseAs == CastExpr);
if (DeclaratorInfo.isInvalidType())
return ExprError();
// Result is what ParseCastExpression returned earlier.
if (!Result.isInvalid())
Result = Actions.ActOnCastExpr(getCurScope(), Tracker.getOpenLocation(),
DeclaratorInfo, CastTy,
Tracker.getCloseLocation(), Result.take());
return Result;
}
// Not a compound literal, and not followed by a cast-expression.
assert(ParseAs == SimpleExpr);
ExprType = SimpleExpr;
Result = ParseExpression();
if (!Result.isInvalid() && Tok.is(tok::r_paren))
Result = Actions.ActOnParenExpr(Tracker.getOpenLocation(),
Tok.getLocation(), Result.take());
// Match the ')'.
if (Result.isInvalid()) {
SkipUntil(tok::r_paren, StopAtSemi);
return ExprError();
}
Tracker.consumeClose();
return Result;
}