void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
Declarator &ParamInfo,
Scope *CurScope) {
// Determine if we're within a context where we know that the lambda will
// be dependent, because there are template parameters in scope.
bool KnownDependent = false;
if (Scope *TmplScope = CurScope->getTemplateParamParent())
if (!TmplScope->decl_empty())
KnownDependent = true;
CXXRecordDecl *Class = createLambdaClosureType(Intro.Range, KnownDependent);
// Determine the signature of the call operator.
TypeSourceInfo *MethodTyInfo;
bool ExplicitParams = true;
bool ExplicitResultType = true;
bool ContainsUnexpandedParameterPack = false;
SourceLocation EndLoc;
llvm::ArrayRef<ParmVarDecl *> Params;
if (ParamInfo.getNumTypeObjects() == 0) {
// C++11 [expr.prim.lambda]p4:
// If a lambda-expression does not include a lambda-declarator, it is as
// if the lambda-declarator were ().
FunctionProtoType::ExtProtoInfo EPI;
EPI.HasTrailingReturn = true;
EPI.TypeQuals |= DeclSpec::TQ_const;
QualType MethodTy = Context.getFunctionType(Context.DependentTy,
/*Args=*/0, /*NumArgs=*/0, EPI);
MethodTyInfo = Context.getTrivialTypeSourceInfo(MethodTy);
ExplicitParams = false;
ExplicitResultType = false;
EndLoc = Intro.Range.getEnd();
} else {
assert(ParamInfo.isFunctionDeclarator() &&
"lambda-declarator is a function");
DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getFunctionTypeInfo();
// C++11 [expr.prim.lambda]p5:
// This function call operator is declared const (9.3.1) if and only if
// the lambda-expression's parameter-declaration-clause is not followed
// by mutable. It is neither virtual nor declared volatile. [...]
if (!FTI.hasMutableQualifier())
FTI.TypeQuals |= DeclSpec::TQ_const;
MethodTyInfo = GetTypeForDeclarator(ParamInfo, CurScope);
assert(MethodTyInfo && "no type from lambda-declarator");
EndLoc = ParamInfo.getSourceRange().getEnd();
ExplicitResultType
= MethodTyInfo->getType()->getAs<FunctionType>()->getResultType()
!= Context.DependentTy;
TypeLoc TL = MethodTyInfo->getTypeLoc();
FunctionProtoTypeLoc Proto = cast<FunctionProtoTypeLoc>(TL);
Params = llvm::ArrayRef<ParmVarDecl *>(Proto.getParmArray(),
Proto.getNumArgs());
// Check for unexpanded parameter packs in the method type.
if (MethodTyInfo->getType()->containsUnexpandedParameterPack())
ContainsUnexpandedParameterPack = true;
}
CXXMethodDecl *Method = startLambdaDefinition(Class, Intro.Range,
MethodTyInfo, EndLoc, Params);
if (ExplicitParams)
CheckCXXDefaultArguments(Method);
// Attributes on the lambda apply to the method.
ProcessDeclAttributes(CurScope, Method, ParamInfo);
// Introduce the function call operator as the current declaration context.
PushDeclContext(CurScope, Method);
// Introduce the lambda scope.
LambdaScopeInfo *LSI
= enterLambdaScope(Method, Intro.Range, Intro.Default, ExplicitParams,
ExplicitResultType,
(Method->getTypeQualifiers() & Qualifiers::Const) == 0);
// Handle explicit captures.
SourceLocation PrevCaptureLoc
= Intro.Default == LCD_None? Intro.Range.getBegin() : Intro.DefaultLoc;
for (llvm::SmallVector<LambdaCapture, 4>::const_iterator
C = Intro.Captures.begin(),
E = Intro.Captures.end();
C != E;
PrevCaptureLoc = C->Loc, ++C) {
if (C->Kind == LCK_This) {
// C++11 [expr.prim.lambda]p8:
// An identifier or this shall not appear more than once in a
// lambda-capture.
if (LSI->isCXXThisCaptured()) {
Diag(C->Loc, diag::err_capture_more_than_once)
<< "'this'"
<< SourceRange(LSI->getCXXThisCapture().getLocation())
<< FixItHint::CreateRemoval(
SourceRange(PP.getLocForEndOfToken(PrevCaptureLoc), C->Loc));
continue;
}
// C++11 [expr.prim.lambda]p8:
// If a lambda-capture includes a capture-default that is =, the
// lambda-capture shall not contain this [...].
if (Intro.Default == LCD_ByCopy) {
Diag(C->Loc, diag::err_this_capture_with_copy_default)
<< FixItHint::CreateRemoval(
SourceRange(PP.getLocForEndOfToken(PrevCaptureLoc), C->Loc));
continue;
}
// C++11 [expr.prim.lambda]p12:
// If this is captured by a local lambda expression, its nearest
// enclosing function shall be a non-static member function.
QualType ThisCaptureType = getCurrentThisType();
if (ThisCaptureType.isNull()) {
Diag(C->Loc, diag::err_this_capture) << true;
continue;
}
CheckCXXThisCapture(C->Loc, /*Explicit=*/true);
continue;
}
assert(C->Id && "missing identifier for capture");
// C++11 [expr.prim.lambda]p8:
// If a lambda-capture includes a capture-default that is &, the
// identifiers in the lambda-capture shall not be preceded by &.
// If a lambda-capture includes a capture-default that is =, [...]
// each identifier it contains shall be preceded by &.
if (C->Kind == LCK_ByRef && Intro.Default == LCD_ByRef) {
Diag(C->Loc, diag::err_reference_capture_with_reference_default)
<< FixItHint::CreateRemoval(
SourceRange(PP.getLocForEndOfToken(PrevCaptureLoc), C->Loc));
continue;
} else if (C->Kind == LCK_ByCopy && Intro.Default == LCD_ByCopy) {
Diag(C->Loc, diag::err_copy_capture_with_copy_default)
<< FixItHint::CreateRemoval(
SourceRange(PP.getLocForEndOfToken(PrevCaptureLoc), C->Loc));
continue;
}
DeclarationNameInfo Name(C->Id, C->Loc);
LookupResult R(*this, Name, LookupOrdinaryName);
LookupName(R, CurScope);
if (R.isAmbiguous())
continue;
if (R.empty()) {
// FIXME: Disable corrections that would add qualification?
CXXScopeSpec ScopeSpec;
DeclFilterCCC<VarDecl> Validator;
if (DiagnoseEmptyLookup(CurScope, ScopeSpec, R, Validator))
continue;
}
// C++11 [expr.prim.lambda]p10:
// The identifiers in a capture-list are looked up using the usual rules
// for unqualified name lookup (3.4.1); each such lookup shall find a
// variable with automatic storage duration declared in the reaching
// scope of the local lambda expression.
//
// Note that the 'reaching scope' check happens in tryCaptureVariable().
VarDecl *Var = R.getAsSingle<VarDecl>();
if (!Var) {
Diag(C->Loc, diag::err_capture_does_not_name_variable) << C->Id;
continue;
}
if (!Var->hasLocalStorage()) {
Diag(C->Loc, diag::err_capture_non_automatic_variable) << C->Id;
Diag(Var->getLocation(), diag::note_previous_decl) << C->Id;
continue;
}
// C++11 [expr.prim.lambda]p8:
// An identifier or this shall not appear more than once in a
// lambda-capture.
if (LSI->isCaptured(Var)) {
Diag(C->Loc, diag::err_capture_more_than_once)
<< C->Id
<< SourceRange(LSI->getCapture(Var).getLocation())
<< FixItHint::CreateRemoval(
SourceRange(PP.getLocForEndOfToken(PrevCaptureLoc), C->Loc));
continue;
}
// C++11 [expr.prim.lambda]p23:
// A capture followed by an ellipsis is a pack expansion (14.5.3).
SourceLocation EllipsisLoc;
if (C->EllipsisLoc.isValid()) {
if (Var->isParameterPack()) {
EllipsisLoc = C->EllipsisLoc;
} else {
Diag(C->EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
<< SourceRange(C->Loc);
// Just ignore the ellipsis.
}
} else if (Var->isParameterPack()) {
ContainsUnexpandedParameterPack = true;
}
TryCaptureKind Kind = C->Kind == LCK_ByRef ? TryCapture_ExplicitByRef :
TryCapture_ExplicitByVal;
tryCaptureVariable(Var, C->Loc, Kind, EllipsisLoc);
}
finishLambdaExplicitCaptures(LSI);
LSI->ContainsUnexpandedParameterPack = ContainsUnexpandedParameterPack;
// Add lambda parameters into scope.
addLambdaParameters(Method, CurScope);
// Enter a new evaluation context to insulate the lambda from any
// cleanups from the enclosing full-expression.
PushExpressionEvaluationContext(PotentiallyEvaluated);
}
void Parser::ParseLexedMethodDeclaration(LateParsedMethodDeclaration &LM) {
// If this is a member template, introduce the template parameter scope.
ParseScope TemplateScope(this, Scope::TemplateParamScope, LM.TemplateScope);
TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
if (LM.TemplateScope) {
Actions.ActOnReenterTemplateScope(getCurScope(), LM.Method);
++CurTemplateDepthTracker;
}
// Start the delayed C++ method declaration
Actions.ActOnStartDelayedCXXMethodDeclaration(getCurScope(), LM.Method);
// Introduce the parameters into scope and parse their default
// arguments.
ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope |
Scope::FunctionDeclarationScope | Scope::DeclScope);
for (unsigned I = 0, N = LM.DefaultArgs.size(); I != N; ++I) {
auto Param = LM.DefaultArgs[I].Param;
// Introduce the parameter into scope.
Actions.ActOnDelayedCXXMethodParameter(getCurScope(), Param);
if (CachedTokens *Toks = LM.DefaultArgs[I].Toks) {
// Mark the end of the default argument so that we know when to stop when
// we parse it later on.
Token LastDefaultArgToken = Toks->back();
Token DefArgEnd;
DefArgEnd.startToken();
DefArgEnd.setKind(tok::eof);
DefArgEnd.setLocation(LastDefaultArgToken.getLocation().getLocWithOffset(
LastDefaultArgToken.getLength()));
DefArgEnd.setEofData(Param);
Toks->push_back(DefArgEnd);
// Parse the default argument from its saved token stream.
Toks->push_back(Tok); // So that the current token doesn't get lost
PP.EnterTokenStream(&Toks->front(), Toks->size(), true, false);
// Consume the previously-pushed token.
ConsumeAnyToken();
// Consume the '='.
assert(Tok.is(tok::equal) && "Default argument not starting with '='");
SourceLocation EqualLoc = ConsumeToken();
// The argument isn't actually potentially evaluated unless it is
// used.
EnterExpressionEvaluationContext Eval(Actions,
Sema::PotentiallyEvaluatedIfUsed,
Param);
ExprResult DefArgResult;
if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
DefArgResult = ParseBraceInitializer();
} else
DefArgResult = ParseAssignmentExpression();
DefArgResult = Actions.CorrectDelayedTyposInExpr(DefArgResult);
if (DefArgResult.isInvalid()) {
Actions.ActOnParamDefaultArgumentError(Param, EqualLoc);
} else {
if (Tok.isNot(tok::eof) || Tok.getEofData() != Param) {
// The last two tokens are the terminator and the saved value of
// Tok; the last token in the default argument is the one before
// those.
assert(Toks->size() >= 3 && "expected a token in default arg");
Diag(Tok.getLocation(), diag::err_default_arg_unparsed)
<< SourceRange(Tok.getLocation(),
(*Toks)[Toks->size() - 3].getLocation());
}
Actions.ActOnParamDefaultArgument(Param, EqualLoc,
DefArgResult.get());
}
// There could be leftover tokens (e.g. because of an error).
// Skip through until we reach the 'end of default argument' token.
while (Tok.isNot(tok::eof))
ConsumeAnyToken();
if (Tok.is(tok::eof) && Tok.getEofData() == Param)
ConsumeAnyToken();
delete Toks;
LM.DefaultArgs[I].Toks = nullptr;
}
}
// Parse a delayed exception-specification, if there is one.
if (CachedTokens *Toks = LM.ExceptionSpecTokens) {
// Add the 'stop' token.
Token LastExceptionSpecToken = Toks->back();
Token ExceptionSpecEnd;
ExceptionSpecEnd.startToken();
ExceptionSpecEnd.setKind(tok::eof);
ExceptionSpecEnd.setLocation(
LastExceptionSpecToken.getLocation().getLocWithOffset(
LastExceptionSpecToken.getLength()));
ExceptionSpecEnd.setEofData(LM.Method);
Toks->push_back(ExceptionSpecEnd);
// Parse the default argument from its saved token stream.
Toks->push_back(Tok); // So that the current token doesn't get lost
PP.EnterTokenStream(&Toks->front(), Toks->size(), true, false);
// Consume the previously-pushed token.
ConsumeAnyToken();
// C++11 [expr.prim.general]p3:
// If a declaration declares a member function or member function
// template of a class X, the expression this is a prvalue of type
// "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq
// and the end of the function-definition, member-declarator, or
// declarator.
CXXMethodDecl *Method;
if (FunctionTemplateDecl *FunTmpl
= dyn_cast<FunctionTemplateDecl>(LM.Method))
Method = cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl());
else
Method = cast<CXXMethodDecl>(LM.Method);
Sema::CXXThisScopeRAII ThisScope(Actions, Method->getParent(),
Method->getTypeQualifiers(),
getLangOpts().CPlusPlus11);
// Parse the exception-specification.
SourceRange SpecificationRange;
SmallVector<ParsedType, 4> DynamicExceptions;
SmallVector<SourceRange, 4> DynamicExceptionRanges;
ExprResult NoexceptExpr;
CachedTokens *ExceptionSpecTokens;
ExceptionSpecificationType EST
= tryParseExceptionSpecification(/*Delayed=*/false, SpecificationRange,
DynamicExceptions,
DynamicExceptionRanges, NoexceptExpr,
ExceptionSpecTokens);
if (Tok.isNot(tok::eof) || Tok.getEofData() != LM.Method)
Diag(Tok.getLocation(), diag::err_except_spec_unparsed);
// Attach the exception-specification to the method.
Actions.actOnDelayedExceptionSpecification(LM.Method, EST,
SpecificationRange,
DynamicExceptions,
DynamicExceptionRanges,
NoexceptExpr.isUsable()?
NoexceptExpr.get() : nullptr);
// There could be leftover tokens (e.g. because of an error).
// Skip through until we reach the original token position.
while (Tok.isNot(tok::eof))
ConsumeAnyToken();
// Clean up the remaining EOF token.
if (Tok.is(tok::eof) && Tok.getEofData() == LM.Method)
ConsumeAnyToken();
delete Toks;
LM.ExceptionSpecTokens = nullptr;
}
PrototypeScope.Exit();
// Finish the delayed C++ method declaration.
Actions.ActOnFinishDelayedCXXMethodDeclaration(getCurScope(), LM.Method);
}
