diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 016aafee016c2..91fc57dfac595 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -247,9 +247,6 @@ C++2b Feature Support - Implemented `P2128R6: Multidimensional subscript operator `_. - Implemented `P0849R8: auto(x): decay-copy in the language `_. - Implemented `P2242R3: Non-literal variables (and labels and gotos) in constexpr functions `_. -- Implemented `P2036R3: Change scope of lambda trailing-return-type `_. - This proposal modifies how variables captured in lambdas can appear in trailing return type - expressions and how their types are deduced therein, in all C++ language versions. CUDA Language Changes in Clang ------------------------------ diff --git a/clang/include/clang/AST/DeclCXX.h b/clang/include/clang/AST/DeclCXX.h index c640f7f7ba63f..04a9daa14e05e 100644 --- a/clang/include/clang/AST/DeclCXX.h +++ b/clang/include/clang/AST/DeclCXX.h @@ -1799,20 +1799,6 @@ class CXXRecordDecl : public RecordDecl { return getLambdaData().MethodTyInfo; } - void setLambdaTypeInfo(TypeSourceInfo *TS) { - auto *DD = DefinitionData; - assert(DD && DD->IsLambda && "setting lambda property of non-lambda class"); - auto &DL = static_cast(*DD); - DL.MethodTyInfo = TS; - } - - void setLambdaIsGeneric(bool IsGeneric) { - auto *DD = DefinitionData; - assert(DD && DD->IsLambda && "setting lambda property of non-lambda class"); - auto &DL = static_cast(*DD); - DL.IsGenericLambda = IsGeneric; - } - // Determine whether this type is an Interface Like type for // __interface inheritance purposes. bool isInterfaceLike() const; diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index e154925538f3a..3213163ee7876 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -7704,8 +7704,6 @@ let CategoryName = "Lambda Issue" in { def err_lambda_impcap : Error< "variable %0 cannot be implicitly captured in a lambda with no " "capture-default specified">; - def err_lambda_used_before_capture: Error< - "captured variable %0 cannot appear here">; def note_lambda_variable_capture_fixit : Note< "capture %0 by %select{value|reference}1">; def note_lambda_default_capture_fixit : Note< diff --git a/clang/include/clang/Sema/Scope.h b/clang/include/clang/Sema/Scope.h index 5a2d51b63d909..872951a0829b4 100644 --- a/clang/include/clang/Sema/Scope.h +++ b/clang/include/clang/Sema/Scope.h @@ -44,11 +44,11 @@ class Scope { enum ScopeFlags { /// This indicates that the scope corresponds to a function, which /// means that labels are set here. - FnScope = 0x01, + FnScope = 0x01, /// This is a while, do, switch, for, etc that can have break /// statements embedded into it. - BreakScope = 0x02, + BreakScope = 0x02, /// This is a while, do, for, which can have continue statements /// embedded into it. @@ -140,12 +140,6 @@ class Scope { /// parsed. If such a scope is a ContinueScope, it's invalid to jump to the /// continue block from here. ConditionVarScope = 0x2000000, - - /// This is the scope for a lambda, after the lambda introducer. - /// Lambdas need 2 FunctionPrototypeScope scopes (because there is a - /// template scope in between), the outer scope does not increase the - /// depth of recursion. - LambdaScope = 0x4000000, }; private: diff --git a/clang/include/clang/Sema/ScopeInfo.h b/clang/include/clang/Sema/ScopeInfo.h index 11a9fdc513da9..08bf53d22f8a4 100644 --- a/clang/include/clang/Sema/ScopeInfo.h +++ b/clang/include/clang/Sema/ScopeInfo.h @@ -831,28 +831,6 @@ class LambdaScopeInfo final : /// The lambda's compiler-generated \c operator(). CXXMethodDecl *CallOperator = nullptr; - struct DelayedCapture { - VarDecl *Var; - SourceLocation Loc; - LambdaCaptureKind Kind; - }; - - /// Holds the captures until we parsed the qualifiers, as the cv qualified - /// type of captures can only be computed at that point, and the captures - /// should not be visible before. - /// The index represents the position in the original capture list. - /// We use a map as not all index represents captures (defaults), or are - /// captured (some captures are invalid). - llvm::DenseMap DelayedCaptures; - - /// Whether the current scope when parsing the lambda - /// is after the call operator qualifiers, - /// which is the point at which the captures are usable - /// per [expr.prim.id.unqual]/p3.2 and [expr.prim.lambda.capture]/6. - /// This is set to false by default as the lambda can be reconstructed during - /// instantiation - bool BeforeLambdaQualifiersScope = false; - /// Source range covering the lambda introducer [...]. SourceRange IntroducerRange; diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h index 5c6c0e90588e6..fae0ca1fa1e09 100644 --- a/clang/include/clang/Sema/Sema.h +++ b/clang/include/clang/Sema/Sema.h @@ -6852,9 +6852,11 @@ class Sema final { /// /// CodeGen handles emission of lambda captures, ignoring these dummy /// variables appropriately. - VarDecl *createLambdaInitCaptureVarDecl( - SourceLocation Loc, QualType InitCaptureType, SourceLocation EllipsisLoc, - IdentifierInfo *Id, unsigned InitStyle, Expr *Init, DeclContext *DeclCtx); + VarDecl *createLambdaInitCaptureVarDecl(SourceLocation Loc, + QualType InitCaptureType, + SourceLocation EllipsisLoc, + IdentifierInfo *Id, + unsigned InitStyle, Expr *Init); /// Add an init-capture to a lambda scope. void addInitCapture(sema::LambdaScopeInfo *LSI, VarDecl *Var); @@ -6863,28 +6865,21 @@ class Sema final { /// given lambda. void finishLambdaExplicitCaptures(sema::LambdaScopeInfo *LSI); - /// Deduce a block or lambda's return type based on the return - /// statements present in the body. - void deduceClosureReturnType(sema::CapturingScopeInfo &CSI); - - /// Once the Lambdas capture are known, we can - /// start to create the closure, call operator method, - /// and keep track of the captures. - /// We do the capture lookup here, but they are not actually captured - /// until after we know what the qualifiers of the call operator are. - void ActOnLambdaIntroducer(LambdaIntroducer &Intro, Scope *CurContext); - - /// This is called after parsing the explicit template parameter list + /// \brief This is called after parsing the explicit template parameter list /// on a lambda (if it exists) in C++2a. - void ActOnLambdaExplicitTemplateParameterList(LambdaIntroducer &Intro, - SourceLocation LAngleLoc, + void ActOnLambdaExplicitTemplateParameterList(SourceLocation LAngleLoc, ArrayRef TParams, SourceLocation RAngleLoc, ExprResult RequiresClause); - void ActOnLambdaClosureQualifiers(LambdaIntroducer &Intro, - SourceLocation MutableLoc, - SourceLocation EndLoc, const DeclSpec &DS); + /// Introduce the lambda parameters into scope. + void addLambdaParameters( + ArrayRef Captures, + CXXMethodDecl *CallOperator, Scope *CurScope); + + /// Deduce a block or lambda's return type based on the return + /// statements present in the body. + void deduceClosureReturnType(sema::CapturingScopeInfo &CSI); /// ActOnStartOfLambdaDefinition - This is called just before we start /// parsing the body of a lambda; it analyzes the explicit captures and diff --git a/clang/lib/Parse/ParseExprCXX.cpp b/clang/lib/Parse/ParseExprCXX.cpp index 678785f2e9fc0..7b66f6c46339a 100644 --- a/clang/lib/Parse/ParseExprCXX.cpp +++ b/clang/lib/Parse/ParseExprCXX.cpp @@ -1250,13 +1250,7 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer( DeclSpec DS(AttrFactory); Declarator D(DS, DeclaratorContext::LambdaExpr); TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth); - - ParseScope LambdaScope(this, Scope::LambdaScope | Scope::DeclScope | - Scope::FunctionDeclarationScope | - Scope::FunctionPrototypeScope); - Actions.PushLambdaScope(); - Actions.ActOnLambdaIntroducer(Intro, getCurScope()); ParsedAttributes Attr(AttrFactory); if (getLangOpts().CUDA) { @@ -1306,7 +1300,7 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer( } Actions.ActOnLambdaExplicitTemplateParameterList( - Intro, LAngleLoc, TemplateParams, RAngleLoc, RequiresClause); + LAngleLoc, TemplateParams, RAngleLoc, RequiresClause); ++CurTemplateDepthTracker; } } @@ -1324,31 +1318,28 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer( TypeResult TrailingReturnType; SourceLocation TrailingReturnTypeLoc; - SourceLocation LParenLoc, RParenLoc; - SourceLocation DeclEndLoc; - bool HasParentheses = false; - bool HasSpecifiers = false; - SourceLocation MutableLoc; - - auto ParseConstexprAndMutableSpecifiers = [&] { - // GNU-style attributes must be parsed before the mutable specifier to - // be compatible with GCC. MSVC-style attributes must be parsed before - // the mutable specifier to be compatible with MSVC. - MaybeParseAttributes(PAKM_GNU | PAKM_Declspec, Attr); - // Parse mutable-opt and/or constexpr-opt or consteval-opt, and update - // the DeclEndLoc. - SourceLocation ConstexprLoc; - SourceLocation ConstevalLoc; - tryConsumeLambdaSpecifierToken(*this, MutableLoc, ConstexprLoc, - ConstevalLoc, DeclEndLoc); - - addConstexprToLambdaDeclSpecifier(*this, ConstexprLoc, DS); - addConstevalToLambdaDeclSpecifier(*this, ConstevalLoc, DS); - }; auto ParseLambdaSpecifiers = - [&](MutableArrayRef ParamInfo, + [&](SourceLocation LParenLoc, SourceLocation RParenLoc, + MutableArrayRef ParamInfo, SourceLocation EllipsisLoc) { + SourceLocation DeclEndLoc = RParenLoc; + + // GNU-style attributes must be parsed before the mutable specifier to + // be compatible with GCC. MSVC-style attributes must be parsed before + // the mutable specifier to be compatible with MSVC. + MaybeParseAttributes(PAKM_GNU | PAKM_Declspec, Attr); + + // Parse mutable-opt and/or constexpr-opt or consteval-opt, and update + // the DeclEndLoc. + SourceLocation MutableLoc; + SourceLocation ConstexprLoc; + SourceLocation ConstevalLoc; + tryConsumeLambdaSpecifierToken(*this, MutableLoc, ConstexprLoc, + ConstevalLoc, DeclEndLoc); + + addConstexprToLambdaDeclSpecifier(*this, ConstexprLoc, DS); + addConstevalToLambdaDeclSpecifier(*this, ConstevalLoc, DS); // Parse exception-specification[opt]. ExceptionSpecificationType ESpecType = EST_None; SourceRange ESpecRange; @@ -1402,22 +1393,20 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer( /*DeclsInPrototype=*/None, LParenLoc, FunLocalRangeEnd, D, TrailingReturnType, TrailingReturnTypeLoc, &DS), std::move(Attr), DeclEndLoc); - - if (HasParentheses && Tok.is(tok::kw_requires)) - ParseTrailingRequiresClause(D); }; - ParseScope Prototype(this, Scope::FunctionPrototypeScope | - Scope::FunctionDeclarationScope | - Scope::DeclScope); - - // Parse parameter-declaration-clause. - SmallVector ParamInfo; - SourceLocation EllipsisLoc; if (Tok.is(tok::l_paren)) { + ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope | + Scope::FunctionDeclarationScope | + Scope::DeclScope); + BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); - LParenLoc = T.getOpenLocation(); + SourceLocation LParenLoc = T.getOpenLocation(); + + // Parse parameter-declaration-clause. + SmallVector ParamInfo; + SourceLocation EllipsisLoc; if (Tok.isNot(tok::r_paren)) { Actions.RecordParsingTemplateParameterDepth( @@ -1435,38 +1424,36 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer( } T.consumeClose(); - DeclEndLoc = RParenLoc = T.getCloseLocation(); - HasParentheses = true; - } - if (Tok.isOneOf(tok::kw_mutable, tok::arrow, tok::kw___attribute, - tok::kw_constexpr, tok::kw_consteval, tok::kw___private, - tok::kw___global, tok::kw___local, tok::kw___constant, - tok::kw___generic, tok::kw_requires, tok::kw_noexcept) || - (Tok.is(tok::l_square) && NextToken().is(tok::l_square))) { - HasSpecifiers = true; - if (!HasParentheses && !getLangOpts().CPlusPlus2b) { + // Parse lambda-specifiers. + ParseLambdaSpecifiers(LParenLoc, /*DeclEndLoc=*/T.getCloseLocation(), + ParamInfo, EllipsisLoc); + + // Parse requires-clause[opt]. + if (Tok.is(tok::kw_requires)) + ParseTrailingRequiresClause(D); + } else if (Tok.isOneOf(tok::kw_mutable, tok::arrow, tok::kw___attribute, + tok::kw_constexpr, tok::kw_consteval, + tok::kw___private, tok::kw___global, tok::kw___local, + tok::kw___constant, tok::kw___generic, + tok::kw_requires, tok::kw_noexcept) || + (Tok.is(tok::l_square) && NextToken().is(tok::l_square))) { + if (!getLangOpts().CPlusPlus2b) // It's common to forget that one needs '()' before 'mutable', an // attribute specifier, the result type, or the requires clause. Deal with // this. Diag(Tok, diag::ext_lambda_missing_parens) << FixItHint::CreateInsertion(Tok.getLocation(), "() "); - } - } - if (HasParentheses || HasSpecifiers) { - ParseConstexprAndMutableSpecifiers(); + SourceLocation NoLoc; + // Parse lambda-specifiers. + std::vector EmptyParamInfo; + ParseLambdaSpecifiers(/*LParenLoc=*/NoLoc, /*RParenLoc=*/NoLoc, + EmptyParamInfo, /*EllipsisLoc=*/NoLoc); } - Actions.ActOnLambdaClosureQualifiers(Intro, MutableLoc, DeclEndLoc, DS); - - if (HasSpecifiers || HasParentheses) - ParseLambdaSpecifiers(ParamInfo, EllipsisLoc); - WarnIfHasCUDATargetAttr(); - Prototype.Exit(); - // FIXME: Rename BlockScope -> ClosureScope if we decide to continue using // it. unsigned ScopeFlags = Scope::BlockScope | Scope::FnScope | Scope::DeclScope | @@ -1485,7 +1472,6 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer( StmtResult Stmt(ParseCompoundStatementBody()); BodyScope.Exit(); TemplateParamScope.Exit(); - LambdaScope.Exit(); if (!Stmt.isInvalid() && !TrailingReturnType.isInvalid()) return Actions.ActOnLambdaExpr(LambdaBeginLoc, Stmt.get(), getCurScope()); diff --git a/clang/lib/Sema/Scope.cpp b/clang/lib/Sema/Scope.cpp index 00519c132a6a4..499279a2659dd 100644 --- a/clang/lib/Sema/Scope.cpp +++ b/clang/lib/Sema/Scope.cpp @@ -67,10 +67,8 @@ void Scope::setFlags(Scope *parent, unsigned flags) { if (flags & BlockScope) BlockParent = this; if (flags & TemplateParamScope) TemplateParamParent = this; - // If this is a prototype scope, record that. Lambdas have an extra prototype - // scope that doesn't add any depth. - if (flags & FunctionPrototypeScope && !(flags & LambdaScope)) - PrototypeDepth++; + // If this is a prototype scope, record that. + if (flags & FunctionPrototypeScope) PrototypeDepth++; if (flags & DeclScope) { if (flags & FunctionPrototypeScope) diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp index 4f86a06e820ae..ce104f377730c 100644 --- a/clang/lib/Sema/Sema.cpp +++ b/clang/lib/Sema/Sema.cpp @@ -2297,8 +2297,7 @@ FunctionScopeInfo *Sema::getEnclosingFunction() const { LambdaScopeInfo *Sema::getEnclosingLambda() const { for (auto *Scope : llvm::reverse(FunctionScopes)) { if (auto *LSI = dyn_cast(Scope)) { - if (LSI->Lambda && !LSI->Lambda->Encloses(CurContext) && - !LSI->BeforeLambdaQualifiersScope) { + if (LSI->Lambda && !LSI->Lambda->Encloses(CurContext)) { // We have switched contexts due to template instantiation. // FIXME: We should swap out the FunctionScopes during code synthesis // so that we don't need to check for this. @@ -2324,9 +2323,8 @@ LambdaScopeInfo *Sema::getCurLambda(bool IgnoreNonLambdaCapturingScope) { return nullptr; } auto *CurLSI = dyn_cast(*I); - if (CurLSI && CurLSI->Lambda && CurLSI->CallOperator && - !CurLSI->Lambda->Encloses(CurContext) && - !CurLSI->BeforeLambdaQualifiersScope) { + if (CurLSI && CurLSI->Lambda && + !CurLSI->Lambda->Encloses(CurContext)) { // We have switched contexts due to template instantiation. assert(!CodeSynthesisContexts.empty()); return nullptr; diff --git a/clang/lib/Sema/SemaCXXScopeSpec.cpp b/clang/lib/Sema/SemaCXXScopeSpec.cpp index f7e8ebd6e203f..4781d71080c98 100644 --- a/clang/lib/Sema/SemaCXXScopeSpec.cpp +++ b/clang/lib/Sema/SemaCXXScopeSpec.cpp @@ -292,11 +292,6 @@ bool Sema::ActOnCXXGlobalScopeSpecifier(SourceLocation CCLoc, bool Sema::ActOnSuperScopeSpecifier(SourceLocation SuperLoc, SourceLocation ColonColonLoc, CXXScopeSpec &SS) { - if (getCurLambda()) { - Diag(SuperLoc, diag::err_super_in_lambda_unsupported); - return true; - } - CXXRecordDecl *RD = nullptr; for (Scope *S = getCurScope(); S; S = S->getParent()) { if (S->isFunctionScope()) { @@ -313,6 +308,9 @@ bool Sema::ActOnSuperScopeSpecifier(SourceLocation SuperLoc, if (!RD) { Diag(SuperLoc, diag::err_invalid_super_scope); return true; + } else if (RD->isLambda()) { + Diag(SuperLoc, diag::err_super_in_lambda_unsupported); + return true; } else if (RD->getNumBases() == 0) { Diag(SuperLoc, diag::err_no_base_classes) << RD->getName(); return true; diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index ae3aaa65d4ac5..da1fed4d72aec 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -3383,7 +3383,7 @@ ExprResult Sema::BuildDeclarationNameExpr( // FIXME: Support lambda-capture of BindingDecls, once CWG actually // decides how that's supposed to work. auto *BD = cast(VD); - if (BD->getDeclContext() != CurContext && !isUnevaluatedContext()) { + if (BD->getDeclContext() != CurContext) { auto *DD = dyn_cast_or_null(BD->getDecomposedDecl()); if (DD && DD->hasLocalStorage()) diagnoseUncapturableValueReference(*this, Loc, BD); @@ -18398,37 +18398,6 @@ static void buildLambdaCaptureFixit(Sema &Sema, LambdaScopeInfo *LSI, } } -static bool CheckCaptureUseBeforeLambdaQualifiers(Sema &S, VarDecl *Var, - SourceLocation ExprLoc, - LambdaScopeInfo *LSI) { - if (Var->isInvalidDecl()) - return false; - - bool ByCopy = LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByval; - SourceLocation Loc = LSI->IntroducerRange.getBegin(); - bool Explicitly = false; - for (auto &&C : LSI->DelayedCaptures) { - VarDecl *CV = C.second.Var; - if (Var != CV) - continue; - ByCopy = C.second.Kind == LambdaCaptureKind::LCK_ByCopy; - Loc = C.second.Loc; - Explicitly = true; - break; - } - if (ByCopy && LSI->BeforeLambdaQualifiersScope) { - // This can only occur in a non-ODR context, so we need to diagnose eagerly, - // even when BuildAndDiagnose is false - S.Diag(ExprLoc, diag::err_lambda_used_before_capture) << Var; - S.Diag(Loc, diag::note_var_explicitly_captured_here) << Var << Explicitly; - if (!Var->isInitCapture()) - S.Diag(Var->getBeginLoc(), diag::note_entity_declared_at) << Var; - Var->setInvalidDecl(); - return false; - } - return true; -} - bool Sema::tryCaptureVariable( VarDecl *Var, SourceLocation ExprLoc, TryCaptureKind Kind, SourceLocation EllipsisLoc, bool BuildAndDiagnose, QualType &CaptureType, @@ -18452,6 +18421,11 @@ bool Sema::tryCaptureVariable( } } + + // If the variable is declared in the current context, there is no need to + // capture it. + if (VarDC == DC) return true; + // Capture global variables if it is required to use private copy of this // variable. bool IsGlobal = !Var->hasLocalStorage(); @@ -18474,36 +18448,13 @@ bool Sema::tryCaptureVariable( bool Nested = false; bool Explicit = (Kind != TryCapture_Implicit); unsigned FunctionScopesIndex = MaxFunctionScopesIndex; - bool IsInLambdaBeforeQualifiers; do { - IsInLambdaBeforeQualifiers = false; - - LambdaScopeInfo *LSI = nullptr; - if (!FunctionScopes.empty()) - LSI = dyn_cast_or_null( - FunctionScopes[FunctionScopesIndex]); - if (LSI && LSI->BeforeLambdaQualifiersScope) { - if (isa(Var)) - return true; - IsInLambdaBeforeQualifiers = true; - if (!CheckCaptureUseBeforeLambdaQualifiers(*this, Var, ExprLoc, LSI)) { - break; - } - } - - // If the variable is declared in the current context, there is no need to - // capture it. - if (!IsInLambdaBeforeQualifiers && - FunctionScopesIndex == MaxFunctionScopesIndex && VarDC == DC) - return true; - // Only block literals, captured statements, and lambda expressions can // capture; other scopes don't work. - DeclContext *ParentDC = - IsInLambdaBeforeQualifiers - ? DC->getParent() - : getParentOfCapturingContextOrNull(DC, Var, ExprLoc, - BuildAndDiagnose, *this); + DeclContext *ParentDC = getParentOfCapturingContextOrNull(DC, Var, + ExprLoc, + BuildAndDiagnose, + *this); // We need to check for the parent *first* because, if we *have* // private-captured a global variable, we need to recursively capture it in // intermediate blocks, lambdas, etc. @@ -18518,9 +18469,9 @@ bool Sema::tryCaptureVariable( FunctionScopeInfo *FSI = FunctionScopes[FunctionScopesIndex]; CapturingScopeInfo *CSI = cast(FSI); + // Check whether we've already captured it. - if (!IsInLambdaBeforeQualifiers && - isVariableAlreadyCapturedInScopeInfo(CSI, Var, Nested, CaptureType, + if (isVariableAlreadyCapturedInScopeInfo(CSI, Var, Nested, CaptureType, DeclRefType)) { CSI->getCapture(Var).markUsed(BuildAndDiagnose); break; @@ -18529,8 +18480,7 @@ bool Sema::tryCaptureVariable( // we do not want to capture new variables. What was captured // during either a lambdas transformation or initial parsing // should be used. - if (!IsInLambdaBeforeQualifiers && - isGenericLambdaCallOperatorSpecialization(DC)) { + if (isGenericLambdaCallOperatorSpecialization(DC)) { if (BuildAndDiagnose) { LambdaScopeInfo *LSI = cast(CSI); if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None) { @@ -18545,8 +18495,7 @@ bool Sema::tryCaptureVariable( } // Try to capture variable-length arrays types. - if (!IsInLambdaBeforeQualifiers && - Var->getType()->isVariablyModifiedType()) { + if (Var->getType()->isVariablyModifiedType()) { // We're going to walk down into the type and look for VLA // expressions. QualType QTy = Var->getType(); @@ -18555,7 +18504,7 @@ bool Sema::tryCaptureVariable( captureVariablyModifiedType(Context, QTy, CSI); } - if (!IsInLambdaBeforeQualifiers && getLangOpts().OpenMP) { + if (getLangOpts().OpenMP) { if (auto *RSI = dyn_cast(CSI)) { // OpenMP private variables should not be captured in outer scope, so // just break here. Similarly, global variables that are captured in a @@ -18636,11 +18585,11 @@ bool Sema::tryCaptureVariable( } return true; } - Explicit = false; + FunctionScopesIndex--; - if (!IsInLambdaBeforeQualifiers) - DC = ParentDC; - } while (IsInLambdaBeforeQualifiers || !VarDC->Equals(DC)); + DC = ParentDC; + Explicit = false; + } while (!VarDC->Equals(DC)); // Walk back down the scope stack, (e.g. from outer lambda to inner lambda) // computing the type of the capture at each step, checking type-specific @@ -18675,9 +18624,6 @@ bool Sema::tryCaptureVariable( Nested = true; } else { LambdaScopeInfo *LSI = cast(CSI); - if (!CheckCaptureUseBeforeLambdaQualifiers(*this, Var, ExprLoc, LSI)) { - return true; - } Invalid = !captureInLambda(LSI, Var, ExprLoc, BuildAndDiagnose, CaptureType, DeclRefType, Nested, Kind, EllipsisLoc, diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp index aad9574e9e694..f360dc6e1a236 100644 --- a/clang/lib/Sema/SemaExprCXX.cpp +++ b/clang/lib/Sema/SemaExprCXX.cpp @@ -1130,7 +1130,7 @@ static QualType adjustCVQualifiersForCXXThisWithinLambda( if (C.isCopyCapture()) { ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask); - if (!CurLSI->Mutable) + if (CurLSI->CallOperator->isConst()) ClassType.addConst(); return ASTCtx.getPointerType(ClassType); } diff --git a/clang/lib/Sema/SemaLambda.cpp b/clang/lib/Sema/SemaLambda.cpp index a4e131d4adccf..c0b2fad530c5c 100644 --- a/clang/lib/Sema/SemaLambda.cpp +++ b/clang/lib/Sema/SemaLambda.cpp @@ -245,9 +245,8 @@ Sema::createLambdaClosureType(SourceRange IntroducerRange, TypeSourceInfo *Info, DeclContext *DC = CurContext; while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext())) DC = DC->getParent(); - - bool IsGenericLambda = - Info && getGenericLambdaTemplateParameterList(getCurLambda(), *this); + bool IsGenericLambda = getGenericLambdaTemplateParameterList(getCurLambda(), + *this); // Start constructing the lambda class. CXXRecordDecl *Class = CXXRecordDecl::CreateLambda( Context, DC, Info, IntroducerRange.getBegin(), LambdaDependencyKind, @@ -355,13 +354,16 @@ Sema::getCurrentMangleNumberContext(const DeclContext *DC) { llvm_unreachable("unexpected context"); } -static QualType -buildTypeForLambdaCallOperator(Sema &S, clang::CXXRecordDecl *Class, - TemplateParameterList *TemplateParams, - TypeSourceInfo *MethodTypeInfo) { - assert(MethodTypeInfo && "expected a non null type"); - +CXXMethodDecl *Sema::startLambdaDefinition(CXXRecordDecl *Class, + SourceRange IntroducerRange, + TypeSourceInfo *MethodTypeInfo, + SourceLocation EndLoc, + ArrayRef Params, + ConstexprSpecKind ConstexprKind, + Expr *TrailingRequiresClause) { QualType MethodType = MethodTypeInfo->getType(); + TemplateParameterList *TemplateParams = + getGenericLambdaTemplateParameterList(getCurLambda(), *this); // If a lambda appears in a dependent context or is a generic lambda (has // template parameters) and has an 'auto' return type, deduce it to a // dependent type. @@ -369,43 +371,19 @@ buildTypeForLambdaCallOperator(Sema &S, clang::CXXRecordDecl *Class, const FunctionProtoType *FPT = MethodType->castAs(); QualType Result = FPT->getReturnType(); if (Result->isUndeducedType()) { - Result = S.SubstAutoTypeDependent(Result); - MethodType = S.Context.getFunctionType(Result, FPT->getParamTypes(), - FPT->getExtProtoInfo()); + Result = SubstAutoTypeDependent(Result); + MethodType = Context.getFunctionType(Result, FPT->getParamTypes(), + FPT->getExtProtoInfo()); } } - return MethodType; -} - -/// Start the definition of a lambda expression. -/// In this overload, we do not know the type yet -CXXMethodDecl *Sema::startLambdaDefinition(CXXRecordDecl *Class, - SourceRange IntroducerRange, - TypeSourceInfo *MethodTypeInfo, - SourceLocation EndLoc, - ArrayRef Params, - ConstexprSpecKind ConstexprKind, - Expr *TrailingRequiresClause) { - - LambdaScopeInfo *LSI = getCurLambda(); - - TemplateParameterList *TemplateParams = - getGenericLambdaTemplateParameterList(LSI, *this); - - // At this point, we may not know the type of the lambda, if we have not - // parsed a trailing return type yet - QualType MethodType = MethodTypeInfo - ? buildTypeForLambdaCallOperator( - *this, Class, TemplateParams, MethodTypeInfo) - : QualType(); // C++11 [expr.prim.lambda]p5: // The closure type for a lambda-expression has a public inline function - // call operator (13.5.4) whose parameters and return type are described - // by the lambda-expression's parameter-declaration-clause and + // call operator (13.5.4) whose parameters and return type are described by + // the lambda-expression's parameter-declaration-clause and // trailing-return-type respectively. - DeclarationName MethodName = - Context.DeclarationNames.getCXXOperatorName(OO_Call); + DeclarationName MethodName + = Context.DeclarationNames.getCXXOperatorName(OO_Call); DeclarationNameLoc MethodNameLoc = DeclarationNameLoc::makeCXXOperatorNameLoc(IntroducerRange); CXXMethodDecl *Method = CXXMethodDecl::Create( @@ -422,11 +400,11 @@ CXXMethodDecl *Sema::startLambdaDefinition(CXXRecordDecl *Class, // context, so that the Scope stack matches the lexical nesting. Method->setLexicalDeclContext(CurContext); // Create a function template if we have a template parameter list - FunctionTemplateDecl *const TemplateMethod = - TemplateParams - ? FunctionTemplateDecl::Create(Context, Class, Method->getLocation(), - MethodName, TemplateParams, Method) - : nullptr; + FunctionTemplateDecl *const TemplateMethod = TemplateParams ? + FunctionTemplateDecl::Create(Context, Class, + Method->getLocation(), MethodName, + TemplateParams, + Method) : nullptr; if (TemplateMethod) { TemplateMethod->setAccess(AS_public); Method->setDescribedFunctionTemplate(TemplateMethod); @@ -502,27 +480,14 @@ void Sema::handleLambdaNumbering( } } -static void buildLambdaScopeReturnType(Sema &S, LambdaScopeInfo *LSI, - CXXMethodDecl *CallOperator, - bool ExplicitResultType) { - if (ExplicitResultType) { - LSI->HasImplicitReturnType = false; - LSI->ReturnType = CallOperator->getReturnType(); - if (!LSI->ReturnType->isDependentType() && !LSI->ReturnType->isVoidType()) { - S.RequireCompleteType(CallOperator->getBeginLoc(), LSI->ReturnType, - diag::err_lambda_incomplete_result); - } - } else { - LSI->HasImplicitReturnType = true; - } -} - -static void buildLambdaScopeCaptures(LambdaScopeInfo *LSI, - CXXMethodDecl *CallOperator, - SourceRange IntroducerRange, - LambdaCaptureDefault CaptureDefault, - SourceLocation CaptureDefaultLoc, - bool ExplicitParams, bool Mutable) { +void Sema::buildLambdaScope(LambdaScopeInfo *LSI, + CXXMethodDecl *CallOperator, + SourceRange IntroducerRange, + LambdaCaptureDefault CaptureDefault, + SourceLocation CaptureDefaultLoc, + bool ExplicitParams, + bool ExplicitResultType, + bool Mutable) { LSI->CallOperator = CallOperator; CXXRecordDecl *LambdaClass = CallOperator->getParent(); LSI->Lambda = LambdaClass; @@ -534,27 +499,30 @@ static void buildLambdaScopeCaptures(LambdaScopeInfo *LSI, LSI->IntroducerRange = IntroducerRange; LSI->ExplicitParams = ExplicitParams; LSI->Mutable = Mutable; -} -void Sema::buildLambdaScope(LambdaScopeInfo *LSI, CXXMethodDecl *CallOperator, - SourceRange IntroducerRange, - LambdaCaptureDefault CaptureDefault, - SourceLocation CaptureDefaultLoc, - bool ExplicitParams, bool ExplicitResultType, - bool Mutable) { - buildLambdaScopeCaptures(LSI, CallOperator, IntroducerRange, CaptureDefault, - CaptureDefaultLoc, ExplicitParams, Mutable); - buildLambdaScopeReturnType(*this, LSI, CallOperator, ExplicitResultType); + if (ExplicitResultType) { + LSI->ReturnType = CallOperator->getReturnType(); + + if (!LSI->ReturnType->isDependentType() && + !LSI->ReturnType->isVoidType()) { + if (RequireCompleteType(CallOperator->getBeginLoc(), LSI->ReturnType, + diag::err_lambda_incomplete_result)) { + // Do nothing. + } + } + } else { + LSI->HasImplicitReturnType = true; + } } void Sema::finishLambdaExplicitCaptures(LambdaScopeInfo *LSI) { LSI->finishedExplicitCaptures(); } -void Sema::ActOnLambdaExplicitTemplateParameterList( - LambdaIntroducer &Intro, SourceLocation LAngleLoc, - ArrayRef TParams, SourceLocation RAngleLoc, - ExprResult RequiresClause) { +void Sema::ActOnLambdaExplicitTemplateParameterList(SourceLocation LAngleLoc, + ArrayRef TParams, + SourceLocation RAngleLoc, + ExprResult RequiresClause) { LambdaScopeInfo *LSI = getCurLambda(); assert(LSI && "Expected a lambda scope"); assert(LSI->NumExplicitTemplateParams == 0 && @@ -570,6 +538,35 @@ void Sema::ActOnLambdaExplicitTemplateParameterList( LSI->RequiresClause = RequiresClause; } +void Sema::addLambdaParameters( + ArrayRef Captures, + CXXMethodDecl *CallOperator, Scope *CurScope) { + // Introduce our parameters into the function scope + for (unsigned p = 0, NumParams = CallOperator->getNumParams(); + p < NumParams; ++p) { + ParmVarDecl *Param = CallOperator->getParamDecl(p); + + // If this has an identifier, add it to the scope stack. + if (CurScope && Param->getIdentifier()) { + bool Error = false; + // Resolution of CWG 2211 in C++17 renders shadowing ill-formed, but we + // retroactively apply it. + for (const auto &Capture : Captures) { + if (Capture.Id == Param->getIdentifier()) { + Error = true; + Diag(Param->getLocation(), diag::err_parameter_shadow_capture); + Diag(Capture.Loc, diag::note_var_explicitly_captured_here) + << Capture.Id << true; + } + } + if (!Error) + CheckShadow(CurScope, Param); + + PushOnScopeChains(Param, CurScope); + } + } +} + /// If this expression is an enumerator-like expression of some type /// T, return the type T; otherwise, return null. /// @@ -856,9 +853,11 @@ QualType Sema::buildLambdaInitCaptureInitialization( return DeducedType; } -VarDecl *Sema::createLambdaInitCaptureVarDecl( - SourceLocation Loc, QualType InitCaptureType, SourceLocation EllipsisLoc, - IdentifierInfo *Id, unsigned InitStyle, Expr *Init, DeclContext *DeclCtx) { +VarDecl *Sema::createLambdaInitCaptureVarDecl(SourceLocation Loc, + QualType InitCaptureType, + SourceLocation EllipsisLoc, + IdentifierInfo *Id, + unsigned InitStyle, Expr *Init) { // FIXME: Retain the TypeSourceInfo from buildLambdaInitCaptureInitialization // rather than reconstructing it here. TypeSourceInfo *TSI = Context.getTrivialTypeSourceInfo(InitCaptureType, Loc); @@ -869,8 +868,8 @@ VarDecl *Sema::createLambdaInitCaptureVarDecl( // used as a variable, and only exists as a way to name and refer to the // init-capture. // FIXME: Pass in separate source locations for '&' and identifier. - VarDecl *NewVD = VarDecl::Create(Context, DeclCtx, Loc, Loc, Id, - InitCaptureType, TSI, SC_Auto); + VarDecl *NewVD = VarDecl::Create(Context, CurContext, Loc, + Loc, Id, InitCaptureType, TSI, SC_Auto); NewVD->setInitCapture(true); NewVD->setReferenced(true); // FIXME: Pass in a VarDecl::InitializationStyle. @@ -889,107 +888,12 @@ void Sema::addInitCapture(LambdaScopeInfo *LSI, VarDecl *Var) { Var->getType(), /*Invalid*/false); } -// Unlike getCurLambda, getCurrentLambdaScopeUnsafe doesn't -// check that the current lambda is in a consistent or fully constructed state. -static LambdaScopeInfo *getCurrentLambdaScopeUnsafe(Sema &S) { - assert(!S.FunctionScopes.empty()); - return cast(S.FunctionScopes[S.FunctionScopes.size() - 1]); -} - -static TypeSourceInfo * -getDummyLambdaType(Sema &S, SourceLocation Loc = SourceLocation()) { - // 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(S.Context.getDefaultCallingConvention( - /*IsVariadic=*/false, /*IsCXXMethod=*/true)); - EPI.HasTrailingReturn = true; - EPI.TypeQuals.addConst(); - LangAS AS = S.getDefaultCXXMethodAddrSpace(); - if (AS != LangAS::Default) - EPI.TypeQuals.addAddressSpace(AS); - - // C++1y [expr.prim.lambda]: - // The lambda return type is 'auto', which is replaced by the - // trailing-return type if provided and/or deduced from 'return' - // statements - // We don't do this before C++1y, because we don't support deduced return - // types there. - QualType DefaultTypeForNoTrailingReturn = S.getLangOpts().CPlusPlus14 - ? S.Context.getAutoDeductType() - : S.Context.DependentTy; - QualType MethodTy = - S.Context.getFunctionType(DefaultTypeForNoTrailingReturn, None, EPI); - return S.Context.getTrivialTypeSourceInfo(MethodTy, Loc); -} - -static TypeSourceInfo *getLambdaType(Sema &S, LambdaIntroducer &Intro, - Declarator &ParamInfo, Scope *CurScope, - SourceLocation Loc, - bool &ExplicitResultType) { - - ExplicitResultType = false; - - TypeSourceInfo *MethodTyInfo; - - if (ParamInfo.getNumTypeObjects() == 0) { - MethodTyInfo = getDummyLambdaType(S, Loc); - } else { - DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getFunctionTypeInfo(); - ExplicitResultType = FTI.hasTrailingReturnType(); - if (!FTI.hasMutableQualifier()) { - FTI.getOrCreateMethodQualifiers().SetTypeQual(DeclSpec::TQ_const, Loc); - } - - MethodTyInfo = S.GetTypeForDeclarator(ParamInfo, CurScope); - - assert(MethodTyInfo && "no type from lambda-declarator"); - - // Check for unexpanded parameter packs in the method type. - if (MethodTyInfo->getType()->containsUnexpandedParameterPack()) - S.DiagnoseUnexpandedParameterPack(Intro.Range.getBegin(), MethodTyInfo, - S.UPPC_DeclarationType); - } - return MethodTyInfo; -} - -static CXXMethodDecl *CreateMethod(Sema &S, SourceRange IntroducerRange, - CXXRecordDecl *Class) { - // C++11 [expr.prim.lambda]p5: - // The closure type for a lambda-expression has a public inline function - // call operator (13.5.4) whose parameters and return type are described - // by the lambda-expression's parameter-declaration-clause and - // trailing-return-type respectively. - DeclarationName MethodName = - S.Context.DeclarationNames.getCXXOperatorName(OO_Call); - DeclarationNameLoc MethodNameLoc = - DeclarationNameLoc::makeCXXOperatorNameLoc(IntroducerRange.getBegin()); - CXXMethodDecl *Method = CXXMethodDecl::Create( - S.Context, Class, SourceLocation(), - DeclarationNameInfo(MethodName, IntroducerRange.getBegin(), - MethodNameLoc), - QualType(), nullptr, SC_None, S.getCurFPFeatures().isFPConstrained(), - /*isInline=*/true, ConstexprSpecKind::Unspecified, SourceLocation(), - nullptr); - Method->setAccess(AS_public); - return Method; -} - -void Sema::ActOnLambdaIntroducer(LambdaIntroducer &Intro, Scope *CurrentScope) { - +void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro, + Declarator &ParamInfo, + Scope *CurScope) { LambdaScopeInfo *const LSI = getCurLambda(); assert(LSI && "LambdaScopeInfo should be on stack!"); - if (Intro.Default == LCD_ByCopy) - LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByval; - else if (Intro.Default == LCD_ByRef) - LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByref; - LSI->CaptureDefaultLoc = Intro.DefaultLoc; - LSI->IntroducerRange = Intro.Range; - LSI->BeforeLambdaQualifiersScope = true; - - assert(LSI->NumExplicitTemplateParams == 0); - // Determine if we're within a context where we know that the lambda will // be dependent, because there are template parameters in scope. CXXRecordDecl::LambdaDependencyKind LambdaDependencyKind = @@ -1006,37 +910,181 @@ void Sema::ActOnLambdaIntroducer(LambdaIntroducer &Intro, Scope *CurrentScope) { LambdaDependencyKind = CXXRecordDecl::LDK_AlwaysDependent; } + // Determine the signature of the call operator. + TypeSourceInfo *MethodTyInfo; + bool ExplicitParams = true; + bool ExplicitResultType = true; + bool ContainsUnexpandedParameterPack = false; + SourceLocation EndLoc; + SmallVector 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(Context.getDefaultCallingConvention( + /*IsVariadic=*/false, /*IsCXXMethod=*/true)); + EPI.HasTrailingReturn = true; + EPI.TypeQuals.addConst(); + LangAS AS = getDefaultCXXMethodAddrSpace(); + if (AS != LangAS::Default) + EPI.TypeQuals.addAddressSpace(AS); + + // C++1y [expr.prim.lambda]: + // The lambda return type is 'auto', which is replaced by the + // trailing-return type if provided and/or deduced from 'return' + // statements + // We don't do this before C++1y, because we don't support deduced return + // types there. + QualType DefaultTypeForNoTrailingReturn = + getLangOpts().CPlusPlus14 ? Context.getAutoDeductType() + : Context.DependentTy; + QualType MethodTy = + Context.getFunctionType(DefaultTypeForNoTrailingReturn, None, 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.getOrCreateMethodQualifiers().SetTypeQual(DeclSpec::TQ_const, + SourceLocation()); + } + + MethodTyInfo = GetTypeForDeclarator(ParamInfo, CurScope); + assert(MethodTyInfo && "no type from lambda-declarator"); + EndLoc = ParamInfo.getSourceRange().getEnd(); + + ExplicitResultType = FTI.hasTrailingReturnType(); + + if (FTIHasNonVoidParameters(FTI)) { + Params.reserve(FTI.NumParams); + for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) + Params.push_back(cast(FTI.Params[i].Param)); + } + + // Check for unexpanded parameter packs in the method type. + if (MethodTyInfo->getType()->containsUnexpandedParameterPack()) + DiagnoseUnexpandedParameterPack(Intro.Range.getBegin(), MethodTyInfo, + UPPC_DeclarationType); + } + CXXRecordDecl *Class = createLambdaClosureType( - Intro.Range, nullptr, LambdaDependencyKind, Intro.Default); - LSI->Lambda = Class; + Intro.Range, MethodTyInfo, LambdaDependencyKind, Intro.Default); + CXXMethodDecl *Method = + startLambdaDefinition(Class, Intro.Range, MethodTyInfo, EndLoc, Params, + ParamInfo.getDeclSpec().getConstexprSpecifier(), + ParamInfo.getTrailingRequiresClause()); + if (ExplicitParams) + CheckCXXDefaultArguments(Method); - // C++11 [expr.prim.lambda]p5: - // The closure type for a lambda-expression has a public inline function - // call operator (13.5.4) whose parameters and return type are described - // by the lambda-expression's parameter-declaration-clause and - // trailing-return-type respectively. + // This represents the function body for the lambda function, check if we + // have to apply optnone due to a pragma. + AddRangeBasedOptnone(Method); - CXXMethodDecl *Method = CreateMethod(*this, Intro.Range, Class); - LSI->CallOperator = Method; - Method->setLexicalDeclContext(CurContext); + // code_seg attribute on lambda apply to the method. + if (Attr *A = getImplicitCodeSegOrSectionAttrForFunction(Method, /*IsDefinition=*/true)) + Method->addAttr(A); + + // Attributes on the lambda apply to the method. + ProcessDeclAttributes(CurScope, Method, ParamInfo); + + // CUDA lambdas get implicit host and device attributes. + if (getLangOpts().CUDA) + CUDASetLambdaAttrs(Method); + // OpenMP lambdas might get assumumption attributes. + if (LangOpts.OpenMP) + ActOnFinishedFunctionDefinitionInOpenMPAssumeScope(Method); + + // Number the lambda for linkage purposes if necessary. + handleLambdaNumbering(Class, Method); + + // Introduce the function call operator as the current declaration context. PushDeclContext(CurScope, Method); - bool ContainsUnexpandedParameterPack = false; + // Build the lambda scope. + buildLambdaScope(LSI, Method, Intro.Range, Intro.Default, Intro.DefaultLoc, + ExplicitParams, ExplicitResultType, !Method->isConst()); + + // C++11 [expr.prim.lambda]p9: + // A lambda-expression whose smallest enclosing scope is a block scope is a + // local lambda expression; any other lambda expression shall not have a + // capture-default or simple-capture in its lambda-introducer. + // + // For simple-captures, this is covered by the check below that any named + // entity is a variable that can be captured. + // + // For DR1632, we also allow a capture-default in any context where we can + // odr-use 'this' (in particular, in a default initializer for a non-static + // data member). + if (Intro.Default != LCD_None && !Class->getParent()->isFunctionOrMethod() && + (getCurrentThisType().isNull() || + CheckCXXThisCapture(SourceLocation(), /*Explicit*/true, + /*BuildAndDiagnose*/false))) + Diag(Intro.DefaultLoc, diag::err_capture_default_non_local); // Distinct capture names, for diagnostics. - llvm::SmallSet CaptureNames; + llvm::SmallSet CaptureNames; // Handle explicit captures. - SourceLocation PrevCaptureLoc = - Intro.Default == LCD_None ? Intro.Range.getBegin() : Intro.DefaultLoc; + SourceLocation PrevCaptureLoc + = Intro.Default == LCD_None? Intro.Range.getBegin() : Intro.DefaultLoc; for (auto C = Intro.Captures.begin(), E = Intro.Captures.end(); C != E; PrevCaptureLoc = C->Loc, ++C) { if (C->Kind == LCK_This || C->Kind == LCK_StarThis) { + if (C->Kind == LCK_StarThis) + Diag(C->Loc, !getLangOpts().CPlusPlus17 + ? diag::ext_star_this_lambda_capture_cxx17 + : diag::warn_cxx14_compat_star_this_lambda_capture); + + // 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(getLocForEndOfToken(PrevCaptureLoc), C->Loc)); + continue; + } + + // C++2a [expr.prim.lambda]p8: + // If a lambda-capture includes a capture-default that is =, + // each simple-capture of that lambda-capture shall be of the form + // "&identifier", "this", or "* this". [ Note: The form [&,this] is + // redundant but accepted for compatibility with ISO C++14. --end note ] + if (Intro.Default == LCD_ByCopy && C->Kind != LCK_StarThis) + Diag(C->Loc, !getLangOpts().CPlusPlus20 + ? diag::ext_equals_this_lambda_capture_cxx20 + : diag::warn_cxx17_compat_equals_this_lambda_capture); + + // 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, /*BuildAndDiagnose*/ true, + /*FunctionScopeIndexToStopAtPtr*/ nullptr, + C->Kind == LCK_StarThis); + if (!LSI->Captures.empty()) + LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange; + continue; } assert(C->Id && "missing identifier for capture"); + if (C->Init.isInvalid()) continue; @@ -1074,10 +1122,13 @@ void Sema::ActOnLambdaIntroducer(LambdaIntroducer &Intro, Scope *CurrentScope) { } Var = createLambdaInitCaptureVarDecl(C->Loc, C->InitCaptureType.get(), C->EllipsisLoc, C->Id, InitStyle, - C->Init.get(), Method); - assert(Var && "createLambdaInitCaptureVarDecl returned a null VarDecl?"); - CheckShadow(CurrentScope, Var); - PushOnScopeChains(Var, CurrentScope, false); + C->Init.get()); + // C++1y [expr.prim.lambda]p11: + // An init-capture behaves as if it declares and explicitly + // captures a variable [...] whose declarative region is the + // lambda-expression's compound-statement + if (Var) + PushOnScopeChains(Var, CurScope, false); } else { assert(C->InitKind == LambdaCaptureInitKind::NoInit && "init capture has valid but null init?"); @@ -1120,25 +1171,13 @@ void Sema::ActOnLambdaIntroducer(LambdaIntroducer &Intro, Scope *CurrentScope) { continue; } - // C++11 [expr.prim.lambda]p10: - // [...] 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(). - if (!Var) { - Diag(C->Loc, diag::err_capture_does_not_name_variable) << C->Id; - continue; - } - // C++11 [expr.prim.lambda]p8: // An identifier or this shall not appear more than once in a // lambda-capture. if (!CaptureNames.insert(C->Id).second) { - auto It = llvm::find_if(LSI->DelayedCaptures, [&Var](auto &&Pair) { - return Pair.second.Var == Var; - }); - if (It != LSI->DelayedCaptures.end()) { + if (Var && LSI->isCaptured(Var)) { Diag(C->Loc, diag::err_capture_more_than_once) - << C->Id << SourceRange(It->second.Loc) + << C->Id << SourceRange(LSI->getCapture(Var).getLocation()) << FixItHint::CreateRemoval( SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc)); } else @@ -1148,6 +1187,15 @@ void Sema::ActOnLambdaIntroducer(LambdaIntroducer &Intro, Scope *CurrentScope) { continue; } + // C++11 [expr.prim.lambda]p10: + // [...] 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(). + if (!Var) { + Diag(C->Loc, diag::err_capture_does_not_name_variable) << C->Id; + continue; + } + // Ignore invalid decls; they'll just confuse the code later. if (Var->isInvalidDecl()) continue; @@ -1175,247 +1223,22 @@ void Sema::ActOnLambdaIntroducer(LambdaIntroducer &Intro, Scope *CurrentScope) { ContainsUnexpandedParameterPack = true; } - if (Var) - LSI->DelayedCaptures[std::distance(Intro.Captures.begin(), C)] = - LambdaScopeInfo::DelayedCapture{Var, C->ExplicitRange.getBegin(), - C->Kind}; - } - - LSI->ContainsUnexpandedParameterPack |= ContainsUnexpandedParameterPack; - PopDeclContext(); -} - -static void AddExplicitCapturesToContext(Sema &S, LambdaScopeInfo *LSI, - LambdaIntroducer &Intro) { - SourceLocation PrevCaptureLoc; - for (auto C = Intro.Captures.begin(), E = Intro.Captures.end(); C != E; - PrevCaptureLoc = C->Loc, ++C) { - if (C->Kind == LCK_This || C->Kind == LCK_StarThis) { - if (C->Kind == LCK_StarThis) - S.Diag(C->Loc, !S.getLangOpts().CPlusPlus17 - ? diag::ext_star_this_lambda_capture_cxx17 - : diag::warn_cxx14_compat_star_this_lambda_capture); - - // C++11 [expr.prim.lambda]p8: - // An identifier or this shall not appear more than once in a - // lambda-capture. - if (LSI->isCXXThisCaptured()) { - S.Diag(C->Loc, diag::err_capture_more_than_once) - << "'this'" << SourceRange(LSI->getCXXThisCapture().getLocation()) - << FixItHint::CreateRemoval( - SourceRange(S.getLocForEndOfToken(PrevCaptureLoc), C->Loc)); - continue; - } - - // C++20 [expr.prim.lambda]p8: - // If a lambda-capture includes a capture-default that is =, - // each simple-capture of that lambda-capture shall be of the form - // "&identifier", "this", or "* this". [ Note: The form [&,this] is - // redundant but accepted for compatibility with ISO C++14. --end note ] - if (Intro.Default == LCD_ByCopy && C->Kind != LCK_StarThis) - S.Diag(C->Loc, - !S.getLangOpts().CPlusPlus20 - ? diag::ext_equals_this_lambda_capture_cxx20 - : diag::warn_cxx17_compat_equals_this_lambda_capture); - - // 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 = S.getCurrentThisType(); - if (ThisCaptureType.isNull()) { - S.Diag(C->Loc, diag::err_this_capture) << true; - continue; - } - S.CheckCXXThisCapture(C->Loc, true, true, nullptr, - C->Kind == LCK_StarThis); + if (C->Init.isUsable()) { + addInitCapture(LSI, Var); } else { - VarDecl *Var = - LSI->DelayedCaptures[std::distance(Intro.Captures.begin(), C)].Var; - if (!Var) - continue; - if (Var->isInitCapture() && C->Init.isUsable()) { - S.addInitCapture(LSI, Var); - S.PushOnScopeChains(Var, S.getCurScope(), false); - } else { - Sema::TryCaptureKind Kind = C->Kind == LCK_ByRef - ? Sema::TryCapture_ExplicitByRef - : Sema::TryCapture_ExplicitByVal; - S.tryCaptureVariable(Var, C->Loc, Kind, C->EllipsisLoc); - } + TryCaptureKind Kind = C->Kind == LCK_ByRef ? TryCapture_ExplicitByRef : + TryCapture_ExplicitByVal; + tryCaptureVariable(Var, C->Loc, Kind, EllipsisLoc); } if (!LSI->Captures.empty()) LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange; } - S.finishLambdaExplicitCaptures(LSI); -} - -void Sema::ActOnLambdaClosureQualifiers(LambdaIntroducer &Intro, - SourceLocation MutableLoc, - SourceLocation EndLoc, - const DeclSpec &DS) { - - LambdaScopeInfo *const LSI = getCurrentLambdaScopeUnsafe(*this); - LSI->Mutable = MutableLoc.isValid(); - LSI->BeforeLambdaQualifiersScope = false; - LSI->CallOperator->setConstexprKind(DS.getConstexprSpecifier()); - - // C++11 [expr.prim.lambda]p9: - // A lambda-expression whose smallest enclosing scope is a block scope is a - // local lambda expression; any other lambda expression shall not have a - // capture-default or simple-capture in its lambda-introducer. - // - // For simple-captures, this is covered by the check below that any named - // entity is a variable that can be captured. - // - // For DR1632, we also allow a capture-default in any context where we can - // odr-use 'this' (in particular, in a default initializer for a non-static - // data member). - if (Intro.Default != LCD_None && - !LSI->Lambda->getParent()->isFunctionOrMethod() && - (getCurrentThisType().isNull() || - CheckCXXThisCapture(SourceLocation(), /*Explicit*/ true, - /*BuildAndDiagnose*/ false))) - Diag(Intro.DefaultLoc, diag::err_capture_default_non_local); - - PushDeclContext(CurScope, LSI->CallOperator); - AddExplicitCapturesToContext(*this, LSI, Intro); -} - -void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro, - Declarator &ParamInfo, - Scope *CurScope) { - - LambdaScopeInfo *const LSI = getCurrentLambdaScopeUnsafe(*this); - - SmallVector Params; - bool ExplicitResultType; - - SourceLocation TypeLoc, LambdaLoc; - if (ParamInfo.getNumTypeObjects() == 0) { - LambdaLoc = TypeLoc = Intro.Range.getEnd(); - } else { - unsigned index; - ParamInfo.isFunctionDeclarator(index); - const auto &Object = ParamInfo.getTypeObject(index); - TypeLoc = - Object.Loc.isValid() ? Object.Loc : ParamInfo.getSourceRange().getEnd(); - LambdaLoc = ParamInfo.getSourceRange().getEnd(); - } - - CXXRecordDecl *Class = LSI->Lambda; - CXXMethodDecl *Method = LSI->CallOperator; - - if (auto *C = ParamInfo.getTrailingRequiresClause()) - Method->setTrailingRequiresClause(C); - - TemplateParameterList *TemplateParams = - getGenericLambdaTemplateParameterList(LSI, *this); - - auto DC = Method->getLexicalDeclContext(); - Method->setLexicalDeclContext(Class); - if (TemplateParams) { - FunctionTemplateDecl *const TemplateMethod = FunctionTemplateDecl::Create( - Context, Class, Method->getLocation(), Method->getDeclName(), - TemplateParams, Method); - TemplateMethod->setAccess(AS_public); - Method->setDescribedFunctionTemplate(TemplateMethod); - Class->addDecl(TemplateMethod); - TemplateMethod->setLexicalDeclContext(DC); - } else { - Class->addDecl(Method); - } - Method->setLexicalDeclContext(DC); - Class->setLambdaIsGeneric(TemplateParams); - - TypeSourceInfo *MethodTyInfo = getLambdaType( - *this, Intro, ParamInfo, getCurScope(), TypeLoc, ExplicitResultType); - - Class->setLambdaTypeInfo(MethodTyInfo); - Method->setInnerLocStart(LambdaLoc); - Method->setLocation(Intro.Range.getBegin()); - Method->setTypeSourceInfo(MethodTyInfo); - Method->setType(buildTypeForLambdaCallOperator(*this, Class, TemplateParams, - MethodTyInfo)); - Method->setConstexprKind(ParamInfo.getDeclSpec().getConstexprSpecifier()); - buildLambdaScopeReturnType(*this, LSI, Method, ExplicitResultType); - - LSI->ExplicitParams = ParamInfo.getNumTypeObjects() != 0; - - if (ParamInfo.isFunctionDeclarator() != 0 && - !FTIHasSingleVoidParameter(ParamInfo.getFunctionTypeInfo())) { - const auto &FTI = ParamInfo.getFunctionTypeInfo(); - Params.reserve(Params.size()); - for (unsigned I = 0; I < FTI.NumParams; ++I) { - auto *Param = cast(FTI.Params[I].Param); - Param->setScopeInfo(0, Params.size()); - Param->setOwningFunction(Method); - Params.push_back(Param); - } - } + finishLambdaExplicitCaptures(LSI); - ContextRAII ManglingContext(*this, Class->getDeclContext()); - - CheckParmsForFunctionDef(Params, /*CheckParameterNames=*/false); - - if (LSI->ExplicitParams) { - Method->setParams(Params); - CheckCXXDefaultArguments(Method); - } - - // This represents the function body for the lambda function, check if we - // have to apply optnone due to a pragma. - AddRangeBasedOptnone(Method); - - // code_seg attribute on lambda apply to the method. - if (Attr *A = getImplicitCodeSegOrSectionAttrForFunction( - Method, /*IsDefinition=*/true)) - Method->addAttr(A); - - // Attributes on the lambda apply to the method. - ProcessDeclAttributes(CurScope, Method, ParamInfo); - - // CUDA lambdas get implicit host and device attributes. - if (getLangOpts().CUDA) - CUDASetLambdaAttrs(Method); - - // OpenMP lambdas might get assumumption attributes. - if (LangOpts.OpenMP) - ActOnFinishedFunctionDefinitionInOpenMPAssumeScope(Method); - - handleLambdaNumbering(Class, Method); - - ManglingContext.pop(); - - for (auto &&C : LSI->DelayedCaptures) { - VarDecl *Var = C.second.Var; - if (Var && Var->isInitCapture()) { - PushOnScopeChains(Var, CurScope, false); - } - } - - LSI->DelayedCaptures.clear(); - - auto CheckRedefinition = [&](ParmVarDecl *Param) { - if (!Param->getIdentifier()) - return true; - for (const auto &Capture : Intro.Captures) { - if (Capture.Id == Param->getIdentifier()) { - Diag(Param->getLocation(), diag::err_parameter_shadow_capture); - Diag(Capture.Loc, diag::note_var_explicitly_captured_here) - << Capture.Id << true; - return false; - } - } - return true; - }; + LSI->ContainsUnexpandedParameterPack |= ContainsUnexpandedParameterPack; - for (auto &&P : Params) { - if (!P->getIdentifier()) - continue; - if (CheckRedefinition(P)) - CheckShadow(CurScope, P); - PushOnScopeChains(P, CurScope); - } + // Add lambda parameters into scope. + addLambdaParameters(Intro.Captures, Method, CurScope); // Enter a new evaluation context to insulate the lambda from any // cleanups from the enclosing full-expression. diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h index 5460f88228821..5eff7cfd7a253 100644 --- a/clang/lib/Sema/TreeTransform.h +++ b/clang/lib/Sema/TreeTransform.h @@ -13100,8 +13100,7 @@ TreeTransform::TransformLambdaExpr(LambdaExpr *E) { } VarDecl *NewVD = getSema().createLambdaInitCaptureVarDecl( OldVD->getLocation(), InitQualType, NewC.EllipsisLoc, - OldVD->getIdentifier(), OldVD->getInitStyle(), Init.get(), - getSema().CurContext); + OldVD->getIdentifier(), OldVD->getInitStyle(), Init.get()); if (!NewVD) { Invalid = true; break; diff --git a/clang/test/CXX/expr/expr.prim/expr.prim.lambda/p11-1y.cpp b/clang/test/CXX/expr/expr.prim/expr.prim.lambda/p11-1y.cpp index 67953c6a6f901..4a0cf39bc56b3 100644 --- a/clang/test/CXX/expr/expr.prim/expr.prim.lambda/p11-1y.cpp +++ b/clang/test/CXX/expr/expr.prim/expr.prim.lambda/p11-1y.cpp @@ -12,16 +12,16 @@ auto with_float_2 = [&f(f)] { // ok, refers to outer f using T = double&; }; -// Within the lambda-expression the identifier in the init-capture -// hides any declaration of the same name in scopes enclosing -// the lambda-expression. +// Within the lambda-expression's compound-statement, +// the identifier in the init-capture hides any declaration +// of the same name in scopes enclosing the lambda-expression. void hiding() { char c; (void) [c("foo")] { static_assert(sizeof(c) == sizeof(const char*), ""); }; - (void)[c("bar")]()->decltype(c) { // inner c - return "baz"; + (void) [c("bar")] () -> decltype(c) { // outer c, not init-capture + return "baz"; // expected-error {{cannot initialize}} }; } diff --git a/clang/test/SemaCXX/lambda-capture-type-deduction.cpp b/clang/test/SemaCXX/lambda-capture-type-deduction.cpp deleted file mode 100644 index 5915e1e8046ca..0000000000000 --- a/clang/test/SemaCXX/lambda-capture-type-deduction.cpp +++ /dev/null @@ -1,156 +0,0 @@ -// RUN: %clang_cc1 -std=c++2b -verify -fsyntax-only %s - -template -constexpr bool is_same = false; - -template -constexpr bool is_same = true; - -void f() { - - int y; - - static_assert(is_same decltype((x)) { return x; }())>); - - static_assert(is_same decltype((x)) { return x; }())>); - - static_assert(is_same decltype((y)) { return y; }())>); - - static_assert(is_same decltype((y)) { return y; }())>); - - static_assert(is_same decltype((y)) { return y; }())>); - - static_assert(is_same decltype((y)) { return y; }())>); - - auto ref = [&x = y]( - decltype([&](decltype(x)) { return 0; }) y) { - return x; - }; -} - -void test_noexcept() { - - int y; - - static_assert(noexcept([x = 1] noexcept(is_same) {}())); - static_assert(noexcept([x = 1] mutable noexcept(is_same) {}())); - static_assert(noexcept([y] noexcept(is_same) {}())); - static_assert(noexcept([y] mutable noexcept(is_same) {}())); - static_assert(noexcept([=] noexcept(is_same) {}())); - static_assert(noexcept([=] mutable noexcept(is_same) {}())); - static_assert(noexcept([&] noexcept(is_same) {}())); - static_assert(noexcept([&] mutable noexcept(is_same) {}())); - - static_assert(noexcept([&] mutable noexcept(!is_same) {}())); //expected-error {{static_assert failed due}} -} - -void test_requires() { - - int x; - - [x = 1]() requires is_same {} - (); - [x = 1]() mutable requires is_same {} - (); - [x]() requires is_same {} - (); - [x]() mutable requires is_same {} - (); - [=]() requires is_same {} - (); - [=]() mutable requires is_same {} - (); - [&]() requires is_same {} - (); - [&]() mutable requires is_same {} - (); - [&x]() requires is_same {} - (); - [&x]() mutable requires is_same {} - (); - - [x = 1]() requires is_same {} (); //expected-error {{no matching function for call to object of type}} \ - // expected-note {{candidate function not viable}} \ - // expected-note {{'is_same' evaluated to false}} - [x = 1]() mutable requires is_same {} (); // expected-error {{no matching function for call to object of type}} \ - // expected-note {{candidate function not viable}} \ - // expected-note {{'is_same' evaluated to false}} -} - -void err() { - int y, z; // expected-note 2{{declared here}} - auto implicit_tpl = [=]( // expected-note {{variable 'y' is captured here}} - decltype( - [&] { return 0; }) y) { //expected-error{{captured variable 'y' cannot appear here}} - return y; - }; - - auto init_tpl = [x = 1]( // expected-note{{explicitly captured here}} - decltype([&] { return 0; }) y) { // expected-error {{captured variable 'x' cannot appear here}} - return x; - }; - - auto implicit = [=]( // expected-note {{variable 'z' is captured here}} - decltype( - [&](decltype(z)) { return 0; }) z) { //expected-error{{captured variable 'z' cannot appear here}} - return z; - }; - - auto init = [x = 1]( // expected-note{{explicitly captured here}} - decltype([&](decltype(x)) { return 0; }) y) { // expected-error {{captured variable 'x' cannot appear here}} - return x; - }; - - auto use_before_params = [x = 1] // expected-note {{variable 'x' is explicitly captured here}} - requires(is_same) // expected-error {{captured variable 'x' cannot appear here}} - {}; - - auto use_before_params2 = [x = 1] // expected-note {{variable 'x' is explicitly captured here}} \ - // expected-error {{captured variable 'x' cannot appear here}} - {}; - - -} - -void nested() { - int x, y, z; //expected-note {{'x' declared here}} expected-note {{'z' declared here}} - (void)[&]( - decltype([&]( - decltype([=]( // expected-note {{variable 'x' is captured here}} - decltype([&]( - decltype([&](decltype(x)) {}) // expected-error{{captured variable 'x' cannot appear here}} - ) {})) {})) {})){}; - - (void)[&]( - decltype([&]( - decltype([&]( - decltype([&]( - decltype([&](decltype(y)) {})) {})) {})) {})){}; - - (void)[=]( - decltype([=]( - decltype([=]( - decltype([=]( // expected-note {{variable 'z' is captured here}} - decltype([&] {}) // expected-error{{captured variable 'z' cannot appear here}} - ) {})) {})) {})){}; -} - -template -void dependent(U&& u) { - [&]() requires is_same {}(); -} - -void test_dependent() { - int v = 0; - int & r = v; - const int & cr = v; - dependent(v); - dependent(r); - dependent(cr); -} diff --git a/clang/test/SemaCXX/warn-shadow-in-lambdas.cpp b/clang/test/SemaCXX/warn-shadow-in-lambdas.cpp index 9dddbf8b5f3b7..a772af049ab41 100644 --- a/clang/test/SemaCXX/warn-shadow-in-lambdas.cpp +++ b/clang/test/SemaCXX/warn-shadow-in-lambdas.cpp @@ -95,7 +95,7 @@ void foo(int param) { // expected-note 1+ {{previous declaration is here}} #ifdef AVOID auto l4 = [var = param] (int param) { ; }; // no warning #else - auto l4 = [var = param](int param) { ; }; // expected-warning 2{{declaration shadows a local variable}} + auto l4 = [var = param] (int param) { ; }; // expected-warning {{declaration shadows a local variable}} #endif // Make sure that inner lambdas work as well. diff --git a/clang/www/cxx_status.html b/clang/www/cxx_status.html index 44dfcbe98e2c1..5501d07f0e1ba 100755 --- a/clang/www/cxx_status.html +++ b/clang/www/cxx_status.html @@ -1356,7 +1356,7 @@

C++2b implementation status

Change scope of lambda trailing-return-type P2036R3 - Clang 15 + No Multidimensional subscript operator