Author: yronglin Date: 2024-09-12T06:29:48+08:00 New Revision: 060137038ab9246b377e190ae3c6f272fa57cbfc
URL: https://github.com/llvm/llvm-project/commit/060137038ab9246b377e190ae3c6f272fa57cbfc DIFF: https://github.com/llvm/llvm-project/commit/060137038ab9246b377e190ae3c6f272fa57cbfc.diff LOG: Reapply "[Clang][CWG1815] Support lifetime extension of temporary created by aggregate initialization using a default member initializer" (#108039) The PR reapply https://github.com/llvm/llvm-project/pull/97308. - Implement [CWG1815](https://wg21.link/CWG1815): Support lifetime extension of temporary created by aggregate initialization using a default member initializer. - Fix crash that introduced in https://github.com/llvm/llvm-project/pull/97308. In `InitListChecker::FillInEmptyInitForField`, when we enter rebuild-default-init context, we copy all the contents of the parent context to the current context, which will cause the `MaybeODRUseExprs` to be lost. But we don't need to copy the entire context, only the `DelayedDefaultInitializationContext` was required, which is used to build `SourceLocExpr`, etc. --------- Signed-off-by: yronglin <yronglin...@gmail.com> Added: clang/test/SemaCXX/PR97308.cpp Modified: clang/docs/ReleaseNotes.rst clang/include/clang/Basic/DiagnosticSemaKinds.td clang/include/clang/Sema/Sema.h clang/lib/Parse/ParseDecl.cpp clang/lib/Sema/CheckExprLifetime.cpp clang/lib/Sema/SemaExpr.cpp clang/lib/Sema/SemaExprCXX.cpp clang/lib/Sema/SemaInit.cpp clang/lib/Sema/SemaTemplateInstantiateDecl.cpp clang/lib/Sema/TreeTransform.h clang/test/AST/ast-dump-default-init-json.cpp clang/test/AST/ast-dump-default-init.cpp clang/test/Analysis/lifetime-extended-regions.cpp clang/test/CXX/drs/cwg16xx.cpp clang/test/CXX/drs/cwg18xx.cpp clang/test/CXX/special/class.temporary/p6.cpp clang/test/SemaCXX/constexpr-default-arg.cpp clang/test/SemaCXX/cxx11-default-member-initializers.cpp clang/test/SemaCXX/eval-crashes.cpp clang/www/cxx_dr_status.html Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 59ccdf1e15cd81..af6d1c5826a2fc 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -108,6 +108,9 @@ C++ Language Changes - Allow single element access of GCC vector/ext_vector_type object to be constant expression. Supports the `V.xyzw` syntax and other tidbits as seen in OpenCL. Selecting multiple elements is left as a future work. +- Implement `CWG1815 <https://wg21.link/CWG1815>`_. Support lifetime extension + of temporary created by aggregate initialization using a default member + initializer. - Accept C++26 user-defined ``static_assert`` messages in C++11 as an extension. diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index b160fee827a750..efdc058edca56d 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -10162,13 +10162,6 @@ def warn_dangling_pointer_assignment : Warning< "will be destroyed at the end of the full-expression">, InGroup<DanglingAssignment>; -def warn_unsupported_lifetime_extension : Warning< - "lifetime extension of " - "%select{temporary|backing array of initializer list}0 created " - "by aggregate initialization using a default member initializer " - "is not yet supported; lifetime of %select{temporary|backing array}0 " - "will end at the end of the full-expression">, InGroup<Dangling>; - // For non-floating point, expressions of the form x == x or x != x // should result in a warning, since these always evaluate to a constant. // Array comparisons have similar warnings diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h index 68c782a15c6f1b..99eef472223a00 100644 --- a/clang/include/clang/Sema/Sema.h +++ b/clang/include/clang/Sema/Sema.h @@ -6403,6 +6403,9 @@ class Sema final : public SemaBase { /// example, in a for-range initializer). bool InLifetimeExtendingContext = false; + /// Whether we should rebuild CXXDefaultArgExpr and CXXDefaultInitExpr. + bool RebuildDefaultArgOrDefaultInit = false; + // When evaluating immediate functions in the initializer of a default // argument or default member initializer, this is the declaration whose // default initializer is being evaluated and the location of the call @@ -7810,9 +7813,11 @@ class Sema final : public SemaBase { } bool isInLifetimeExtendingContext() const { - assert(!ExprEvalContexts.empty() && - "Must be in an expression evaluation context"); - return ExprEvalContexts.back().InLifetimeExtendingContext; + return currentEvaluationContext().InLifetimeExtendingContext; + } + + bool needsRebuildOfDefaultArgOrInit() const { + return currentEvaluationContext().RebuildDefaultArgOrDefaultInit; } bool isCheckingDefaultArgumentOrInitializer() const { @@ -7854,18 +7859,6 @@ class Sema final : public SemaBase { return Res; } - /// keepInLifetimeExtendingContext - Pull down InLifetimeExtendingContext - /// flag from previous context. - void keepInLifetimeExtendingContext() { - if (ExprEvalContexts.size() > 2 && - parentEvaluationContext().InLifetimeExtendingContext) { - auto &LastRecord = ExprEvalContexts.back(); - auto &PrevRecord = parentEvaluationContext(); - LastRecord.InLifetimeExtendingContext = - PrevRecord.InLifetimeExtendingContext; - } - } - DefaultedComparisonKind getDefaultedComparisonKind(const FunctionDecl *FD) { return getDefaultedFunctionKind(FD).asComparison(); } diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp index 61a1ca3da6bca0..1f56884be392d6 100644 --- a/clang/lib/Parse/ParseDecl.cpp +++ b/clang/lib/Parse/ParseDecl.cpp @@ -2509,8 +2509,9 @@ Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS, // P2718R0 - Lifetime extension in range-based for loops. if (getLangOpts().CPlusPlus23) { - auto &LastRecord = Actions.ExprEvalContexts.back(); + auto &LastRecord = Actions.currentEvaluationContext(); LastRecord.InLifetimeExtendingContext = true; + LastRecord.RebuildDefaultArgOrDefaultInit = true; } if (getLangOpts().OpenMP) diff --git a/clang/lib/Sema/CheckExprLifetime.cpp b/clang/lib/Sema/CheckExprLifetime.cpp index c8e703036c132c..77c73f47658fe1 100644 --- a/clang/lib/Sema/CheckExprLifetime.cpp +++ b/clang/lib/Sema/CheckExprLifetime.cpp @@ -896,11 +896,6 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path, enum PathLifetimeKind { /// Lifetime-extend along this path. Extend, - /// We should lifetime-extend, but we don't because (due to technical - /// limitations) we can't. This happens for default member initializers, - /// which we don't clone for every use, so we don't have a unique - /// MaterializeTemporaryExpr to update. - ShouldExtend, /// Do not lifetime extend along this path. NoExtend }; @@ -912,7 +907,7 @@ shouldLifetimeExtendThroughPath(const IndirectLocalPath &Path) { PathLifetimeKind Kind = PathLifetimeKind::Extend; for (auto Elem : Path) { if (Elem.Kind == IndirectLocalPathEntry::DefaultInit) - Kind = PathLifetimeKind::ShouldExtend; + return PathLifetimeKind::Extend; else if (Elem.Kind != IndirectLocalPathEntry::LambdaCaptureInit) return PathLifetimeKind::NoExtend; } @@ -1058,17 +1053,6 @@ static void checkExprLifetimeImpl(Sema &SemaRef, // Also visit the temporaries lifetime-extended by this initializer. return true; - case PathLifetimeKind::ShouldExtend: - // We're supposed to lifetime-extend the temporary along this path (per - // the resolution of DR1815), but we don't support that yet. - // - // FIXME: Properly handle this situation. Perhaps the easiest approach - // would be to clone the initializer expression on each use that would - // lifetime extend its temporaries. - SemaRef.Diag(DiagLoc, diag::warn_unsupported_lifetime_extension) - << RK << DiagRange; - break; - case PathLifetimeKind::NoExtend: // If the path goes through the initialization of a variable or field, // it can't possibly reach a temporary created in this full-expression. diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 32dac4440fb82a..8f3e15cc9a9bb7 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -5429,6 +5429,8 @@ struct EnsureImmediateInvocationInDefaultArgs EnsureImmediateInvocationInDefaultArgs(Sema &SemaRef) : TreeTransform(SemaRef) {} + bool AlwaysRebuild() { return true; } + // Lambda can only have immediate invocations in the default // args of their parameters, which is transformed upon calling the closure. // The body is not a subexpression, so we have nothing to do. @@ -5470,7 +5472,7 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, assert(Param->hasDefaultArg() && "can't build nonexistent default arg"); bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer(); - bool InLifetimeExtendingContext = isInLifetimeExtendingContext(); + bool NeedRebuild = needsRebuildOfDefaultArgOrInit(); std::optional<ExpressionEvaluationContextRecord::InitializationContext> InitializationContext = OutermostDeclarationWithDelayedImmediateInvocations(); @@ -5506,13 +5508,15 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, // Rewrite the call argument that was created from the corresponding // parameter's default argument. - if (V.HasImmediateCalls || InLifetimeExtendingContext) { + if (V.HasImmediateCalls || + (NeedRebuild && isa_and_present<ExprWithCleanups>(Param->getInit()))) { if (V.HasImmediateCalls) ExprEvalContexts.back().DelayedDefaultInitializationContext = { CallLoc, Param, CurContext}; // Pass down lifetime extending flag, and collect temporaries in // CreateMaterializeTemporaryExpr when we rewrite the call argument. - keepInLifetimeExtendingContext(); + currentEvaluationContext().InLifetimeExtendingContext = + parentEvaluationContext().InLifetimeExtendingContext; EnsureImmediateInvocationInDefaultArgs Immediate(*this); ExprResult Res; runWithSufficientStackSpace(CallLoc, [&] { @@ -5558,7 +5562,7 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) { Expr *Init = nullptr; bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer(); - + bool NeedRebuild = needsRebuildOfDefaultArgOrInit(); EnterExpressionEvaluationContext EvalContext( *this, ExpressionEvaluationContext::PotentiallyEvaluated, Field); @@ -5593,12 +5597,27 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) { ImmediateCallVisitor V(getASTContext()); if (!NestedDefaultChecking) V.TraverseDecl(Field); - if (V.HasImmediateCalls) { + + // CWG1815 + // Support lifetime extension of temporary created by aggregate + // initialization using a default member initializer. We should rebuild + // the initializer in a lifetime extension context if the initializer + // expression is an ExprWithCleanups. Then make sure the normal lifetime + // extension code recurses into the default initializer and does lifetime + // extension when warranted. + bool ContainsAnyTemporaries = + isa_and_present<ExprWithCleanups>(Field->getInClassInitializer()); + if (Field->getInClassInitializer() && + !Field->getInClassInitializer()->containsErrors() && + (V.HasImmediateCalls || (NeedRebuild && ContainsAnyTemporaries))) { ExprEvalContexts.back().DelayedDefaultInitializationContext = {Loc, Field, CurContext}; ExprEvalContexts.back().IsCurrentlyCheckingDefaultArgumentOrInitializer = NestedDefaultChecking; - + // Pass down lifetime extending flag, and collect temporaries in + // CreateMaterializeTemporaryExpr when we rewrite the call argument. + currentEvaluationContext().InLifetimeExtendingContext = + parentEvaluationContext().InLifetimeExtendingContext; EnsureImmediateInvocationInDefaultArgs Immediate(*this); ExprResult Res; runWithSufficientStackSpace(Loc, [&] { @@ -17675,11 +17694,10 @@ void Sema::PopExpressionEvaluationContext() { // Append the collected materialized temporaries into previous context before // exit if the previous also is a lifetime extending context. - auto &PrevRecord = parentEvaluationContext(); if (getLangOpts().CPlusPlus23 && Rec.InLifetimeExtendingContext && - PrevRecord.InLifetimeExtendingContext && + parentEvaluationContext().InLifetimeExtendingContext && !Rec.ForRangeLifetimeExtendTemps.empty()) { - PrevRecord.ForRangeLifetimeExtendTemps.append( + parentEvaluationContext().ForRangeLifetimeExtendTemps.append( Rec.ForRangeLifetimeExtendTemps); } diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp index a33854a211ce83..ac3fe6ab8f9bd0 100644 --- a/clang/lib/Sema/SemaExprCXX.cpp +++ b/clang/lib/Sema/SemaExprCXX.cpp @@ -1540,9 +1540,6 @@ Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo, bool ListInitialization) { QualType Ty = TInfo->getType(); SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc(); - - assert((!ListInitialization || Exprs.size() == 1) && - "List initialization must have exactly one expression."); SourceRange FullRange = SourceRange(TyBeginLoc, RParenOrBraceLoc); InitializedEntity Entity = diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp index 7dc17187524621..d21b8cb8c04e63 100644 --- a/clang/lib/Sema/SemaInit.cpp +++ b/clang/lib/Sema/SemaInit.cpp @@ -750,8 +750,21 @@ void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field, if (Field->hasInClassInitializer()) { if (VerifyOnly) return; - - ExprResult DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field); + ExprResult DIE; + { + // Enter a default initializer rebuild context, then we can support + // lifetime extension of temporary created by aggregate initialization + // using a default member initializer. + // CWG1815 (https://wg21.link/CWG1815). + EnterExpressionEvaluationContext RebuildDefaultInit( + SemaRef, Sema::ExpressionEvaluationContext::PotentiallyEvaluated); + SemaRef.currentEvaluationContext().RebuildDefaultArgOrDefaultInit = + true; + SemaRef.currentEvaluationContext().DelayedDefaultInitializationContext = + SemaRef.parentEvaluationContext() + .DelayedDefaultInitializationContext; + DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field); + } if (DIE.isInvalid()) { hadError = true; return; @@ -7521,10 +7534,8 @@ Sema::CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary, // are done in both CreateMaterializeTemporaryExpr and MaybeBindToTemporary, // but there may be a chance to merge them. Cleanup.setExprNeedsCleanups(false); - if (isInLifetimeExtendingContext()) { - auto &Record = ExprEvalContexts.back(); - Record.ForRangeLifetimeExtendTemps.push_back(MTE); - } + if (isInLifetimeExtendingContext()) + currentEvaluationContext().ForRangeLifetimeExtendTemps.push_back(MTE); return MTE; } diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp index 6df412cbb09c83..bb311e38409280 100644 --- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp +++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp @@ -5481,7 +5481,10 @@ void Sema::InstantiateVariableInitializer( EnterExpressionEvaluationContext Evaluated( *this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated, Var); - keepInLifetimeExtendingContext(); + currentEvaluationContext().InLifetimeExtendingContext = + parentEvaluationContext().InLifetimeExtendingContext; + currentEvaluationContext().RebuildDefaultArgOrDefaultInit = + parentEvaluationContext().RebuildDefaultArgOrDefaultInit; // Instantiate the initializer. ExprResult Init; diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h index 0daf620b4123e4..4bbc024587915c 100644 --- a/clang/lib/Sema/TreeTransform.h +++ b/clang/lib/Sema/TreeTransform.h @@ -4254,7 +4254,10 @@ ExprResult TreeTransform<Derived>::TransformInitializer(Expr *Init, getSema(), EnterExpressionEvaluationContext::InitList, Construct->isListInitialization()); - getSema().keepInLifetimeExtendingContext(); + getSema().currentEvaluationContext().InLifetimeExtendingContext = + getSema().parentEvaluationContext().InLifetimeExtendingContext; + getSema().currentEvaluationContext().RebuildDefaultArgOrDefaultInit = + getSema().parentEvaluationContext().RebuildDefaultArgOrDefaultInit; SmallVector<Expr*, 8> NewArgs; bool ArgChanged = false; if (getDerived().TransformExprs(Construct->getArgs(), Construct->getNumArgs(), @@ -8924,8 +8927,9 @@ TreeTransform<Derived>::TransformCXXForRangeStmt(CXXForRangeStmt *S) { // P2718R0 - Lifetime extension in range-based for loops. if (getSema().getLangOpts().CPlusPlus23) { - auto &LastRecord = getSema().ExprEvalContexts.back(); + auto &LastRecord = getSema().currentEvaluationContext(); LastRecord.InLifetimeExtendingContext = true; + LastRecord.RebuildDefaultArgOrDefaultInit = true; } StmtResult Init = S->getInit() ? getDerived().TransformStmt(S->getInit()) : StmtResult(); @@ -14443,6 +14447,13 @@ TreeTransform<Derived>::TransformCXXTemporaryObjectExpr( if (TransformExprs(E->getArgs(), E->getNumArgs(), true, Args, &ArgumentChanged)) return ExprError(); + + if (E->isListInitialization() && !E->isStdInitListInitialization()) { + ExprResult Res = RebuildInitList(E->getBeginLoc(), Args, E->getEndLoc()); + if (Res.isInvalid()) + return ExprError(); + Args = {Res.get()}; + } } if (!getDerived().AlwaysRebuild() && @@ -14454,12 +14465,9 @@ TreeTransform<Derived>::TransformCXXTemporaryObjectExpr( return SemaRef.MaybeBindToTemporary(E); } - // FIXME: We should just pass E->isListInitialization(), but we're not - // prepared to handle list-initialization without a child InitListExpr. SourceLocation LParenLoc = T->getTypeLoc().getEndLoc(); return getDerived().RebuildCXXTemporaryObjectExpr( - T, LParenLoc, Args, E->getEndLoc(), - /*ListInitialization=*/LParenLoc.isInvalid()); + T, LParenLoc, Args, E->getEndLoc(), E->isListInitialization()); } template<typename Derived> diff --git a/clang/test/AST/ast-dump-default-init-json.cpp b/clang/test/AST/ast-dump-default-init-json.cpp index 1058b4e3ea4d93..f4949a9c9eedf4 100644 --- a/clang/test/AST/ast-dump-default-init-json.cpp +++ b/clang/test/AST/ast-dump-default-init-json.cpp @@ -789,10 +789,10 @@ void test() { // CHECK-NEXT: "valueCategory": "lvalue", // CHECK-NEXT: "extendingDecl": { // CHECK-NEXT: "id": "0x{{.*}}", -// CHECK-NEXT: "kind": "FieldDecl", -// CHECK-NEXT: "name": "a", +// CHECK-NEXT: "kind": "VarDecl", +// CHECK-NEXT: "name": "b", // CHECK-NEXT: "type": { -// CHECK-NEXT: "qualType": "const A &" +// CHECK-NEXT: "qualType": "B" // CHECK-NEXT: } // CHECK-NEXT: }, // CHECK-NEXT: "storageDuration": "automatic", diff --git a/clang/test/AST/ast-dump-default-init.cpp b/clang/test/AST/ast-dump-default-init.cpp index 15b29f04bf21bf..26864fbf15424d 100644 --- a/clang/test/AST/ast-dump-default-init.cpp +++ b/clang/test/AST/ast-dump-default-init.cpp @@ -13,7 +13,7 @@ void test() { } // CHECK: -CXXDefaultInitExpr 0x{{[^ ]*}} <{{.*}}> 'const A' lvalue has rewritten init // CHECK-NEXT: `-ExprWithCleanups 0x{{[^ ]*}} <{{.*}}> 'const A' lvalue -// CHECK-NEXT: `-MaterializeTemporaryExpr 0x{{[^ ]*}} <{{.*}}> 'const A' lvalue extended by Field 0x{{[^ ]*}} 'a' 'const A &' +// CHECK-NEXT: `-MaterializeTemporaryExpr 0x{{[^ ]*}} <{{.*}}> 'const A' lvalue extended by Var 0x{{[^ ]*}} 'b' 'B' // CHECK-NEXT: `-ImplicitCastExpr 0x{{[^ ]*}} <{{.*}}> 'const A' <NoOp> // CHECK-NEXT: `-CXXFunctionalCastExpr 0x{{[^ ]*}} <{{.*}}> 'A' functional cast to A <NoOp> // CHECK-NEXT: `-InitListExpr 0x{{[^ ]*}} <{{.*}}> 'A' diff --git a/clang/test/Analysis/lifetime-extended-regions.cpp b/clang/test/Analysis/lifetime-extended-regions.cpp index 4e98bd4b0403eb..4458ad294af7cb 100644 --- a/clang/test/Analysis/lifetime-extended-regions.cpp +++ b/clang/test/Analysis/lifetime-extended-regions.cpp @@ -120,10 +120,11 @@ void aggregateWithReferences() { clang_analyzer_dump(viaReference); // expected-warning-re {{&lifetime_extended_object{RefAggregate, viaReference, S{{[0-9]+}}} }} clang_analyzer_dump(viaReference.rx); // expected-warning-re {{&lifetime_extended_object{int, viaReference, S{{[0-9]+}}} }} clang_analyzer_dump(viaReference.ry); // expected-warning-re {{&lifetime_extended_object{Composite, viaReference, S{{[0-9]+}}} }} - - // clang does not currently implement extending lifetime of object bound to reference members of aggregates, - // that are created from default member initializer (see `warn_unsupported_lifetime_extension` from `-Wdangling`) - RefAggregate defaultInitExtended{i}; // clang-bug does not extend `Composite` + + // FIXME: clang currently support extending lifetime of object bound to reference members of aggregates, + // that are created from default member initializer. But CFG and ExprEngine need to be updated to address this change. + // The following expect warning: {{&lifetime_extended_object{Composite, defaultInitExtended, S{{[0-9]+}}} }} + RefAggregate defaultInitExtended{i}; clang_analyzer_dump(defaultInitExtended.ry); // expected-warning {{Unknown }} } diff --git a/clang/test/CXX/drs/cwg16xx.cpp b/clang/test/CXX/drs/cwg16xx.cpp index cf6b45ceabf2cc..95e241f0d03e9b 100644 --- a/clang/test/CXX/drs/cwg16xx.cpp +++ b/clang/test/CXX/drs/cwg16xx.cpp @@ -449,6 +449,27 @@ namespace cwg1696 { // cwg1696: 7 // since-cxx14-note@-2 {{default member initializer declared here}} }; A a{a, a}; + + struct A1 { + A1() : v(42) {} + // since-cxx14-error@-1 {{reference member 'v' binds to a temporary object whose lifetime would be shorter than the lifetime of the constructed object}} + // since-cxx14-note@#cwg1696-A1 {{reference member declared here}} + const int &v; // #cwg1696-A1 + }; + + struct A2 { + A2() = default; + // since-cxx14-error@-1 {{reference member 'v' binds to a temporary object whose lifetime would be shorter than the lifetime of the constructed object}} + // since-cxx14-note-re@#cwg1696-A2-b {{in defaulted default constructor for {{.*}} first required here}} + // since-cxx14-note@#cwg1696-A2-a {{initializing field 'v' with default member initializer}} + A2(int v) : v(v) {} + // since-cxx14-warning@-1 {{binding reference member 'v' to stack allocated parameter 'v'}} + // since-cxx14-note@#cwg1696-A2-a {{reference member declared here}} + const int &v = 42; // #cwg1696-A2-a + }; + A2 a1; // #cwg1696-A2-b + + A2 a2(1); // OK, unfortunately #endif } @@ -483,8 +504,6 @@ namespace cwg1696 { // cwg1696: 7 const A &a = A(); // #cwg1696-D1-a }; D1 d1 = {}; // #cwg1696-d1 - // since-cxx14-warning@-1 {{lifetime extension of temporary created by aggregate initialization using a default member initializer is not yet supported; lifetime of temporary will end at the end of the full-expression}} - // since-cxx14-note@#cwg1696-D1-a {{initializing field 'a' with default member initializer}} struct D2 { const A &a = A(); // #cwg1696-D2-a diff --git a/clang/test/CXX/drs/cwg18xx.cpp b/clang/test/CXX/drs/cwg18xx.cpp index 61b7faa96a9fbb..7f0fb8cf589d48 100644 --- a/clang/test/CXX/drs/cwg18xx.cpp +++ b/clang/test/CXX/drs/cwg18xx.cpp @@ -206,19 +206,28 @@ namespace cwg1814 { // cwg1814: yes #endif } -namespace cwg1815 { // cwg1815: no +namespace cwg1815 { // cwg1815: 20 #if __cplusplus >= 201402L - // FIXME: needs codegen test - struct A { int &&r = 0; }; // #cwg1815-A + struct A { int &&r = 0; }; A a = {}; - // since-cxx14-warning@-1 {{lifetime extension of temporary created by aggregate initialization using a default member initializer is not yet supported; lifetime of temporary will end at the end of the full-expression}} FIXME - // since-cxx14-note@#cwg1815-A {{initializing field 'r' with default member initializer}} struct B { int &&r = 0; }; // #cwg1815-B // since-cxx14-error@-1 {{reference member 'r' binds to a temporary object whose lifetime would be shorter than the lifetime of the constructed object}} // since-cxx14-note@#cwg1815-B {{initializing field 'r' with default member initializer}} // since-cxx14-note@#cwg1815-b {{in implicit default constructor for 'cwg1815::B' first required here}} B b; // #cwg1815-b + +#if __cplusplus >= 201703L + struct C { const int &r = 0; }; + constexpr C c = {}; // OK, since cwg1815 + static_assert(c.r == 0); + + constexpr int f() { + A a = {}; // OK, since cwg1815 + return a.r; + } + static_assert(f() == 0); +#endif #endif } diff --git a/clang/test/CXX/special/class.temporary/p6.cpp b/clang/test/CXX/special/class.temporary/p6.cpp index 5554363cc69abb..a6d2adfd1fd2c5 100644 --- a/clang/test/CXX/special/class.temporary/p6.cpp +++ b/clang/test/CXX/special/class.temporary/p6.cpp @@ -269,6 +269,40 @@ void init_capture_init_list() { // CHECK: } } +void check_dr1815() { // dr1815: yes +#if __cplusplus >= 201402L + + struct A { + int &&r = 0; + ~A() {} + }; + + struct B { + A &&a = A{}; + ~B() {} + }; + B a = {}; + + // CHECK: call {{.*}}block_scope_begin_function + extern void block_scope_begin_function(); + extern void block_scope_end_function(); + block_scope_begin_function(); + { + // CHECK: call void @_ZZ12check_dr1815vEN1BD1Ev + // CHECK: call void @_ZZ12check_dr1815vEN1AD1Ev + B b = {}; + } + // CHECK: call {{.*}}block_scope_end_function + block_scope_end_function(); + + // CHECK: call {{.*}}some_other_function + extern void some_other_function(); + some_other_function(); + // CHECK: call void @_ZZ12check_dr1815vEN1BD1Ev + // CHECK: call void @_ZZ12check_dr1815vEN1AD1Ev +#endif +} + namespace P2718R0 { namespace basic { template <typename E> using T2 = std::list<E>; diff --git a/clang/test/SemaCXX/PR97308.cpp b/clang/test/SemaCXX/PR97308.cpp new file mode 100644 index 00000000000000..7f550bc15d741c --- /dev/null +++ b/clang/test/SemaCXX/PR97308.cpp @@ -0,0 +1,21 @@ +// RUN: %clang_cc1 -o - -emit-llvm -triple x86_64-linux-gnu %s + +// Check there are no crash issue CodeGen action. +// https://github.com/llvm/llvm-project/pull/97308 +struct a { +} constexpr b; +class c { +public: + c(a); +}; +class B { +public: + using d = int; + struct e { + enum { f } g; + int h; + c i; + d j{}; + }; +}; +B::e k{B::e::f, int(), b}; diff --git a/clang/test/SemaCXX/constexpr-default-arg.cpp b/clang/test/SemaCXX/constexpr-default-arg.cpp index ec9b2927880bdf..901123bfb359ff 100644 --- a/clang/test/SemaCXX/constexpr-default-arg.cpp +++ b/clang/test/SemaCXX/constexpr-default-arg.cpp @@ -32,8 +32,8 @@ void test_default_arg2() { } // Check that multiple CXXDefaultInitExprs don't cause an assertion failure. -struct A { int &&r = 0; }; // expected-note 2{{default member initializer}} +struct A { int &&r = 0; }; struct B { A x, y; }; -B b = {}; // expected-warning 2{{lifetime extension of temporary created by aggregate initialization using a default member initializer is not yet supported}} +B b = {}; // expected-no-diagnostics } diff --git a/clang/test/SemaCXX/cxx11-default-member-initializers.cpp b/clang/test/SemaCXX/cxx11-default-member-initializers.cpp index dd8e9c6b7fc11f..5e26c3a3b82cd5 100644 --- a/clang/test/SemaCXX/cxx11-default-member-initializers.cpp +++ b/clang/test/SemaCXX/cxx11-default-member-initializers.cpp @@ -27,6 +27,103 @@ class MemInit { C m = s; }; +namespace std { +typedef decltype(sizeof(int)) size_t; + +// libc++'s implementation +template <class _E> class initializer_list { + const _E *__begin_; + size_t __size_; + + initializer_list(const _E *__b, size_t __s) : __begin_(__b), __size_(__s) {} + +public: + typedef _E value_type; + typedef const _E &reference; + typedef const _E &const_reference; + typedef size_t size_type; + + typedef const _E *iterator; + typedef const _E *const_iterator; + + initializer_list() : __begin_(nullptr), __size_(0) {} + + size_t size() const { return __size_; } + const _E *begin() const { return __begin_; } + const _E *end() const { return __begin_ + __size_; } +}; +} // namespace std + +#if __cplusplus >= 201703L + +// Test CXXDefaultInitExpr rebuild issue in +// https://github.com/llvm/llvm-project/pull/87933 +namespace test_rebuild { +template <typename T, int> class C { +public: + C(std::initializer_list<T>); +}; + +template <typename T> using Ptr = __remove_pointer(T) *; +template <typename T> C(T) -> C<Ptr<T>, sizeof(T)>; + +class A { +public: + template <typename T1, typename T2> T1 *some_func(T2 &&); +}; + +struct B : A { + int *ar = some_func<int>(C{some_func<int>(0)}); + B() {} +}; + +int TestBody_got; +template <int> class Vector { +public: + Vector(std::initializer_list<int>); +}; +template <typename... Ts> Vector(Ts...) -> Vector<sizeof...(Ts)>; +class ProgramBuilder { +public: + template <typename T, typename ARGS> int *create(ARGS); +}; + +struct TypeTest : ProgramBuilder { + int *str_f16 = create<int>(Vector{0}); + TypeTest() {} +}; +class TypeTest_Element_Test : TypeTest { + void TestBody(); +}; +void TypeTest_Element_Test::TestBody() { + int *expect = str_f16; + &TestBody_got != expect; // expected-warning {{inequality comparison result unused}} +} +} // namespace test_rebuild + +// Test CXXDefaultInitExpr rebuild issue in +// https://github.com/llvm/llvm-project/pull/92527 +namespace test_rebuild2 { +struct F { + int g; +}; +struct H {}; +struct I { + I(const F &); + I(H); +}; +struct L { + I i = I({.g = 0}); +}; +struct N : L {}; + +void f() { + delete new L; // Ok + delete new N; // Ok +} +} // namespace test_rebuild2 +#endif // __cplusplus >= 201703L + #if __cplusplus >= 202002L // This test ensures cleanup expressions are correctly produced // in the presence of default member initializers. diff --git a/clang/test/SemaCXX/eval-crashes.cpp b/clang/test/SemaCXX/eval-crashes.cpp index 0865dafe4bf92a..21e05f19be0caa 100644 --- a/clang/test/SemaCXX/eval-crashes.cpp +++ b/clang/test/SemaCXX/eval-crashes.cpp @@ -25,11 +25,9 @@ namespace pr33140_0b { } namespace pr33140_2 { - // FIXME: The declaration of 'b' below should lifetime-extend two int - // temporaries. - struct A { int &&r = 0; }; // expected-note 2{{initializing field 'r' with default member initializer}} + struct A { int &&r = 0; }; struct B { A x, y; }; - B b = {}; // expected-warning 2{{lifetime extension of temporary created by aggregate initialization using a default member initializer is not yet supported}} + B b = {}; } namespace pr33140_3 { diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html index b638f0ff30bcce..f036fc5add2413 100755 --- a/clang/www/cxx_dr_status.html +++ b/clang/www/cxx_dr_status.html @@ -10717,7 +10717,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td><a href="https://cplusplus.github.io/CWG/issues/1815.html";>1815</a></td> <td>CD4</td> <td>Lifetime extension in aggregate initialization</td> - <td class="none" align="center">No</td> + <td class="unreleased" align="center">Clang 20</td> </tr> <tr id="1816"> <td><a href="https://cplusplus.github.io/CWG/issues/1816.html";>1816</a></td> _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
