[clang] cca54e3 - Revert "Reapply "[Clang][CWG1815] Support lifetime extension of temporary created by aggregate initialization using a default member initializer" (#97308)"
Martin Storsjö via cfe-commits
cfe-commits at lists.llvm.org
Mon Sep 9 05:10:48 PDT 2024
Author: Martin Storsjö
Date: 2024-09-09T15:09:45+03:00
New Revision: cca54e347ac34912cdfb9983533c61836db135e0
URL: https://github.com/llvm/llvm-project/commit/cca54e347ac34912cdfb9983533c61836db135e0
DIFF: https://github.com/llvm/llvm-project/commit/cca54e347ac34912cdfb9983533c61836db135e0.diff
LOG: Revert "Reapply "[Clang][CWG1815] Support lifetime extension of temporary created by aggregate initialization using a default member initializer" (#97308)"
This reverts commit 45c8766973bb3bb73dd8d996231e114dcf45df9f
and 049512e39d96995cb373a76cf2d009a86eaf3aab.
This change triggers failed asserts on inputs like this:
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};
Compiled like this:
clang -target x86_64-linux-gnu -c repro.cpp
clang: ../../clang/lib/CodeGen/CGExpr.cpp:3105: clang::CodeGen::LValue
clang::CodeGen::CodeGenFunction::EmitDeclRefLValue(const clang::DeclRefExpr*):
Assertion `(ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() ||
!E->getLocation().isValid()) && "Should not use decl without marking it used!"' failed.
Added:
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 07f3544e2324e3..250821a9f9c45c 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -108,9 +108,6 @@ 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 4609d2ec2b7209..58819a64813fce 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -10159,6 +10159,13 @@ 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 ac4c11964b126f..68c782a15c6f1b 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -6403,9 +6403,6 @@ 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
@@ -7813,11 +7810,9 @@ class Sema final : public SemaBase {
}
bool isInLifetimeExtendingContext() const {
- return currentEvaluationContext().InLifetimeExtendingContext;
- }
-
- bool needRebuildDefaultArgOrInit() const {
- return currentEvaluationContext().RebuildDefaultArgOrDefaultInit;
+ assert(!ExprEvalContexts.empty() &&
+ "Must be in an expression evaluation context");
+ return ExprEvalContexts.back().InLifetimeExtendingContext;
}
bool isCheckingDefaultArgumentOrInitializer() const {
@@ -7859,6 +7854,18 @@ 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 1f56884be392d6..61a1ca3da6bca0 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2509,9 +2509,8 @@ Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS,
// P2718R0 - Lifetime extension in range-based for loops.
if (getLangOpts().CPlusPlus23) {
- auto &LastRecord = Actions.currentEvaluationContext();
+ auto &LastRecord = Actions.ExprEvalContexts.back();
LastRecord.InLifetimeExtendingContext = true;
- LastRecord.RebuildDefaultArgOrDefaultInit = true;
}
if (getLangOpts().OpenMP)
diff --git a/clang/lib/Sema/CheckExprLifetime.cpp b/clang/lib/Sema/CheckExprLifetime.cpp
index f62e18543851c1..f1507ebb9a5068 100644
--- a/clang/lib/Sema/CheckExprLifetime.cpp
+++ b/clang/lib/Sema/CheckExprLifetime.cpp
@@ -871,6 +871,11 @@ 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
};
@@ -882,7 +887,7 @@ shouldLifetimeExtendThroughPath(const IndirectLocalPath &Path) {
PathLifetimeKind Kind = PathLifetimeKind::Extend;
for (auto Elem : Path) {
if (Elem.Kind == IndirectLocalPathEntry::DefaultInit)
- return PathLifetimeKind::Extend;
+ Kind = PathLifetimeKind::ShouldExtend;
else if (Elem.Kind != IndirectLocalPathEntry::LambdaCaptureInit)
return PathLifetimeKind::NoExtend;
}
@@ -1029,6 +1034,17 @@ 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 30e5fe4543bcaa..32dac4440fb82a 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -5429,8 +5429,6 @@ 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.
@@ -5472,7 +5470,7 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
assert(Param->hasDefaultArg() && "can't build nonexistent default arg");
bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer();
- bool NeedRebuild = needRebuildDefaultArgOrInit();
+ bool InLifetimeExtendingContext = isInLifetimeExtendingContext();
std::optional<ExpressionEvaluationContextRecord::InitializationContext>
InitializationContext =
OutermostDeclarationWithDelayedImmediateInvocations();
@@ -5508,15 +5506,13 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
// Rewrite the call argument that was created from the corresponding
// parameter's default argument.
- if (V.HasImmediateCalls ||
- (NeedRebuild && isa_and_present<ExprWithCleanups>(Param->getInit()))) {
+ if (V.HasImmediateCalls || InLifetimeExtendingContext) {
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.
- currentEvaluationContext().InLifetimeExtendingContext =
- parentEvaluationContext().InLifetimeExtendingContext;
+ keepInLifetimeExtendingContext();
EnsureImmediateInvocationInDefaultArgs Immediate(*this);
ExprResult Res;
runWithSufficientStackSpace(CallLoc, [&] {
@@ -5562,7 +5558,7 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
Expr *Init = nullptr;
bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer();
- bool NeedRebuild = needRebuildDefaultArgOrInit();
+
EnterExpressionEvaluationContext EvalContext(
*this, ExpressionEvaluationContext::PotentiallyEvaluated, Field);
@@ -5597,27 +5593,12 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
ImmediateCallVisitor V(getASTContext());
if (!NestedDefaultChecking)
V.TraverseDecl(Field);
-
- // 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))) {
+ if (V.HasImmediateCalls) {
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, [&] {
@@ -17694,10 +17675,11 @@ 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 &&
- parentEvaluationContext().InLifetimeExtendingContext &&
+ PrevRecord.InLifetimeExtendingContext &&
!Rec.ForRangeLifetimeExtendTemps.empty()) {
- parentEvaluationContext().ForRangeLifetimeExtendTemps.append(
+ PrevRecord.ForRangeLifetimeExtendTemps.append(
Rec.ForRangeLifetimeExtendTemps);
}
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index e086c601107041..14feafd1e6b17f 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -1540,6 +1540,9 @@ 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 de2686e447892e..7dc17187524621 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -750,20 +750,8 @@ void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
if (Field->hasInClassInitializer()) {
if (VerifyOnly)
return;
- 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);
- // Just copy previous record, make sure we haven't forget anything.
- SemaRef.currentEvaluationContext() = SemaRef.parentEvaluationContext();
- SemaRef.currentEvaluationContext().RebuildDefaultArgOrDefaultInit =
- true;
- DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field);
- }
+
+ ExprResult DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field);
if (DIE.isInvalid()) {
hadError = true;
return;
@@ -7533,8 +7521,10 @@ 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())
- currentEvaluationContext().ForRangeLifetimeExtendTemps.push_back(MTE);
+ if (isInLifetimeExtendingContext()) {
+ auto &Record = ExprEvalContexts.back();
+ Record.ForRangeLifetimeExtendTemps.push_back(MTE);
+ }
return MTE;
}
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index bb311e38409280..6df412cbb09c83 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -5481,10 +5481,7 @@ void Sema::InstantiateVariableInitializer(
EnterExpressionEvaluationContext Evaluated(
*this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated, Var);
- currentEvaluationContext().InLifetimeExtendingContext =
- parentEvaluationContext().InLifetimeExtendingContext;
- currentEvaluationContext().RebuildDefaultArgOrDefaultInit =
- parentEvaluationContext().RebuildDefaultArgOrDefaultInit;
+ keepInLifetimeExtendingContext();
// Instantiate the initializer.
ExprResult Init;
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index 4bbc024587915c..0daf620b4123e4 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -4254,10 +4254,7 @@ ExprResult TreeTransform<Derived>::TransformInitializer(Expr *Init,
getSema(), EnterExpressionEvaluationContext::InitList,
Construct->isListInitialization());
- getSema().currentEvaluationContext().InLifetimeExtendingContext =
- getSema().parentEvaluationContext().InLifetimeExtendingContext;
- getSema().currentEvaluationContext().RebuildDefaultArgOrDefaultInit =
- getSema().parentEvaluationContext().RebuildDefaultArgOrDefaultInit;
+ getSema().keepInLifetimeExtendingContext();
SmallVector<Expr*, 8> NewArgs;
bool ArgChanged = false;
if (getDerived().TransformExprs(Construct->getArgs(), Construct->getNumArgs(),
@@ -8927,9 +8924,8 @@ TreeTransform<Derived>::TransformCXXForRangeStmt(CXXForRangeStmt *S) {
// P2718R0 - Lifetime extension in range-based for loops.
if (getSema().getLangOpts().CPlusPlus23) {
- auto &LastRecord = getSema().currentEvaluationContext();
+ auto &LastRecord = getSema().ExprEvalContexts.back();
LastRecord.InLifetimeExtendingContext = true;
- LastRecord.RebuildDefaultArgOrDefaultInit = true;
}
StmtResult Init =
S->getInit() ? getDerived().TransformStmt(S->getInit()) : StmtResult();
@@ -14447,13 +14443,6 @@ 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() &&
@@ -14465,9 +14454,12 @@ 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(), E->isListInitialization());
+ T, LParenLoc, Args, E->getEndLoc(),
+ /*ListInitialization=*/LParenLoc.isInvalid());
}
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 f4949a9c9eedf4..1058b4e3ea4d93 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": "VarDecl",
-// CHECK-NEXT: "name": "b",
+// CHECK-NEXT: "kind": "FieldDecl",
+// CHECK-NEXT: "name": "a",
// CHECK-NEXT: "type": {
-// CHECK-NEXT: "qualType": "B"
+// CHECK-NEXT: "qualType": "const A &"
// 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 26864fbf15424d..15b29f04bf21bf 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 Var 0x{{[^ ]*}} 'b' 'B'
+// CHECK-NEXT: `-MaterializeTemporaryExpr 0x{{[^ ]*}} <{{.*}}> 'const A' lvalue extended by Field 0x{{[^ ]*}} 'a' 'const A &'
// 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 4458ad294af7cb..4e98bd4b0403eb 100644
--- a/clang/test/Analysis/lifetime-extended-regions.cpp
+++ b/clang/test/Analysis/lifetime-extended-regions.cpp
@@ -120,11 +120,10 @@ 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]+}}} }}
-
- // 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 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`
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 95e241f0d03e9b..cf6b45ceabf2cc 100644
--- a/clang/test/CXX/drs/cwg16xx.cpp
+++ b/clang/test/CXX/drs/cwg16xx.cpp
@@ -449,27 +449,6 @@ namespace cwg1696 { // cwg1696: 7
// since-cxx14-note at -2 {{default member initializer declared here}}
};
A a{a, a};
-
- struct A1 {
- A1() : v(42) {}
- // since-cxx14-error at -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 at -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 at -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
}
@@ -504,6 +483,8 @@ namespace cwg1696 { // cwg1696: 7
const A &a = A(); // #cwg1696-D1-a
};
D1 d1 = {}; // #cwg1696-d1
+ // since-cxx14-warning at -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 7f0fb8cf589d48..61b7faa96a9fbb 100644
--- a/clang/test/CXX/drs/cwg18xx.cpp
+++ b/clang/test/CXX/drs/cwg18xx.cpp
@@ -206,28 +206,19 @@ namespace cwg1814 { // cwg1814: yes
#endif
}
-namespace cwg1815 { // cwg1815: 20
+namespace cwg1815 { // cwg1815: no
#if __cplusplus >= 201402L
- struct A { int &&r = 0; };
+ // FIXME: needs codegen test
+ struct A { int &&r = 0; }; // #cwg1815-A
A a = {};
+ // since-cxx14-warning at -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 at -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 a6d2adfd1fd2c5..5554363cc69abb 100644
--- a/clang/test/CXX/special/class.temporary/p6.cpp
+++ b/clang/test/CXX/special/class.temporary/p6.cpp
@@ -269,40 +269,6 @@ 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/constexpr-default-arg.cpp b/clang/test/SemaCXX/constexpr-default-arg.cpp
index 901123bfb359ff..ec9b2927880bdf 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; };
+struct A { int &&r = 0; }; // expected-note 2{{default member initializer}}
struct B { A x, y; };
-B b = {}; // expected-no-diagnostics
+B b = {}; // expected-warning 2{{lifetime extension of temporary created by aggregate initialization using a default member initializer is not yet supported}}
}
diff --git a/clang/test/SemaCXX/cxx11-default-member-initializers.cpp b/clang/test/SemaCXX/cxx11-default-member-initializers.cpp
index b3f3eb508446b6..dd8e9c6b7fc11f 100644
--- a/clang/test/SemaCXX/cxx11-default-member-initializers.cpp
+++ b/clang/test/SemaCXX/cxx11-default-member-initializers.cpp
@@ -27,99 +27,6 @@ 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
-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 {
- // Test CXXDefaultInitExpr rebuild issue in
- // https://github.com/llvm/llvm-project/pull/87933
- 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
-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 21e05f19be0caa..0865dafe4bf92a 100644
--- a/clang/test/SemaCXX/eval-crashes.cpp
+++ b/clang/test/SemaCXX/eval-crashes.cpp
@@ -25,9 +25,11 @@ namespace pr33140_0b {
}
namespace pr33140_2 {
- struct A { int &&r = 0; };
+ // 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 B { A x, y; };
- B b = {};
+ B b = {}; // expected-warning 2{{lifetime extension of temporary created by aggregate initialization using a default member initializer is not yet supported}}
}
namespace pr33140_3 {
diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html
index f036fc5add2413..b638f0ff30bcce 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="unreleased" align="center">Clang 20</td>
+ <td class="none" align="center">No</td>
</tr>
<tr id="1816">
<td><a href="https://cplusplus.github.io/CWG/issues/1816.html">1816</a></td>
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