[clang] 96eced6 - [Clang] Implement CWG2369 "Ordering between constraints and substitution" (#102857)
via cfe-commits
cfe-commits at lists.llvm.org
Sat Jan 4 18:50:56 PST 2025
Author: Younan Zhang
Date: 2025-01-05T10:50:52+08:00
New Revision: 96eced624e0f120155256033fdcb8342e7e58d6e
URL: https://github.com/llvm/llvm-project/commit/96eced624e0f120155256033fdcb8342e7e58d6e
DIFF: https://github.com/llvm/llvm-project/commit/96eced624e0f120155256033fdcb8342e7e58d6e.diff
LOG: [Clang] Implement CWG2369 "Ordering between constraints and substitution" (#102857)
This patch partially implements CWG2369 for non-lambda-constrained
functions.
Lambdas are left intact at this point because we need extra work to
correctly instantiate captures before the function instantiation.
As a premise of CWG2369, this patch also implements CWG2770 to ensure
the function parameters are instantiated on demand.
Closes https://github.com/llvm/llvm-project/issues/54440
Added:
Modified:
clang/include/clang/Sema/Sema.h
clang/include/clang/Sema/Template.h
clang/lib/Sema/SemaConcept.cpp
clang/lib/Sema/SemaTemplateDeduction.cpp
clang/lib/Sema/SemaTemplateDeductionGuide.cpp
clang/lib/Sema/SemaTemplateInstantiate.cpp
clang/lib/Sema/TreeTransform.h
clang/test/CXX/drs/cwg23xx.cpp
clang/test/CXX/drs/cwg26xx.cpp
clang/test/CXX/drs/cwg27xx.cpp
clang/test/CXX/expr/expr.prim/expr.prim.req/nested-requirement.cpp
clang/test/CXX/temp/temp.constr/temp.constr.atomic/constrant-satisfaction-conversions.cpp
clang/test/SemaCXX/concept-crash-on-diagnostic.cpp
clang/test/SemaCXX/cxx20-ctad-type-alias.cpp
clang/test/SemaCXX/cxx23-assume.cpp
clang/test/SemaCXX/cxx2c-fold-exprs.cpp
clang/test/SemaCXX/lambda-unevaluated.cpp
clang/test/SemaTemplate/concepts-recursive-inst.cpp
clang/test/SemaTemplate/cxx2a-constraint-exprs.cpp
clang/test/SemaTemplate/deduction-guide.cpp
clang/test/SemaTemplate/nested-implicit-deduction-guides.cpp
clang/www/cxx_dr_status.html
Removed:
################################################################################
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 5ee7ea48cc983c..af59b7f38c71aa 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -13055,6 +13055,7 @@ class Sema final : public SemaBase {
///
/// \param SkipForSpecialization when specified, any template specializations
/// in a traversal would be ignored.
+ ///
/// \param ForDefaultArgumentSubstitution indicates we should continue looking
/// when encountering a specialized member function template, rather than
/// returning immediately.
@@ -13066,6 +13067,17 @@ class Sema final : public SemaBase {
bool SkipForSpecialization = false,
bool ForDefaultArgumentSubstitution = false);
+ /// Apart from storing the result to \p Result, this behaves the same as
+ /// another overload.
+ void getTemplateInstantiationArgs(
+ MultiLevelTemplateArgumentList &Result, const NamedDecl *D,
+ const DeclContext *DC = nullptr, bool Final = false,
+ std::optional<ArrayRef<TemplateArgument>> Innermost = std::nullopt,
+ bool RelativeToPrimary = false, const FunctionDecl *Pattern = nullptr,
+ bool ForConstraintInstantiation = false,
+ bool SkipForSpecialization = false,
+ bool ForDefaultArgumentSubstitution = false);
+
/// RAII object to handle the state changes required to synthesize
/// a function body.
class SynthesizedFunctionScope {
@@ -13335,7 +13347,7 @@ class Sema final : public SemaBase {
ExprResult
SubstConstraintExpr(Expr *E,
const MultiLevelTemplateArgumentList &TemplateArgs);
- // Unlike the above, this does not evaluates constraints.
+ // Unlike the above, this does not evaluate constraints.
ExprResult SubstConstraintExprWithoutSatisfaction(
Expr *E, const MultiLevelTemplateArgumentList &TemplateArgs);
@@ -14456,10 +14468,10 @@ class Sema final : public SemaBase {
const MultiLevelTemplateArgumentList &TemplateArgs,
SourceRange TemplateIDRange);
- bool CheckInstantiatedFunctionTemplateConstraints(
- SourceLocation PointOfInstantiation, FunctionDecl *Decl,
- ArrayRef<TemplateArgument> TemplateArgs,
- ConstraintSatisfaction &Satisfaction);
+ bool CheckFunctionTemplateConstraints(SourceLocation PointOfInstantiation,
+ FunctionDecl *Decl,
+ ArrayRef<TemplateArgument> TemplateArgs,
+ ConstraintSatisfaction &Satisfaction);
/// \brief Emit diagnostics explaining why a constraint expression was deemed
/// unsatisfied.
diff --git a/clang/include/clang/Sema/Template.h b/clang/include/clang/Sema/Template.h
index 9800f75f676aaf..59a0575ca98036 100644
--- a/clang/include/clang/Sema/Template.h
+++ b/clang/include/clang/Sema/Template.h
@@ -522,6 +522,12 @@ enum class TemplateSubstitutionKind : char {
llvm::PointerUnion<Decl *, DeclArgumentPack *> *
findInstantiationOf(const Decl *D);
+ /// Similar to \p findInstantiationOf(), but it wouldn't assert if the
+ /// instantiation was not found within the current instantiation scope. This
+ /// is helpful for on-demand declaration instantiation.
+ llvm::PointerUnion<Decl *, DeclArgumentPack *> *
+ findInstantiationUnsafe(const Decl *D);
+
void InstantiatedLocal(const Decl *D, Decl *Inst);
void InstantiatedLocalPackArg(const Decl *D, VarDecl *Inst);
void MakeInstantiatedLocalArgPack(const Decl *D);
diff --git a/clang/lib/Sema/SemaConcept.cpp b/clang/lib/Sema/SemaConcept.cpp
index 539de00bd104f5..10f4920a761f3c 100644
--- a/clang/lib/Sema/SemaConcept.cpp
+++ b/clang/lib/Sema/SemaConcept.cpp
@@ -846,7 +846,7 @@ bool Sema::CheckFunctionConstraints(const FunctionDecl *FD,
bool ForOverloadResolution) {
// Don't check constraints if the function is dependent. Also don't check if
// this is a function template specialization, as the call to
- // CheckinstantiatedFunctionTemplateConstraints after this will check it
+ // CheckFunctionTemplateConstraints after this will check it
// better.
if (FD->isDependentContext() ||
FD->getTemplatedKind() ==
@@ -1111,12 +1111,55 @@ bool Sema::EnsureTemplateArgumentListConstraints(
return false;
}
-bool Sema::CheckInstantiatedFunctionTemplateConstraints(
+static bool CheckFunctionConstraintsWithoutInstantiation(
+ Sema &SemaRef, SourceLocation PointOfInstantiation,
+ FunctionTemplateDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
+ ConstraintSatisfaction &Satisfaction) {
+ SmallVector<const Expr *, 3> TemplateAC;
+ Template->getAssociatedConstraints(TemplateAC);
+ if (TemplateAC.empty()) {
+ Satisfaction.IsSatisfied = true;
+ return false;
+ }
+
+ LocalInstantiationScope Scope(SemaRef);
+
+ FunctionDecl *FD = Template->getTemplatedDecl();
+ // Collect the list of template arguments relative to the 'primary'
+ // template. We need the entire list, since the constraint is completely
+ // uninstantiated at this point.
+
+ // FIXME: Add TemplateArgs through the 'Innermost' parameter once
+ // the refactoring of getTemplateInstantiationArgs() relands.
+ MultiLevelTemplateArgumentList MLTAL;
+ MLTAL.addOuterTemplateArguments(Template, std::nullopt, /*Final=*/false);
+ SemaRef.getTemplateInstantiationArgs(
+ MLTAL, /*D=*/FD, FD,
+ /*Final=*/false, /*Innermost=*/std::nullopt, /*RelativeToPrimary=*/true,
+ /*Pattern=*/nullptr, /*ForConstraintInstantiation=*/true);
+ MLTAL.replaceInnermostTemplateArguments(Template, TemplateArgs);
+
+ Sema::ContextRAII SavedContext(SemaRef, FD);
+ std::optional<Sema::CXXThisScopeRAII> ThisScope;
+ if (auto *Method = dyn_cast<CXXMethodDecl>(FD))
+ ThisScope.emplace(SemaRef, /*Record=*/Method->getParent(),
+ /*ThisQuals=*/Method->getMethodQualifiers());
+ return SemaRef.CheckConstraintSatisfaction(
+ Template, TemplateAC, MLTAL, PointOfInstantiation, Satisfaction);
+}
+
+bool Sema::CheckFunctionTemplateConstraints(
SourceLocation PointOfInstantiation, FunctionDecl *Decl,
ArrayRef<TemplateArgument> TemplateArgs,
ConstraintSatisfaction &Satisfaction) {
// In most cases we're not going to have constraints, so check for that first.
FunctionTemplateDecl *Template = Decl->getPrimaryTemplate();
+
+ if (!Template)
+ return ::CheckFunctionConstraintsWithoutInstantiation(
+ *this, PointOfInstantiation, Decl->getDescribedFunctionTemplate(),
+ TemplateArgs, Satisfaction);
+
// Note - code synthesis context for the constraints check is created
// inside CheckConstraintsSatisfaction.
SmallVector<const Expr *, 3> TemplateAC;
diff --git a/clang/lib/Sema/SemaTemplateDeduction.cpp b/clang/lib/Sema/SemaTemplateDeduction.cpp
index 1c1f6e30ab7b83..acd1151184e42f 100644
--- a/clang/lib/Sema/SemaTemplateDeduction.cpp
+++ b/clang/lib/Sema/SemaTemplateDeduction.cpp
@@ -3936,18 +3936,6 @@ TemplateDeductionResult Sema::FinishTemplateArgumentDeduction(
Result != TemplateDeductionResult::Success)
return Result;
- // C++ [temp.deduct.call]p10: [DR1391]
- // If deduction succeeds for all parameters that contain
- // template-parameters that participate in template argument deduction,
- // and all template arguments are explicitly specified, deduced, or
- // obtained from default template arguments, remaining parameters are then
- // compared with the corresponding arguments. For each remaining parameter
- // P with a type that was non-dependent before substitution of any
- // explicitly-specified template arguments, if the corresponding argument
- // A cannot be implicitly converted to P, deduction fails.
- if (CheckNonDependent())
- return TemplateDeductionResult::NonDependentConversionFailure;
-
// Form the template argument list from the deduced template arguments.
TemplateArgumentList *SugaredDeducedArgumentList =
TemplateArgumentList::CreateCopy(Context, SugaredBuilder);
@@ -3977,6 +3965,39 @@ TemplateDeductionResult Sema::FinishTemplateArgumentDeduction(
FD = const_cast<FunctionDecl *>(FDFriend);
Owner = FD->getLexicalDeclContext();
}
+ // C++20 [temp.deduct.general]p5: [CWG2369]
+ // If the function template has associated constraints, those constraints
+ // are checked for satisfaction. If the constraints are not satisfied, type
+ // deduction fails.
+ //
+ // FIXME: We haven't implemented CWG2369 for lambdas yet, because we need
+ // to figure out how to instantiate lambda captures to the scope without
+ // first instantiating the lambda.
+ bool IsLambda = isLambdaCallOperator(FD) || isLambdaConversionOperator(FD);
+ if (!IsLambda && !IsIncomplete) {
+ if (CheckFunctionTemplateConstraints(
+ Info.getLocation(),
+ FunctionTemplate->getCanonicalDecl()->getTemplatedDecl(),
+ CanonicalBuilder, Info.AssociatedConstraintsSatisfaction))
+ return TemplateDeductionResult::MiscellaneousDeductionFailure;
+ if (!Info.AssociatedConstraintsSatisfaction.IsSatisfied) {
+ Info.reset(Info.takeSugared(),
+ TemplateArgumentList::CreateCopy(Context, CanonicalBuilder));
+ return TemplateDeductionResult::ConstraintsNotSatisfied;
+ }
+ }
+ // C++ [temp.deduct.call]p10: [CWG1391]
+ // If deduction succeeds for all parameters that contain
+ // template-parameters that participate in template argument deduction,
+ // and all template arguments are explicitly specified, deduced, or
+ // obtained from default template arguments, remaining parameters are then
+ // compared with the corresponding arguments. For each remaining parameter
+ // P with a type that was non-dependent before substitution of any
+ // explicitly-specified template arguments, if the corresponding argument
+ // A cannot be implicitly converted to P, deduction fails.
+ if (CheckNonDependent())
+ return TemplateDeductionResult::NonDependentConversionFailure;
+
MultiLevelTemplateArgumentList SubstArgs(
FunctionTemplate, CanonicalDeducedArgumentList->asArray(),
/*Final=*/false);
@@ -4011,8 +4032,8 @@ TemplateDeductionResult Sema::FinishTemplateArgumentDeduction(
// ([temp.constr.decl]), those constraints are checked for satisfaction
// ([temp.constr.constr]). If the constraints are not satisfied, type
// deduction fails.
- if (!IsIncomplete) {
- if (CheckInstantiatedFunctionTemplateConstraints(
+ if (IsLambda && !IsIncomplete) {
+ if (CheckFunctionTemplateConstraints(
Info.getLocation(), Specialization, CanonicalBuilder,
Info.AssociatedConstraintsSatisfaction))
return TemplateDeductionResult::MiscellaneousDeductionFailure;
diff --git a/clang/lib/Sema/SemaTemplateDeductionGuide.cpp b/clang/lib/Sema/SemaTemplateDeductionGuide.cpp
index d42c3765aa534f..5d6c11a75303df 100644
--- a/clang/lib/Sema/SemaTemplateDeductionGuide.cpp
+++ b/clang/lib/Sema/SemaTemplateDeductionGuide.cpp
@@ -902,10 +902,12 @@ Expr *buildIsDeducibleConstraint(Sema &SemaRef,
Context.getTrivialTypeSourceInfo(
Context.getDeducedTemplateSpecializationType(
TemplateName(AliasTemplate), /*DeducedType=*/QualType(),
- /*IsDependent=*/true)), // template specialization type whose
- // arguments will be deduced.
+ /*IsDependent=*/true),
+ AliasTemplate->getLocation()), // template specialization type whose
+ // arguments will be deduced.
Context.getTrivialTypeSourceInfo(
- ReturnType), // type from which template arguments are deduced.
+ ReturnType, AliasTemplate->getLocation()), // type from which template
+ // arguments are deduced.
};
return TypeTraitExpr::Create(
Context, Context.getLogicalOperationType(), AliasTemplate->getLocation(),
diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index fb0f38df62a744..cab9ae79ce5cb0 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -475,6 +475,21 @@ MultiLevelTemplateArgumentList Sema::getTemplateInstantiationArgs(
assert((ND || DC) && "Can't find arguments for a decl if one isn't provided");
// Accumulate the set of template argument lists in this structure.
MultiLevelTemplateArgumentList Result;
+ getTemplateInstantiationArgs(
+ Result, ND, DC, Final, Innermost, RelativeToPrimary, Pattern,
+ ForConstraintInstantiation, SkipForSpecialization,
+ ForDefaultArgumentSubstitution);
+ return Result;
+}
+
+void Sema::getTemplateInstantiationArgs(
+ MultiLevelTemplateArgumentList &Result, const NamedDecl *ND,
+ const DeclContext *DC, bool Final,
+ std::optional<ArrayRef<TemplateArgument>> Innermost, bool RelativeToPrimary,
+ const FunctionDecl *Pattern, bool ForConstraintInstantiation,
+ bool SkipForSpecialization, bool ForDefaultArgumentSubstitution) {
+ assert((ND || DC) && "Can't find arguments for a decl if one isn't provided");
+ // Accumulate the set of template argument lists in this structure.
using namespace TemplateInstArgsHelpers;
const Decl *CurDecl = ND;
@@ -535,14 +550,12 @@ MultiLevelTemplateArgumentList Sema::getTemplateInstantiationArgs(
}
if (R.IsDone)
- return Result;
+ return;
if (R.ClearRelativeToPrimary)
RelativeToPrimary = false;
assert(R.NextDecl);
CurDecl = R.NextDecl;
}
-
- return Result;
}
bool Sema::CodeSynthesisContext::isInstantiationRecord() const {
@@ -1349,6 +1362,19 @@ namespace {
// Whether an incomplete substituion should be treated as an error.
bool BailOutOnIncomplete;
+ private:
+ bool isSubstitutingConstraints() const {
+ return llvm::any_of(SemaRef.CodeSynthesisContexts, [](auto &Context) {
+ return Context.Kind ==
+ Sema::CodeSynthesisContext::ConstraintSubstitution;
+ });
+ }
+
+ // CWG2770: Function parameters should be instantiated when they are
+ // needed by a satisfaction check of an atomic constraint or
+ // (recursively) by another function parameter.
+ bool maybeInstantiateFunctionParameterToScope(ParmVarDecl *OldParm);
+
public:
typedef TreeTransform<TemplateInstantiator> inherited;
@@ -1405,12 +1431,19 @@ namespace {
ArrayRef<UnexpandedParameterPack> Unexpanded,
bool &ShouldExpand, bool &RetainExpansion,
std::optional<unsigned> &NumExpansions) {
- return getSema().CheckParameterPacksForExpansion(EllipsisLoc,
- PatternRange, Unexpanded,
- TemplateArgs,
- ShouldExpand,
- RetainExpansion,
- NumExpansions);
+ if (SemaRef.CurrentInstantiationScope && isSubstitutingConstraints()) {
+ for (UnexpandedParameterPack ParmPack : Unexpanded) {
+ NamedDecl *VD = ParmPack.first.dyn_cast<NamedDecl *>();
+ if (!isa_and_present<ParmVarDecl>(VD))
+ continue;
+ if (maybeInstantiateFunctionParameterToScope(cast<ParmVarDecl>(VD)))
+ return true;
+ }
+ }
+
+ return getSema().CheckParameterPacksForExpansion(
+ EllipsisLoc, PatternRange, Unexpanded, TemplateArgs, ShouldExpand,
+ RetainExpansion, NumExpansions);
}
void ExpandingFunctionParameterPack(ParmVarDecl *Pack) {
@@ -1911,9 +1944,62 @@ Decl *TemplateInstantiator::TransformDecl(SourceLocation Loc, Decl *D) {
// template parameter.
}
+ if (SemaRef.CurrentInstantiationScope) {
+ if (isSubstitutingConstraints() && isa<ParmVarDecl>(D) &&
+ maybeInstantiateFunctionParameterToScope(cast<ParmVarDecl>(D)))
+ return nullptr;
+ }
+
return SemaRef.FindInstantiatedDecl(Loc, cast<NamedDecl>(D), TemplateArgs);
}
+bool TemplateInstantiator::maybeInstantiateFunctionParameterToScope(
+ ParmVarDecl *OldParm) {
+ if (SemaRef.CurrentInstantiationScope->findInstantiationUnsafe(OldParm))
+ return false;
+ // We're instantiating a function parameter whose associated function template
+ // has not been instantiated at this point for constraint evaluation, so make
+ // sure the instantiated parameters are owned by a function declaration such
+ // that they can be correctly 'captured' in tryCaptureVariable().
+ Sema::ContextRAII Context(SemaRef, OldParm->getDeclContext());
+
+ if (!OldParm->isParameterPack())
+ return !TransformFunctionTypeParam(OldParm, /*indexAdjustment=*/0,
+ /*NumExpansions=*/std::nullopt,
+ /*ExpectParameterPack=*/false);
+
+ SmallVector<UnexpandedParameterPack, 2> Unexpanded;
+
+ // Find the parameter packs that could be expanded.
+ TypeLoc TL = OldParm->getTypeSourceInfo()->getTypeLoc();
+ PackExpansionTypeLoc ExpansionTL = TL.castAs<PackExpansionTypeLoc>();
+ TypeLoc Pattern = ExpansionTL.getPatternLoc();
+ SemaRef.collectUnexpandedParameterPacks(Pattern, Unexpanded);
+ assert(!Unexpanded.empty() && "Pack expansion without parameter packs?");
+
+ bool ShouldExpand = false;
+ bool RetainExpansion = false;
+ std::optional<unsigned> OrigNumExpansions =
+ ExpansionTL.getTypePtr()->getNumExpansions();
+ std::optional<unsigned> NumExpansions = OrigNumExpansions;
+ if (TryExpandParameterPacks(ExpansionTL.getEllipsisLoc(),
+ Pattern.getSourceRange(), Unexpanded,
+ ShouldExpand, RetainExpansion, NumExpansions))
+ return true;
+
+ assert(ShouldExpand && !RetainExpansion &&
+ "Shouldn't preserve pack expansion when evaluating constraints");
+ ExpandingFunctionParameterPack(OldParm);
+ for (unsigned I = 0; I != *NumExpansions; ++I) {
+ Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(getSema(), I);
+ if (!TransformFunctionTypeParam(OldParm, /*indexAdjustment=*/0,
+ /*NumExpansions=*/OrigNumExpansions,
+ /*ExpectParameterPack=*/false))
+ return true;
+ }
+ return false;
+}
+
Decl *TemplateInstantiator::TransformDefinition(SourceLocation Loc, Decl *D) {
Decl *Inst = getSema().SubstDecl(D, getSema().CurContext, TemplateArgs);
if (!Inst)
@@ -4591,9 +4677,8 @@ static const Decl *getCanonicalParmVarDecl(const Decl *D) {
return D;
}
-
llvm::PointerUnion<Decl *, LocalInstantiationScope::DeclArgumentPack *> *
-LocalInstantiationScope::findInstantiationOf(const Decl *D) {
+LocalInstantiationScope::findInstantiationUnsafe(const Decl *D) {
D = getCanonicalParmVarDecl(D);
for (LocalInstantiationScope *Current = this; Current;
Current = Current->Outer) {
@@ -4618,6 +4703,14 @@ LocalInstantiationScope::findInstantiationOf(const Decl *D) {
break;
}
+ return nullptr;
+}
+
+llvm::PointerUnion<Decl *, LocalInstantiationScope::DeclArgumentPack *> *
+LocalInstantiationScope::findInstantiationOf(const Decl *D) {
+ auto *Result = findInstantiationUnsafe(D);
+ if (Result)
+ return Result;
// If we're performing a partial substitution during template argument
// deduction, we may not have values for template parameters yet.
if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index 5d43d98ce49e46..0121be81bc6acd 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -713,7 +713,7 @@ class TreeTransform {
/// variables vector are acceptable.
///
/// LastParamTransformed, if non-null, will be set to the index of the last
- /// parameter on which transfromation was started. In the event of an error,
+ /// parameter on which transformation was started. In the event of an error,
/// this will contain the parameter which failed to instantiate.
///
/// Return true on error.
diff --git a/clang/test/CXX/drs/cwg23xx.cpp b/clang/test/CXX/drs/cwg23xx.cpp
index 7f57d237526bc5..f4992c1426844a 100644
--- a/clang/test/CXX/drs/cwg23xx.cpp
+++ b/clang/test/CXX/drs/cwg23xx.cpp
@@ -528,3 +528,35 @@ namespace cwg2397 { // cwg2397: 17
} // namespace cwg2397
#endif
+
+#if __cplusplus >= 202002L
+
+namespace cwg2369 { // cwg2369: partial
+
+template <class T> struct Z {
+ typedef typename T::x xx;
+};
+
+template <class T>
+concept C = requires { typename T::A; };
+template <C T> typename Z<T>::xx f(void *, T); // #1
+template <class T> void f(int, T); // #2
+
+struct A {
+} a;
+
+struct ZZ {
+ template <class T, class = typename Z<T>::xx> operator T *();
+ operator int();
+};
+
+void foo() {
+ ZZ zz;
+ f(1, a); // OK, deduction fails for #1 because there is no conversion from int
+ // to void*
+ f(zz, 42); // OK, deduction fails for #1 because C<int> is not satisfied
+}
+
+} // namespace cwg2369
+
+#endif
diff --git a/clang/test/CXX/drs/cwg26xx.cpp b/clang/test/CXX/drs/cwg26xx.cpp
index 63a954c803b77a..35814ca9a26a39 100644
--- a/clang/test/CXX/drs/cwg26xx.cpp
+++ b/clang/test/CXX/drs/cwg26xx.cpp
@@ -319,7 +319,7 @@ void f(T) requires requires { []() { T::invalid; } (); };
// since-cxx20-note at -3 {{in instantiation of requirement here}}
// since-cxx20-note at -4 {{while substituting template arguments into constraint expression here}}
// since-cxx20-note@#cwg2672-f-0 {{while checking constraint satisfaction for template 'f<int>' required here}}
-// since-cxx20-note@#cwg2672-f-0 {{in instantiation of function template specialization 'cwg2672::f<int>' requested here}}
+// since-cxx20-note@#cwg2672-f-0 {{while substituting deduced template arguments into function template 'f' [with T = int]}}
void f(...);
template <class T>
diff --git a/clang/test/CXX/drs/cwg27xx.cpp b/clang/test/CXX/drs/cwg27xx.cpp
index fb5c8b1d1fbf8b..b0adf5690acc64 100644
--- a/clang/test/CXX/drs/cwg27xx.cpp
+++ b/clang/test/CXX/drs/cwg27xx.cpp
@@ -174,6 +174,26 @@ static_assert(!__is_layout_compatible(StructWithAnonUnion, StructWithAnonUnion3)
#endif
} // namespace cwg2759
+#if __cplusplus >= 202002L
+namespace cwg2770 { // cwg2770: 20
+template<typename T>
+struct B {
+ static_assert(sizeof(T) == 1);
+ using type = int;
+};
+
+template<typename T>
+int f(T t, typename B<T>::type u) requires (sizeof(t) == 1);
+
+template<typename T>
+int f(T t, long);
+
+int i = f(1, 2);
+int j = f('a', 2);
+
+} // namespace cwg2770
+#endif
+
namespace cwg2789 { // cwg2789: 18
#if __cplusplus >= 202302L
template <typename T = int>
diff --git a/clang/test/CXX/expr/expr.prim/expr.prim.req/nested-requirement.cpp b/clang/test/CXX/expr/expr.prim/expr.prim.req/nested-requirement.cpp
index 763d983d20f615..a23f7dc595171e 100644
--- a/clang/test/CXX/expr/expr.prim/expr.prim.req/nested-requirement.cpp
+++ b/clang/test/CXX/expr/expr.prim/expr.prim.req/nested-requirement.cpp
@@ -154,7 +154,7 @@ void func() {
bar<int>();
// expected-note at -1 {{while checking constraint satisfaction for template 'bar<int>' required here}} \
- // expected-note at -1 {{in instantiation of function template specialization}}
+ // expected-note at -1 {{while substituting deduced template arguments into function template 'bar' [with T = int]}}
// expected-note@#bar {{in instantiation of static data member}}
// expected-note@#bar {{in instantiation of requirement here}}
// expected-note@#bar {{while checking the satisfaction of nested requirement requested here}}
diff --git a/clang/test/CXX/temp/temp.constr/temp.constr.atomic/constrant-satisfaction-conversions.cpp b/clang/test/CXX/temp/temp.constr/temp.constr.atomic/constrant-satisfaction-conversions.cpp
index ba8e2dc372e984..c41de77986bcae 100644
--- a/clang/test/CXX/temp/temp.constr/temp.constr.atomic/constrant-satisfaction-conversions.cpp
+++ b/clang/test/CXX/temp/temp.constr/temp.constr.atomic/constrant-satisfaction-conversions.cpp
@@ -11,7 +11,7 @@ template<typename T> struct S {
// expected-error at +3{{atomic constraint must be of type 'bool' (found 'S<int>')}}
// expected-note@#FINST{{while checking constraint satisfaction}}
-// expected-note@#FINST{{in instantiation of function template specialization}}
+// expected-note@#FINST{{while substituting deduced template arguments into function template 'f' [with T = int]}}
template<typename T> requires (S<T>{})
void f(T);
void f(int);
@@ -19,7 +19,7 @@ void f(int);
// Ensure this applies to operator && as well.
// expected-error at +3{{atomic constraint must be of type 'bool' (found 'S<int>')}}
// expected-note@#F2INST{{while checking constraint satisfaction}}
-// expected-note@#F2INST{{in instantiation of function template specialization}}
+// expected-note@#F2INST{{while substituting deduced template arguments into function template 'f2' [with T = int]}}
template<typename T> requires (S<T>{} && true)
void f2(T);
void f2(int);
@@ -32,7 +32,7 @@ template<typename T> requires requires {
// expected-note at -4{{while checking the satisfaction}}
// expected-note at -6{{while substituting template arguments}}
// expected-note@#F3INST{{while checking constraint satisfaction}}
- // expected-note@#F3INST{{in instantiation of function template specialization}}
+ // expected-note@#F3INST{{while substituting deduced template arguments into function template 'f3' [with T = int]}}
//
}
void f3(T);
diff --git a/clang/test/SemaCXX/concept-crash-on-diagnostic.cpp b/clang/test/SemaCXX/concept-crash-on-diagnostic.cpp
index 71e55c8290ee4a..ccc109cbca0f19 100644
--- a/clang/test/SemaCXX/concept-crash-on-diagnostic.cpp
+++ b/clang/test/SemaCXX/concept-crash-on-diagnostic.cpp
@@ -31,7 +31,7 @@ void function() {
// expected-note@#3 {{checking the satisfaction of concept 'convertible_to<bool, bool>'}}
// expected-note@#2 {{substituting template arguments into constraint expression here}}
// expected-note@#5 {{checking constraint satisfaction for template 'compare<Object *, Object *>'}}
-// expected-note@#5 {{in instantiation of function template specialization 'compare<Object *, Object *>' requested here}}
+// expected-note@#5 {{while substituting deduced template arguments into function template 'compare' [with IteratorL = Object *, IteratorR = Object *]}}
// expected-note@#4 {{candidate template ignored: constraints not satisfied [with IteratorL = Object *, IteratorR = Object *]}}
// We don't know exactly the substituted type for `lhs == rhs`, thus a placeholder 'expr-type' is emitted.
diff --git a/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp b/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp
index 2d43e46b9e3d76..23c898e6379b05 100644
--- a/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp
+++ b/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp
@@ -196,7 +196,7 @@ struct Foo {
template <int K>
using Bar = Foo<double, K>; // expected-note {{constraints not satisfied for class template 'Foo'}}
-// expected-note at -1 {{candidate template ignored: could not match}}
+// expected-note at -1 {{candidate template ignored: could not match}} expected-note at -1 {{candidate template ignored: constraints not satisfied}}
// expected-note at -2 {{implicit deduction guide declared as 'template <int K> requires __is_deducible(test14::Bar, Foo<double, K>) Bar(Foo<double, K>) -> Foo<double, K>'}}
// expected-note at -3 {{implicit deduction guide declared as 'template <int K> requires __is_deducible(test14::Bar, Foo<double, K>) Bar(const double (&)[K]) -> Foo<double, K>'}}
double abc[3];
diff --git a/clang/test/SemaCXX/cxx23-assume.cpp b/clang/test/SemaCXX/cxx23-assume.cpp
index 7f80cdfe7d4523..726cb3bff652e7 100644
--- a/clang/test/SemaCXX/cxx23-assume.cpp
+++ b/clang/test/SemaCXX/cxx23-assume.cpp
@@ -129,12 +129,12 @@ constexpr int f5() requires (!C<T>) { return 2; } // expected-note 4 {{while che
static_assert(f5<int>() == 1);
static_assert(f5<D>() == 1); // expected-note 3 {{while checking constraint satisfaction}}
- // expected-note at -1 3 {{in instantiation of}}
+ // expected-note at -1 3 {{while substituting deduced template arguments}}
// expected-error at -2 {{no matching function for call}}
static_assert(f5<double>() == 2);
-static_assert(f5<E>() == 1); // expected-note {{while checking constraint satisfaction}} expected-note {{in instantiation of}}
-static_assert(f5<F>() == 2); // expected-note {{while checking constraint satisfaction}} expected-note {{in instantiation of}}
+static_assert(f5<E>() == 1); // expected-note {{while checking constraint satisfaction}} expected-note {{while substituting deduced template arguments}}
+static_assert(f5<F>() == 2); // expected-note {{while checking constraint satisfaction}} expected-note {{while substituting deduced template arguments}}
// Do not validate assumptions whose evaluation would have side-effects.
constexpr int foo() {
diff --git a/clang/test/SemaCXX/cxx2c-fold-exprs.cpp b/clang/test/SemaCXX/cxx2c-fold-exprs.cpp
index 48061439941f23..4220486d3aed30 100644
--- a/clang/test/SemaCXX/cxx2c-fold-exprs.cpp
+++ b/clang/test/SemaCXX/cxx2c-fold-exprs.cpp
@@ -233,7 +233,7 @@ void g() {
A<Thingy, Thingy> *ap;
f(ap, ap); // expected-error{{no matching function for call to 'f'}} \
// expected-note {{while checking constraint satisfaction}} \
- // expected-note {{in instantiation of function template specialization}}
+ // expected-note {{while substituting deduced template arguments}}
}
}
diff --git a/clang/test/SemaCXX/lambda-unevaluated.cpp b/clang/test/SemaCXX/lambda-unevaluated.cpp
index a9bcab58464e26..d3f937281f201a 100644
--- a/clang/test/SemaCXX/lambda-unevaluated.cpp
+++ b/clang/test/SemaCXX/lambda-unevaluated.cpp
@@ -174,7 +174,7 @@ int* func(T) requires requires { []() { T::foo(); }; }; // expected-error{{type
double* func(...);
static_assert(__is_same(decltype(func(0)), double*)); // expected-note {{while checking constraint satisfaction for template 'func<int>' required here}}
- // expected-note at -1 {{in instantiation of function template specialization 'lambda_in_constraints::func<int>'}}
+ // expected-note at -1 {{while substituting deduced template arguments into function template 'func' [with T = int]}}
static_assert(__is_same(decltype(func(WithFoo())), int*));
template <class T>
@@ -252,7 +252,7 @@ S s("a"); // #use
// expected-note@#S-requires {{substituting template arguments into constraint expression here}}
// expected-note@#S-requires {{in instantiation of requirement here}}
// expected-note@#use {{checking constraint satisfaction for template 'S<const char *>' required here}}
-// expected-note@#use {{requested here}}
+// expected-note@#use {{while substituting deduced template arguments into function template 'S' [with value:auto = const char *]}}
// expected-note-re@#S 2{{candidate constructor {{.*}} not viable}}
// expected-note@#S-ctor {{constraints not satisfied}}
// expected-note-re@#S-requires {{because {{.*}} would be invalid}}
diff --git a/clang/test/SemaTemplate/concepts-recursive-inst.cpp b/clang/test/SemaTemplate/concepts-recursive-inst.cpp
index 9330df8cdd0398..30a410cef91ee9 100644
--- a/clang/test/SemaTemplate/concepts-recursive-inst.cpp
+++ b/clang/test/SemaTemplate/concepts-recursive-inst.cpp
@@ -76,7 +76,7 @@ auto it = begin(rng); // #BEGIN_CALL
// expected-note@#INF_BEGIN {{while checking the satisfaction of concept 'Inf<DirectRecursiveCheck::my_range>' requested here}}
// expected-note@#INF_BEGIN {{while substituting template arguments into constraint expression here}}
// expected-note@#BEGIN_CALL {{while checking constraint satisfaction for template 'begin<DirectRecursiveCheck::my_range>' required here}}
-// expected-note@#BEGIN_CALL {{in instantiation of function template specialization}}
+// expected-note@#BEGIN_CALL {{while substituting deduced template arguments into function template}}
// Fallout of the failure is failed lookup, which is necessary to stop odd
// cascading errors.
@@ -103,7 +103,7 @@ namespace GH50891 {
// expected-note@#OP_TO {{while checking the satisfaction of concept 'Numeric<GH50891::Deferred>' requested here}}
// expected-note@#OP_TO {{while substituting template arguments into constraint expression here}}
// expected-note@#FOO_CALL {{while checking constraint satisfaction for template}}
- // expected-note@#FOO_CALL {{in instantiation of function template specialization}}
+ // expected-note@#FOO_CALL {{while substituting deduced template arguments into function template}}
// expected-note@#FOO_CALL {{in instantiation of requirement here}}
// expected-note@#NUMERIC {{while substituting template arguments into constraint expression here}}
diff --git a/clang/test/SemaTemplate/cxx2a-constraint-exprs.cpp b/clang/test/SemaTemplate/cxx2a-constraint-exprs.cpp
index f4403587a62594..5809ef684bbf3b 100644
--- a/clang/test/SemaTemplate/cxx2a-constraint-exprs.cpp
+++ b/clang/test/SemaTemplate/cxx2a-constraint-exprs.cpp
@@ -34,7 +34,7 @@ namespace constant_evaluated {
expected-note at -1{{candidate template ignored}}
int a = (foo<int>(), 0);
// expected-note at -1 {{while checking}} expected-error at -1{{no matching function}} \
- expected-note at -1 {{in instantiation}}
+ expected-note at -1 {{while substituting}}
template<typename T> void bar() requires requires { requires f<int[2]>; } { };
// expected-note at -1{{in instantiation}} \
expected-note at -1{{while substituting}} \
diff --git a/clang/test/SemaTemplate/deduction-guide.cpp b/clang/test/SemaTemplate/deduction-guide.cpp
index d03c783313dd71..67d00bb49f77d7 100644
--- a/clang/test/SemaTemplate/deduction-guide.cpp
+++ b/clang/test/SemaTemplate/deduction-guide.cpp
@@ -234,11 +234,6 @@ F s(0);
// CHECK: | `-CXXBoolLiteralExpr {{.*}} 'bool' false
// CHECK: |-CXXDeductionGuideDecl {{.*}} implicit <deduction guide for F> 'auto (U) -> F<>'
// CHECK: | `-ParmVarDecl {{.*}} 'U'
-// CHECK: `-CXXDeductionGuideDecl {{.*}} implicit <deduction guide for F> 'auto (int) -> F<>'
-// CHECK: |-TemplateArgument integral ''x''
-// CHECK: |-TemplateArgument type 'int'
-// CHECK: | `-BuiltinType {{.*}} 'int'
-// CHECK: `-ParmVarDecl {{.*}} 'int'
// CHECK: FunctionProtoType {{.*}} 'auto (U) -> F<>' dependent trailing_return cdecl
// CHECK: |-InjectedClassNameType {{.*}} 'F<>' dependent
// CHECK: | `-CXXRecord {{.*}} 'F'
diff --git a/clang/test/SemaTemplate/nested-implicit-deduction-guides.cpp b/clang/test/SemaTemplate/nested-implicit-deduction-guides.cpp
index af3e3358f61382..5c7a90273d0e0f 100644
--- a/clang/test/SemaTemplate/nested-implicit-deduction-guides.cpp
+++ b/clang/test/SemaTemplate/nested-implicit-deduction-guides.cpp
@@ -38,7 +38,7 @@ template<typename A, typename T>
concept True = true;
template<typename T>
-concept False = false;
+concept False = false; // #False
template<class X> struct concepts {
template<class Y> struct B {
@@ -68,7 +68,7 @@ template<typename X> struct nested_init_list {
Y y;
};
- template<False F>
+ template<False F> // #INIT_LIST_INNER_INVALID_HEADER
struct concept_fail { // #INIT_LIST_INNER_INVALID
X x;
F f;
@@ -81,7 +81,9 @@ using NIL = nested_init_list<int>::B<int>;
// expected-error at +1 {{no viable constructor or deduction guide for deduction of template arguments of 'nested_init_list<int>::concept_fail'}}
nested_init_list<int>::concept_fail nil_invalid{1, ""};
-// expected-note@#INIT_LIST_INNER_INVALID {{candidate template ignored: substitution failure [with F = const char *]: constraints not satisfied for class template 'concept_fail' [with F = const char *]}}
+// expected-note@#INIT_LIST_INNER_INVALID {{candidate template ignored: constraints not satisfied [with F = const char *]}}
+// expected-note@#INIT_LIST_INNER_INVALID_HEADER {{because 'const char *' does not satisfy 'False'}}
+// expected-note@#False {{because 'false' evaluated to false}}
// expected-note@#INIT_LIST_INNER_INVALID {{implicit deduction guide declared as 'template <False F> concept_fail(int, F) -> concept_fail<F>'}}
// expected-note@#INIT_LIST_INNER_INVALID {{candidate function template not viable: requires 1 argument, but 2 were provided}}
// expected-note@#INIT_LIST_INNER_INVALID {{implicit deduction guide declared as 'template <False F> concept_fail(concept_fail<F>) -> concept_fail<F>'}}
diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html
index c069e155fd547c..6f42d10e4c187c 100755
--- a/clang/www/cxx_dr_status.html
+++ b/clang/www/cxx_dr_status.html
@@ -14045,7 +14045,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
<td><a href="https://cplusplus.github.io/CWG/issues/2369.html">2369</a></td>
<td>CD6</td>
<td>Ordering between constraints and substitution</td>
- <td class="unknown" align="center">Unknown</td>
+ <td class="partial" align="center">Partial</td>
</tr>
<tr id="2370">
<td><a href="https://cplusplus.github.io/CWG/issues/2370.html">2370</a></td>
@@ -16464,7 +16464,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
<td><a href="https://cplusplus.github.io/CWG/issues/2770.html">2770</a></td>
<td>open</td>
<td>Trailing <I>requires-clause</I> can refer to function parameters before they are substituted into</td>
- <td align="center">Not resolved</td>
+ <td align="center">Clang 20</td>
</tr>
<tr id="2771">
<td><a href="https://cplusplus.github.io/CWG/issues/2771.html">2771</a></td>
More information about the cfe-commits
mailing list