https://github.com/zyn0217 created https://github.com/llvm/llvm-project/pull/140680
For a dependent variable template specialization, we don't build a dependent Decl node or a DeclRefExpr to represent it. Instead, we preserve the UnresolvedLookupExpr until instantiation. However, this approach isn't ideal for constraint normalization. We consider the qualifier during profiling, but since that's based on the written code, it can introduce confusing differences, even when the expressions resolve to the same declaration. This change profiles the underlying VarTemplateDecl if UnresolvedLookupExpr is used to model a dependent use of it. Fixes https://github.com/llvm/llvm-project/issues/139476 >From c7b2fde04d708279fcd9a82fd59eb84290a8955a Mon Sep 17 00:00:00 2001 From: Younan Zhang <zyn7...@gmail.com> Date: Tue, 20 May 2025 13:48:28 +0800 Subject: [PATCH 1/2] Reapply "[Clang] Profile singly-resolved UnresolvedLookupExpr with the declaration" (#140655) This reverts commit 383e5f3e2da5c11ecbf1482eb0c39df38ac84e59. --- clang/docs/ReleaseNotes.rst | 1 + clang/lib/AST/StmtProfile.cpp | 5 ++++- .../SemaTemplate/concepts-out-of-line-def.cpp | 15 +++++++++++++++ 3 files changed, 20 insertions(+), 1 deletion(-) diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index f04cb7b91788c..4c839303f3621 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -741,6 +741,7 @@ Bug Fixes to C++ Support - Fixed the handling of pack indexing types in the constraints of a member function redeclaration. (#GH138255) - Clang now correctly parses arbitrary order of ``[[]]``, ``__attribute__`` and ``alignas`` attributes for declarations (#GH133107) - Fixed a crash when forming an invalid function type in a dependent context. (#GH138657) (#GH115725) (#GH68852) +- Fixed a function declaration mismatch that caused inconsistencies between concepts and variable template declarations. (#GH139476) - Clang no longer segfaults when there is a configuration mismatch between modules and their users (http://crbug.com/400353616). - Fix an incorrect deduction when calling an explicit object member function template through an overload set address. - Fixed bug in constant evaluation that would allow using the value of a diff --git a/clang/lib/AST/StmtProfile.cpp b/clang/lib/AST/StmtProfile.cpp index f7d1655f67ed1..19db338f760ba 100644 --- a/clang/lib/AST/StmtProfile.cpp +++ b/clang/lib/AST/StmtProfile.cpp @@ -2189,7 +2189,10 @@ StmtProfiler::VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *S) { void StmtProfiler::VisitOverloadExpr(const OverloadExpr *S) { VisitExpr(S); - VisitNestedNameSpecifier(S->getQualifier()); + if (S->getNumDecls() == 1) + VisitDecl(*S->decls_begin()); + else + VisitNestedNameSpecifier(S->getQualifier()); VisitName(S->getName(), /*TreatAsDecl*/ true); ID.AddBoolean(S->hasExplicitTemplateArgs()); if (S->hasExplicitTemplateArgs()) diff --git a/clang/test/SemaTemplate/concepts-out-of-line-def.cpp b/clang/test/SemaTemplate/concepts-out-of-line-def.cpp index e5d00491d3fb8..bf505dec0ca14 100644 --- a/clang/test/SemaTemplate/concepts-out-of-line-def.cpp +++ b/clang/test/SemaTemplate/concepts-out-of-line-def.cpp @@ -853,3 +853,18 @@ template <int... Ts> requires C<Ts...[0]> auto TplClass<int>::buggy() -> void {} } + +namespace GH139476 { + +namespace moo { + template <typename T> + constexpr bool baa = true; + + template <typename T> requires baa<T> + void caw(); +} + +template <typename T> requires moo::baa<T> +void moo::caw() {} + +} >From a450de85c4a70dbe1bc168d5b7f0c5f603104fa7 Mon Sep 17 00:00:00 2001 From: Younan Zhang <zyn7...@gmail.com> Date: Tue, 20 May 2025 13:48:50 +0800 Subject: [PATCH 2/2] Only profile Decls for dependent VarTemplates --- clang/lib/AST/StmtProfile.cpp | 9 ++++++--- clang/test/SemaCXX/exception-spec.cpp | 21 +++++++++++++++++++++ 2 files changed, 27 insertions(+), 3 deletions(-) diff --git a/clang/lib/AST/StmtProfile.cpp b/clang/lib/AST/StmtProfile.cpp index 19db338f760ba..2f1dec434c30b 100644 --- a/clang/lib/AST/StmtProfile.cpp +++ b/clang/lib/AST/StmtProfile.cpp @@ -2189,11 +2189,14 @@ StmtProfiler::VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *S) { void StmtProfiler::VisitOverloadExpr(const OverloadExpr *S) { VisitExpr(S); - if (S->getNumDecls() == 1) + bool DescribingDependentVarTemplate = + S->getNumDecls() == 1 && isa<VarTemplateDecl>(*S->decls_begin()); + if (DescribingDependentVarTemplate) { VisitDecl(*S->decls_begin()); - else + } else { VisitNestedNameSpecifier(S->getQualifier()); - VisitName(S->getName(), /*TreatAsDecl*/ true); + VisitName(S->getName(), /*TreatAsDecl*/ true); + } ID.AddBoolean(S->hasExplicitTemplateArgs()); if (S->hasExplicitTemplateArgs()) VisitTemplateArguments(S->getTemplateArgs(), S->getNumTemplateArgs()); diff --git a/clang/test/SemaCXX/exception-spec.cpp b/clang/test/SemaCXX/exception-spec.cpp index 6ad19aab397bd..31c691b28da4b 100644 --- a/clang/test/SemaCXX/exception-spec.cpp +++ b/clang/test/SemaCXX/exception-spec.cpp @@ -52,3 +52,24 @@ namespace AssignmentOp { D2 &operator=(const D2&); // expected-error {{more lax}} }; } + +namespace OverloadedFunctions { + +template <typename T> +void f(T&) noexcept; + +template <typename T, int N> +void f(T (&arr)[N]) noexcept(noexcept(f(*arr))); + +template <typename T> +inline void f(T&) noexcept {} + +template <typename T, int N> +inline void f(T (&arr)[N]) noexcept(noexcept(f(*arr))) {} + +void g() { + int x[1]; + f(x); +} + +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
