https://github.com/Backl1ght created https://github.com/llvm/llvm-project/pull/143244
fix https://github.com/llvm/llvm-project/issues/141789 The direct cause of infinite recursion is that `T` is changing from `struct X` and `S<X>` infinitely, this pr add a check that if `T` visited before then return false directly. ```plaintext /home/backlight/llvm-project/clang/lib/Sema/SemaDeclCXX.cpp:7196] FD->getType().getAsString()=struct X, T.getAsString()=S<X>, FD->getType().getCanonicalType().getUnqualifiedType().getAsString()=struct X, CanUnqualT.getAsString()=struct S<struct X>, /home/backlight/llvm-project/clang/lib/Sema/SemaDeclCXX.cpp:7196] FD->getType().getAsString()=S<X>, T.getAsString()=struct X, FD->getType().getCanonicalType().getUnqualifiedType().getAsString()=struct S<struct X>, CanUnqualT.getAsString()=struct X, ``` https://github.com/llvm/llvm-project/pull/104829 fix similar infinite recursion, but I think it is no longer needed so I kind of revert it. >From a52a1254a9eea86f332ff2c31c3f33dd57b8a288 Mon Sep 17 00:00:00 2001 From: Backl1ght <backlight....@gmail.com> Date: Sat, 7 Jun 2025 16:15:04 +0800 Subject: [PATCH] add visit check --- clang/lib/Sema/SemaDeclCXX.cpp | 14 ++++++-------- clang/test/SemaCXX/gh102293.cpp | 17 +++++++++++++++++ 2 files changed, 23 insertions(+), 8 deletions(-) diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp index 5ef2ae3ee857f..9f66c194a45dd 100644 --- a/clang/lib/Sema/SemaDeclCXX.cpp +++ b/clang/lib/Sema/SemaDeclCXX.cpp @@ -7172,7 +7172,10 @@ void Sema::CheckCompletedCXXClass(Scope *S, CXXRecordDecl *Record) { // "effectively constexpr" for better compatibility. // See https://github.com/llvm/llvm-project/issues/102293 for more info. if (isa<CXXDestructorDecl>(M)) { - auto Check = [](QualType T, auto &&Check) -> bool { + llvm::DenseSet<QualType> Visited; + auto Check = [&Visited](QualType T, auto &&Check) -> bool { + if (!Visited.insert(T).second) + return false; const CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); if (!RD || !RD->isCompleteDefinition()) @@ -7181,16 +7184,11 @@ void Sema::CheckCompletedCXXClass(Scope *S, CXXRecordDecl *Record) { if (!RD->hasConstexprDestructor()) return false; - QualType CanUnqualT = T.getCanonicalType().getUnqualifiedType(); for (const CXXBaseSpecifier &B : RD->bases()) - if (B.getType().getCanonicalType().getUnqualifiedType() != - CanUnqualT && - !Check(B.getType(), Check)) + if (!Check(B.getType(), Check)) return false; for (const FieldDecl *FD : RD->fields()) - if (FD->getType().getCanonicalType().getUnqualifiedType() != - CanUnqualT && - !Check(FD->getType(), Check)) + if (!Check(FD->getType(), Check)) return false; return true; }; diff --git a/clang/test/SemaCXX/gh102293.cpp b/clang/test/SemaCXX/gh102293.cpp index d4218cc13dcec..fe417e697841b 100644 --- a/clang/test/SemaCXX/gh102293.cpp +++ b/clang/test/SemaCXX/gh102293.cpp @@ -45,3 +45,20 @@ class quux : quux { // expected-error {{base class has incomplete type}} \ virtual int c(); }; } + +// Ensure we don't get infinite recursion from the check, however. See GH141789 +namespace GH141789 { +template <typename Ty> +struct S { + Ty t; // expected-error {{field has incomplete type 'GH141789::X'}} +}; + +struct T { + ~T(); +}; + +struct X { // expected-note {{definition of 'GH141789::X' is not complete until the closing '}'}} + S<X> next; // expected-note {{in instantiation of template class 'GH141789::S<GH141789::X>' requested here}} + T m; +}; +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
