https://github.com/AaronBallman updated https://github.com/llvm/llvm-project/pull/154351
>From 2dabc7de6840fb092c411a3e494ced6e970f5c47 Mon Sep 17 00:00:00 2001 From: Aaron Ballman <aa...@aaronballman.com> Date: Tue, 19 Aug 2025 10:43:35 -0400 Subject: [PATCH 1/2] [C] Fix issue with -Wimplicit-void-ptr-cast The changes from https://github.com/llvm/llvm-project/pull/136855 missed a change with atomic assignment constraints. This fixes a bug where we'd accidentally drop a non-atomic-to-atomic conversion step. Fixes #154157 --- clang/lib/Sema/SemaExpr.cpp | 8 ++++---- clang/test/Sema/implicit-void-ptr-cast.c | 8 ++++++++ 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 237c068f59283..265cd799373a5 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -9317,14 +9317,14 @@ AssignConvertType Sema::CheckAssignmentConstraints(QualType LHSType, // If we have an atomic type, try a non-atomic assignment, then just add an // atomic qualification step. if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(LHSType)) { - AssignConvertType result = + AssignConvertType Result = CheckAssignmentConstraints(AtomicTy->getValueType(), RHS, Kind); - if (result != AssignConvertType::Compatible) - return result; + if (!IsAssignConvertCompatible(Result)) + return Result; if (Kind != CK_NoOp && ConvertRHS) RHS = ImpCastExprToType(RHS.get(), AtomicTy->getValueType(), Kind); Kind = CK_NonAtomicToAtomic; - return AssignConvertType::Compatible; + return Result; } // If the left-hand side is a reference type, then we are in a diff --git a/clang/test/Sema/implicit-void-ptr-cast.c b/clang/test/Sema/implicit-void-ptr-cast.c index 3c3e153d1dbda..1a8e1574907d4 100644 --- a/clang/test/Sema/implicit-void-ptr-cast.c +++ b/clang/test/Sema/implicit-void-ptr-cast.c @@ -82,3 +82,11 @@ void more(void) { ptr3 = SOMETHING_THAT_IS_NOT_NULL; // c-warning {{implicit conversion when assigning to 'char *' from type 'void *' is not permitted in C++}} \ cxx-error {{assigning to 'char *' from incompatible type 'void *'}} } + +void gh154157(void) { + #define ATOMIC_VAR_INIT(value) (value) + + typedef const struct T * T_Ref; + static T_Ref _Atomic x = ATOMIC_VAR_INIT((void*)NULL); // c-warning {{implicit conversion when initializing '_Atomic(T_Ref)' with an expression of type 'void *' is not permitted in C++}} \ + cxx-error {{cannot initialize a variable of type '_Atomic(T_Ref)' with an rvalue of type 'void *'}} +} >From 9c2250cb2806753aacd5958b6aae86ee5a329a60 Mon Sep 17 00:00:00 2001 From: Aaron Ballman <aa...@aaronballman.com> Date: Tue, 19 Aug 2025 11:32:37 -0400 Subject: [PATCH 2/2] Add more tests based on review feedback --- clang/test/Sema/implicit-void-ptr-cast.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/clang/test/Sema/implicit-void-ptr-cast.c b/clang/test/Sema/implicit-void-ptr-cast.c index 1a8e1574907d4..f083cfb77329f 100644 --- a/clang/test/Sema/implicit-void-ptr-cast.c +++ b/clang/test/Sema/implicit-void-ptr-cast.c @@ -89,4 +89,8 @@ void gh154157(void) { typedef const struct T * T_Ref; static T_Ref _Atomic x = ATOMIC_VAR_INIT((void*)NULL); // c-warning {{implicit conversion when initializing '_Atomic(T_Ref)' with an expression of type 'void *' is not permitted in C++}} \ cxx-error {{cannot initialize a variable of type '_Atomic(T_Ref)' with an rvalue of type 'void *'}} + static T_Ref const y = ATOMIC_VAR_INIT((void*)NULL); // c-warning {{implicit conversion when initializing 'const T_Ref' (aka 'const struct T *const') with an expression of type 'void *' is not permitted in C++}} \ + cxx-error {{cannot initialize a variable of type 'const T_Ref' (aka 'const struct T *const') with an rvalue of type 'void *'}} + static T_Ref z = ATOMIC_VAR_INIT((void*)NULL); // c-warning {{implicit conversion when initializing 'T_Ref' (aka 'const struct T *') with an expression of type 'void *' is not permitted in C++}} \ + cxx-error {{cannot initialize a variable of type 'T_Ref' (aka 'const struct T *') with an rvalue of type 'void *'}} } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
