https://github.com/bonktree created
https://github.com/llvm/llvm-project/pull/68435
When this file is included in a project compiled with GCC 13 `-Werror`,
compilation fails with the following diagnostic:
<pre>
/usr/lib/llvm-17.0/include/clang/AST/TypeLoc.h: In constructor
'clang::TypeSourceInfo::TypeSourceInfo(clang::QualType, size_t)':
/usr/lib/llvm-17.0/include/clang/AST/TypeLoc.h:245:9: error: 'void*
memset(void*, int, size_t)' clearing an object of non-trivial type 'class
clang::TypeSourceInfo'; use assignment instead [-Werror=class-memaccess]
245 | memset(this + 1, 0, DataSize);
| ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
</pre>
To avoid this, we add an explicit type cast. The cast to void makes sense,
since other member functions of `TypeSourceInfo` also treat the buffer `(this +
1)` of length `DataSize` as opaque memory, and was likely left out by mistake.
Fixes: 4498663f3de0 ("[AST] Initialized data after TypeSourceInfo")
I also suggest to apply this to release/17.x if possible.
>From 753c2e0ad0c15d0af14368c574b3fa53d70416f9 Mon Sep 17 00:00:00 2001
From: Arseny Maslennikov <ars...@altlinux.org>
Date: Thu, 5 Oct 2023 10:05:14 +0300
Subject: [PATCH] [AST] Use explicit type erasure in TypeSourceInfo constructor
When this file is included in a project compiled with GCC 13 -Werror,
compilation fails with the following diagnostic:
/usr/lib/llvm-17.0/include/clang/AST/TypeLoc.h: In constructor
'clang::TypeSourceInfo::TypeSourceInfo(clang::QualType, size_t)':
/usr/lib/llvm-17.0/include/clang/AST/TypeLoc.h:245:9: error: 'void*
memset(void*, int, size_t)' clearing an object of non-trivial type 'class
clang::TypeSourceInfo'; use assignment instead
+[-Werror=class-memaccess]
245 | memset(this + 1, 0, DataSize);
| ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
To avoid this, we add an explicit type cast. The cast to void makes
sense, since other member functions of TypeSourceInfo also treat the
buffer `(this + 1)` of length `DataSize` as opaque memory, and was
likely left out by mistake.
Fixes: 4498663f3de0 ("[AST] Initialized data after TypeSourceInfo")
---
clang/include/clang/AST/TypeLoc.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/clang/include/clang/AST/TypeLoc.h
b/clang/include/clang/AST/TypeLoc.h
index 98427a8dcbfe660..e38895099c9e30c 100644
--- a/clang/include/clang/AST/TypeLoc.h
+++ b/clang/include/clang/AST/TypeLoc.h
@@ -243,7 +243,7 @@ class TypeLoc {
inline TypeSourceInfo::TypeSourceInfo(QualType ty, size_t DataSize) : Ty(ty) {
// Init data attached to the object. See getTypeLoc.
- memset(this + 1, 0, DataSize);
+ memset(const_cast<void*>(static_cast<const void*>(this + 1)), 0, DataSize);
}
/// Return the TypeLoc for a type source info.
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
