system/serenity
system/serenity
1
0
Fork 0
mirror of https://github.com/SerenityOS/serenity synced 2024-07-23 19:15:55 +00:00
Code Issues Actions 4 Packages Projects Releases Wiki Activity

AK: Fix Clang 16 UBSan issue with zero-length Array

Browse source 
The current implementation of `Array<T, 0>` has a zero-length C array as
its storage type. While this is accepted as a GNU extension, when
compiling with Clang 16, an UBSan error is raised every time an object
is accessed whose only field is a zero-length array.

This is likely a bug in Clang 16's implementation of UBSan, which has
been reported here: https://github.com/llvm/llvm-project/issues/61775
This commit is contained in:
Daniel Bertalan 2023-03-28 14:07:25 +02:00 committed by Tim Flynn
parent e77552519e
commit 0016f63547
1 changed files with 11 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
AK/Array.h
View file

@ -13,6 +13,16 @@
namespace AK {
namespace Detail {
// This type serves as the storage of 0-sized `AK::Array`s. While zero-length `T[0]`
// is accepted as a GNU extension, it causes problems with UBSan in Clang 16.
template<typename T>
struct EmptyArrayStorage {
T& operator[](size_t) const { VERIFY_NOT_REACHED(); }
constexpr operator T*() const { return nullptr; }
};
}
template<typename T, size_t Size>
struct Array {
using ValueType = T;
@ -109,7 +119,7 @@ struct Array {
return value;
}
T __data[Size];
Conditional<Size == 0, Detail::EmptyArrayStorage<T>, T[Size]> __data;
};
template<typename T, typename... Types>