[libcxx-commits] [libcxx] [libc++] Add a test for the ABI of std::once_flag (PR #218924)

[Nikolas Klauser via libcxx-commits]

philnik777 wrote:

@mstorsjo it looks like MinGW is the only platform where `sizeof(std::once_flag) != sizeof(void*)`. Do you think this should be changed, like it has been for MSVC?

https://github.com/llvm/llvm-project/pull/218924