P0943R6 Supporting C Atomics In C++

[StephanTLavavej]

P0943R6 Supporting C Atomics In C++

Feature-test macro:
#define __cpp_lib_stdatomic_h 202011L

[XeonKHJ]

I'm still getting this error when compiling Electron 15.3.3 using MSVC 14.3.
C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.31.31103\include\stdatomic.h(15,2): error: <stdatomic.h> is not yet supported when compiling as C, but this is planned for a future release.
Same issue here https://issueantenna.com/repo/gnustep/libobjc2/issues/225

[CaseyCarter]

This proposal defines a <stdatomic.h> header that actually uses std::atomic so C11 code compiled as C++ works. We don't yet support atomics when actually compiling C, so such failures are expected.