[pjmlp]

Their are done with C, there is no more love to give beyond what ANSI C++ requires.

ANSI C++14 requires C99 library, while ANSI C++17 upgraded it to C11.

Microsoft has contributed to improve clang on Windows for those that still want to keep on using C, but then good luck accessing COM and .NET APIs from C, it is possible but I wouldn't do it for fun.

Even the new C runtime library is actually written in C++.

[flohofwoe]

It would be fine with me if I could simply compile any valid C99 or even C11 code with Visual Studio C++ compiler, but C99 support is only half-assed, and C11 support probably will never happen.

D3D11's C API works fine (that's the only Windows API I care about apart from the usual Win32 windowing stuff), but already D3D12 let that rot and is only usable from C with workarounds (doesn't matter though since D3D12 is fairly niche).

All in all it's a shame though because the newer C features are much more sane and useful than anything in C++14 or C++17.

[pjmlp]

The name says it all, Visual Studio C++ compiler.

There is no written rule that C++ compilers are obliged to be C compilers as well.

Again, as C++ compiler, they are only required to be as compatible with C code as ANSI C++ requires.