[Regression] cmake 3.18.0 Visual Studio generator may cause .c files to be compiled as C++
This appears to be a change in behaviour in 3.18.0 vs 3.17.x versions which may cause existing projects to break because .c files are compiled as C++ in Visual Studio.
This happens in mixed-language projects (C and C++ sources) if specific compiler options are set directly.
A minimal reproduction test case with detailed information how to trigger the regression is in this github repository
https://github.com/floooh/cmake318_vstudio_c_cpp_repro
Thanks for looking into this!