I'd highly recommend contributing back "build features" to projects like cmake if it doesn't already exist so that you can simply enable a feature rather than hard-coding gcc-specific flags. Even something like clang takes a little work to shoehorn into a project that is enabling many gcc specific features. Abstracting the feature out means compiler front-ends don't have to mimic gcc to have a chance of working, and even allows more easily adapting to other POSIX platforms where gcc/clang are not the default compilers. E.g. if cmake doesn't support a robust enough way to specify LTO the way you need to in a project, consider helping add it. (Just picked some random feature)

Good point, if needed I'm sure we will.

Please tell me that msbuild has a replacement in the wings? Something capable of hermetic reproducible builds. PLEASE???