[llvm] Support: unlock Windows API support, switch to Windows 10 RS1+ APIs (PR #102240)

[Martin Storsjö via llvm-commits]

mstorsjo wrote:

> > But I would want to object to bumping the requirement that far - within the msys2 project, they still support older versions
> 
> As stated at https://www.msys2.org/docs/windows_support/ MSYS2 targets Windows 8.1 for mingw-w64 but packages are free to require any Windows version. Many packages already won't run on anything older than Windows 10 since various compilers and libraries depend on newer APIs (for example, anything that uses Rust).

Ok, I see!

Anyway, the amount of APIs of this kind that we use/need is pretty small, so I don’t see a huge benefit in bumping the requirement (and in this case, making it fallback is quite easy). (A far more tricky aspect in these codepaths, is making them work properly with various less common file system drivers, like third party ramdisks and network mounts and similar.)

https://github.com/llvm/llvm-project/pull/102240