[PATCH] D30991: [Driver] Fix cross compiling with Visual Studio 2017

[Hamza Sood via Phabricator via cfe-commits]

hamzasood added a comment.

In https://reviews.llvm.org/D30991#702941, @thakis wrote:

> What env vars are needed here? Reading an env file seems a bit inelegant, could we pass the values of these env vars as flags instead?
>
> For example, MSVC2015 needs %INCLUDE%, but for cross-compiling (and for building on Windows without requiring env vars to be set we added the -imsvc flag instead of doing something like this.


The windows dynamic linker uses %PATH% to determine the location of dlls to load <https://msdn.microsoft.com/en-us/library/7d83bc18.aspx>. link.exe is linked against dlls in a directory that usually wouldn't be in %PATH%, so launching link.exe will fail if the environment isn't modified.


https://reviews.llvm.org/D30991