[PATCH] Modifies Windows toolchain to prefer link.exe from the MSVC folder rather than PATH and extends capability to implicitly find MSVC 11.0 includes and tools.

[David Ziman]

>>! In D4061#4, @rnk wrote:
> IMO we have to trust PATH before we start looking in hardcoded places.  The expectation is that the user will be running clang from a vcvars.bat shell, which is one that has INCLUDE, LIB, and PATH all set to point to the version of VS they wanted, which could be one of the many CTPs that we don't have listed here.
> 
> This is a real use case, it's how I test Clang with different versions of VS.  :)

I agree with you. Something like vcvars.bat is also essential to running cl.exe correctly. Does Clang like to behave more like cl.exe when the host is Windows and using the Windows toolchain? Or would it prefer to emulate GCC or other similar compiler and make some assumptions regarding paths? Is there a need for consistency?

http://reviews.llvm.org/D4061