[CMake] How to force use of Windows 64bit link.exe?

[Paul Smith]

Hi all.  I wonder if someone can help me get CMake to force Visual
Studio to run the 64bit linker instead of the 32bit linker.  By that I
mean, the link.exe binary built for 64bit, not a linker that produces a
64bit executable.

Sometimes (but not always) when I link my code I get an error from the
32bit link.exe and Visual Studio wants to automatically re-invoke the
64bit link.exe.  I would prefer that it just always starts with the
64bit version, rather than fail and retry.

I get errors like:

  LINK : the 32-bit linker
  (C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin\x86_amd64\link.exe)
  ran out of heap space; restarting link with the 64-bit linker

I run CMake with a generator like this:

  cmake.exe -G "Visual Studio 14 2015" -A x64 D:\builds\src

I want to convince cmake to tell Visual Studio to invoke the 64bit
link.exe at first, rather than waiting for a failure--the 64bit
link.exe is, I believe:

  C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin\amd64\link.exe

Does anyone know how to force that to happen?

BTW, I'm using CMake 3.5.2 at the moment.

Cheers!