nvcc fatal : Cannot find compiler 'cl.exe' in PATH although Visual Studio 12.0 is added to PATH

I had the same problem. I'm using 64 bit Windows 8.1 and I had to add the following to my path and now it works fine:

C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\bin\amd64

C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\bin\amd64\cl.exe

Hope this helps

The Visual Studio 2017 has it here

C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.14.26428\bin\Hostx64\x64