How to detect if 64 bit MSVC with cmake?

Question

I have a project which uses cmake, one target is set to only build with MSVC:

 if (MSVC)
     add_library(test SHARED source.cpp) 
 endif()

Answer 1

The optional solution is to build the condition base on used compiler name.

if(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")