On 11/4/2013 10:21 AM, Mateusz Loskot wrote: > I don't care about MinGW/Cygwin myself, but AFAIR, there is no > detection mechanism > for those, only -m64 flag juggling. You could look at the compiler id and related variables: http://www.cmake.org/cmake/help/v2.8.12/cmake.html#variable:CMAKE_LANG_COMPILER_ID -Bill