CMake : Compiling for different hardware architectures

• GCC (on Linux) or Sun Studio

Use compile option -m32 (force 32-bit build), -m64 (force 64-bit build)

• Windows, Visual Studio generator

Use cmake -G "Visual Studio 9 2008 Win64" path_to_source_dir to compile 64-bit (x64)

• Mac OS X

Use CMAKE_OSX_ARCHITECTURES CMake variable. You can set more than a single architecture to create universal binary, e.g

 cmake "-DCMAKE_OSX_ARCHITECTURES=i386;pcc" path_to_source 

will build universal binary with 32-bit intel / 32-bit powerpc.

cmake "-DCMAKE_OSX_ARCHITECTURES=x86_64" path_to_source 

will create x86_64 binary.

• NMake Makefiles
  for 64 bits use the right SetEnv ou vsvarsall.bat command line and then
  cmake path to source -G "NMake Makefiles"
  nmake

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