[CMake] Testing for SSE and adding appropriate Compile options

[Michael Jackson]

I am testing for SSE2/SSE3 functionality and am having some issues  
getting things correct.

After I properly detect that SSE2/3 is available I need to set the  
COmpiler Flags. For GCC it seems I should use "-msse2" or -msse3  
flags. For MSVC it seems I should use /arch:SSE2. So I am trying to  
append to CMAKE_C_FLAGS and CMAKE_CXX_FLAGS
by doing the following:

set(CMAKE_C_FLAGS ${CMAKE_C_FLAGS} "-msse3")
set(CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS} "-msse3")

for NON MSVC compilers and

set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /arch:SSE2")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /arch:SSE2")

for MSVC compilers. The problem seems to be that, at least on windows  
that an extra ";" is also added, which makes sense as that is how  
CMake handles the concatenation of lists. So how best to append to the  
CMAKE_C_FLAGS?

Or should I be using the set_source_files_properties() for each file  
that needs to have SSE compile flags/options turned on?

Thanks
_________________________________________________________
Mike Jackson                  mike.jackson at bluequartz.net
BlueQuartz Software                    www.bluequartz.net
Principal Software Engineer                  Dayton, Ohio