[CMake] OS/Compiler Versioning for External Libs

[Brad King]

Brian Hone wrote:
> I'm working on such a C program, based on the information at:
> 
> http://predef.sourceforge.net/prearch.html
> 
> Do you think it would make sense to integrate compiler version as a 
> command?  It doesn't look to hard to implement a new cmCommand. 

If it is provided by CMake at all it should be a 
CMAKE_C_COMPILER_VERSION variable that gets set automatically.  The 
problem is that determining the version requires specific per-compiler 
knowledge so it is not guaranteed that a version is available for a new 
compiler.  It should probably be provided anyway with documentation that 
says it may be available only on known compilers.  Please add this as a 
feature request here:

http://www.cmake.org/Bug

I don't know when we can get to this, though.

-Brad