c++c-preprocessorcompiler-optimizationdevelopment-environment

Optimizing code for various C/C++ compilers

For those that develop software for multiple platforms, how do you handle the potential that compilers might do certain things better than other compilers.

Say you develop for OS X, Windows, Linux and you are using Clang/LLVM, VS and GCC.

So if someone compiles your app on OS X and they are using GCC and another person compiles on OS X using the Intel Compilers and you could optimized sections of the code for the Intel compilers if the person has them.

Would you just check a Preprocessor directive?

#ifdef __GCC_
    // do it this way
#endif

#ifdef __INTEL__
    // do it this way
#endif

#ifdef __GCC_WITH C++_V11_Support__
    // do it this way
#endif

#idfef __WINDOWS_VISUAL_STUDIO
    // do it this way
#endif

Or is there a better way?

How does one find a list of what directive a compiler offers for checking compiler version, etc

Solution

  • Don't choose the implementation based on predefined macros. Let the build system control it.

    This lets you build and compare multiple implementations against each other during unit testing.