Python distutils, how to get a compiler that is going to be used?

Question

For example, I may use python setup.py build --compiler=msvc or python setup.py build --compiler=mingw32 or just python setup.py build, in which case the default compiler (say, bcpp) will be used. How can I get the compiler name inside my setup.py (e. g. msvc, mingw32 and bcpp, respectively)?

UPD.: I don't need the default compiler, I need the one that is actually going to be used, which is not necessarily the default one. So far I haven't found a better way than to parse sys.argv to see if there's a --compiler... string there.

Answer 1

This is an expanded version of Luper Rouch's answer that worked for me to get an openmp extension to compile using both mingw and msvc on windows. After subclassing build_ext you need to pass it to setup.py in the cmdclass arg. By subclassing build_extensions instead of finalize_options you'll have the actual compiler object to look into, so you can then get more detailed version information. You could eventually set compiler flags on a per-compiler, per-extension basis:

from distutils.core import setup, Extension
from distutils.command.build_ext import build_ext
copt =  {'msvc': ['/openmp', '/Ox', '/fp:fast','/favor:INTEL64','/Og']  ,
     'mingw32' : ['-fopenmp','-O3','-ffast-math','-march=native']       }
lopt =  {'mingw32' : ['-fopenmp'] }

class build_ext_subclass( build_ext ):
    def build_extensions(self):
        c = self.compiler.compiler_type
        if copt.has_key(c):
           for e in self.extensions:
               e.extra_compile_args = copt[ c ]
        if lopt.has_key(c):
            for e in self.extensions:
                e.extra_link_args = lopt[ c ]
        build_ext.build_extensions(self)

mod = Extension('_wripaca',
            sources=['../wripaca_wrap.c', 
                     '../../src/wripaca.c'],
            include_dirs=['../../include']
            )

setup (name = 'wripaca',
   ext_modules = [mod],
   py_modules = ["wripaca"],
   cmdclass = {'build_ext': build_ext_subclass } )