[Distutils] Passing compiler options via the pydistutils.cfg file

[Phillip J. Eby]

At 10:02 AM 1/10/2008 -0800, kieran hervold wrote:
>I've run into a problem using mod_python under OS X Leopard: because
>the apache2 process runs in 64-bit mode, the python interpreter is
>forced into 64-bit mode, which breaks compatibility with any Python
>library with underlying C code.
>
>I suspect that adding a compiler flag specifying "-arch x86_64" to any
>gcc invocation would fix the problem, but I'd rather not do this
>package by package: I'd like to set one global parameter and be done
>with it.
>
>Apparently, I can add an entry to the global pydistutils.cfg file.
>However, I can't seem to find the appropriate parameter.  The
>pydistutils.cfg file follows the nomenclature of command-line setup.py
>invocation, but I haven't found a C compiler pass-through parameter
>for setup.py.
>
>Does such a parameter exist?

Apparently not:

$ python setup.py build_ext --help
...

Options for 'build_ext' command:
   --build-lib (-b)     directory for compiled extension modules
   --build-temp (-t)    directory for temporary files (build by-products)
   --inplace (-i)       ignore build-lib and put compiled extensions into the
                        source directory alongside your pure Python modules
   --include-dirs (-I)  list of directories to search for header files
                        (separated by ';')
   --define (-D)        C preprocessor macros to define
   --undef (-U)         C preprocessor macros to undefine
   --libraries (-l)     external C libraries to link with
   --library-dirs (-L)  directories to search for external C libraries
                        (separated by ';')
   --rpath (-R)         directories to search for shared C libraries at runtime
   --link-objects (-O)  extra explicit link objects to include in the link
   --debug (-g)         compile/link with debugging information
   --force (-f)         forcibly build everything (ignore file timestamps)
   --compiler (-c)      specify the compiler type
   --swig-cpp           make SWIG create C++ files (default is C)
   --swig-opts          list of SWIG command line options
   --swig               path to the SWIG executable
   --help-compiler      list available compilers


>   If I want to add a flag ("-arch x86_64",
>in this case) to the C compiler invocation, how do I pass that to
>setup.py?

There's probably an environment variable you can use, like CFLAGS or 
some such; check the distutils.sysconfig module to see if you can 
find something useful.

Otherwise, you may have to have apache run your setup.py files to do 
the building.