Compiling an extension with --compiler=mingw32 with official python 2.7.3 distribution on Windows (64bit) leads to unusable result - crash on module load ("invalid access to memory").

The reasons is that Lib/distutils/cygwincompiler.py#l62 links the resulting .pyd file against msvcr90.dll (version is determined by version of MSVC used to build python itself), while python27.dll is linked against msvcrt.dll (shows the Dependency Walker). 

Based on my own experience (above) and MSDN docs http://msdn.microsoft.com/en-us/library/abx4dbyh.aspx,  http://msdn.microsoft.com/en-us/library/ms235460.aspx), loading 2 different runtimes is asking for trouble.

I raised this topic on distutils-sig, hoping for an explanation. Judging by the reaction, it is quite possibly historical relict which is no longer needed. This is also hinted at by comments at the beginning of Lib/distutils/cygwincompiler.py

   "if you use a msvc compiled python version (1.5.2)"
   "mingw gcc 3.2/ld 2.13 works"

I am aware of distutils being frozen for new features (unless you want to call bugfix a new feature).