here is an update for libffi 3.0.11.  For now, only tested on x86-linux and arm-linux-gnueabi.  Proposing the check it in, and then test again, if the libffi_osx and libffi_msvc copies can be removed, if 3.0.11 works on these platforms (however I can't test on these myself).

New changeset 25421e1c48bb by doko in branch 'default':
- Issue #15194: Update libffi to the 3.0.11 release.
http://hg.python.org/cpython/rev/25421e1c48bb

Removing libffi_osx would be fairly hard due to the creation of fat binaries, the libffi_osx tree supports building all files using 'cc -arch i386 -arch ppc -arch x86_64', the regular libffi sources require a more complex dance (basically build all architectures separately then merge them together).

OTOH libffi_osx seems to have problems when using with recent versions of clang.

New changeset 989efaab9525 by doko in branch 'default':
- Issue #15194: check in the missing m4/ax_check_compile_flag.m4 file.
http://hg.python.org/cpython/rev/989efaab9525

New changeset 6fe974b8056c by doko in branch 'default':
- Issue #15194: check in the missing m4/ax_append_flag.m4 file.
http://hg.python.org/cpython/rev/6fe974b8056c

Few warnings when building trunk (on 10.6):

./Modules/_ctypes/libffi_osx/x86/x86-ffi64.c:49: warning: function declaration isn’t a prototype
./Modules/_ctypes/libffi_osx/x86/x86-ffi64.c:379: warning: function declaration isn’t a prototype

libffi_osx wasn't (yet) updated. so this seems to be unrelated to the 3.0.11 update.

3.0.13 is now in 2.7.4, 3.2.4, 3.3.1 and the trunk.