Merge pull request #429 from JoesCat/master

sequence of checks done, different order, fixed error.
Fix for Irix 'struct timeval' complaint

See Re: [Fontforge-devel] problem in contextchain.c, 2013mar12
Irix complains about struct timeval.
Gnu keeps it in <time.h> but the BSDs keep it in <sys/time.h>
Make void * and function pointer arithmetic an error.

See Re: [Fontforge-devel] problem in contextchain.c, 2013mar12
Irix complains about void* pointer. Brackets required.

Patch fixed by jon banquer <banquersgear@gmail.com>  2013-03-12 22:49:45
Turn on -Wcast-align if it was not already enabled.

This ought to give no warnings on x86 or amd64, which support all the weird
alignments, but could help trap problems on other CPU architectures.
Turn on strict aliasing violation detection.
Let's avoid longjmp. strict-aliasing needs more attention.

Some discussion about Py_True/False
http://mail.python.org/pipermail/python-dev/2003-July/036898.html