this seems to make a difference (at least for HP-UX 10.20)
even though config.h defines it.
+HP PA-RISC 2.0: A recent bug report (http://www.python.org/sf/546117)
+ suggests that the C compiler in this 64-bit system has bugs
+ in the optimizer that break Python. Compiling without
+ optimization solves the problems.
+
Minix: When using ack, use "CC=cc AR=aal RANLIB=: ./configure"!
SCO: The following apply to SCO 3 only; Python builds out of the box