I develop python extension modules for Trilinos, a large scientific 
computing project:

    http://trilinos.sandia.gov

Unit testing my extension modules under Mac OS X, I came across the 
following error messages after upgrading from gcc 4.0 to basically any 
higher version:

  python(65587) malloc: *** error for object 0x1715674: Non-aligned 
pointer being freed

Debugging the problem (which occurs for me in several places in several 
test scripts), the error was always being raised in the built-in C++ 
method

  ostream::operator<<(int)

which indicated to me that the problem was really probably somewhere 
else, and just being triggered in the ostream operator.

Trying to isolate the problem in a smaller script, I was unable to 
reproduce the error until I added

  import optparse

By the same token, I was able to eliminate the problem in my test 
scripts by getting rid of "import optparse".  I have changed these 
scripts now to use getopt, and they are running without error, but I 
thought I would report this strange behavior.

I realize after all of this that the problem might not actually be with 
optparse, but it sure seems like a likely culprit.  I would be happy to 
work with someone to try to reproduce the error, and then hopefully 
such a python expert would be able to find the actual issue.