[from python-dev]
I've found a recursion related crash in test_cpickle on 64bit builds. 
Specifically, the 'cPickleDeepRecursive' is causing a stack overflow,
and the debugger tells me the actual recursion depth was 629 at the crash.

The reason the 64bit build doesn't see more crashes is apparently due to
another regression in 2.6 - http://bugs.python.org/issue3373.  It
appears that in some cases, the recursion counter is actually
incremented *twice* for each entry, thereby causing the "maximum
recursion depth exceeded" exception to appear at a true recursion limit
of 500.  However, test_cpickle takes a different path and doesn't see
this doubling of the count - therefore dieing at the depth of 629 that I
can see.

My solution to this was to simply double the stack size for the
executables in 64bit builds, from 2MB to 4MB (2.1 and 4.2 for debug
builds.)  Is this an appropriate fix?