My Python / wxPython app crashing - suggestions?

[Ross]

I have a rather elaborate app on python 2.5.2 on mac osx 10.4.11. The
GUI elements are built on wxPython 2.8.10.1. Development has gone
pretty well, but I've got an intermittent rather silent crash that
happens without spewing any error messages to my console at all.

I'm developing in Eclipse with PyDev, and I build with py2app to make
an executable app.

Whether in Eclipse/PyDev or running standalone, the crash occurs
randomly without any messages almost every run, though it takes me 10
-15min of usage before I get the fateful crash. The only data I can
get is from the CrashReporter Log directory where a MyApp.crash.log
tells me that Thread 4 crashed with:

Thread: 4

Exception: EXC_BAD_ACCESS (0x0001)
Codes: KERN_PROTECTION_FAILURE (0x0002) at 0x00000004

and:

Thread 4 crashed with X86 Thread State (32-bit):
eax: 0x00000000 ebx: 0x9083d561 ecx: 0x00000074 edx: 0x92e341ac
edi: 0x14442b60 esi: 0x00000000 ebp: 0xb0370b58 esp: 0xb0370b58
ss: 0x0000001f efl: 0x00010286 eip: 0x92e30522 cs: 0x00000017
ds: 0x0000001f es: 0x0000001f fs: 0x00000000 gs: 0x00000037

Given the lack of other info, this doesn't tell me much. Any
suggestions?

One other (perhaps related issue?) very rarely, much less common than
the crash is a spurious malloc error from deep in python somewhere.
Not sure that my code is responsible. I don't recognize this format of
complaint.

Python(9544,0xa000d000) malloc: *** error for object 0x1a05c8f0:
double free
Python(9544,0xa000d000) malloc: *** set a breakpoint in szone_error
to debug

Can anyone suggest somewhere to start? If I start putting random
breakpoints and prints in trying to catch the crash, I could be here
for years as I can't yet nail down the conditions that precipitate it.

Regards,
Ross.