[PyQt] crash: *** glibc detected *** python: double free or corruption (fasttop): 0x0a802370 ***

[Tom Kuiper]

Greetings!

A pyQt4 application using QThread (I suspect this is relevant) crashed 
unpredictably with the above error message.  Searching the web I found 
this type of error in many diverse applications, not just Python or 
pyqt4.  I could not find a clue to resolving this problem.  I'm somewhat 
reluctant to post here the 120 lines of diagnostics so here are some 
parts that I suspect are relevant:

*** glibc detected *** python: double free or corruption (fasttop): 
0x0a802370 ***
======= Backtrace: =========
/lib/i686/cmov/libc.so.6[0xb7dd9624]
/lib/i686/cmov/libc.so.6(cfree+0x96)[0xb7ddb826]
/usr/lib/libstdc++.so.6(_ZdlPv+0x21)[0xb77142e1]
/usr/lib/libQtGui.so.4(_ZN7QRegion7cleanUpEPNS_11QRegionDataE+0x48)[0xb68e9558]
/usr/lib/libQtGui.so.4(_ZN7QRegionaSERKS_+0x3e)[0xb68e95ce]
...
python(PyRun_SimpleFileExFlags+0x19a)[0x80ee00a]
python(Py_Main+0xc07)[0x8059327]
python(main+0x22)[0x80586f2]
/lib/i686/cmov/libc.so.6(__libc_start_main+0xe5)[0xb7d81455]
python[0x8058631]
======= Memory map: ========
08048000-08143000 r-xp 00000000 08:01 1213624    /usr/bin/python2.5
08143000-08168000 rw-p 000fa000 08:01 1213624    /usr/bin/python2.5
08168000-0816e000 rw-p 08168000 00:00 0
094ce000-0ad3f000 rw-p 094ce000 00:00 0          [heap]
...
b2c33000-b2c35000 r--s 00000000 08:01 8522271    
/var/cache/fontconfig/646addb8444faa74ee138aa00ab0b6a0-x86.cache-2
b2c35000-b2c38000 r--s 00000000 08:01 8522270    
/var/cache/fontconfig/dfe01fa16583a85Aborted

I'm running an up-to-date Debian lenny with a 2.6.26-1-686 i686 
GNU/Linux kernel.

For any insights, many thanks.

Tom