[pygtk] Apparent PyGTK Segmentation Fault

Thu Aug 21 22:46:43 WST 2008

We've seen similar problems.  My guess is that you have a stray  
pointer in a C or C++ extension module which is trashing some part of  
python's memory.  The first time you run the program after modifying  
it, python is creating .pyc files and so its memory usage is  
different from the second time, when it's not creating the files.   
Try removing the .pyc files and running again, without modifying the  
code.  It probably won't crash.

  -- Steve

On Aug 21, 2008, at 5:13 AM, Casey McGinty wrote:

> I've come across a strange segmentation fault in PyGTK. Some other  
> interesting debug notes:
>
> 1) The failure occurs when I click on a button widget that calls a  
> gtk.Menu.popup() function.
> 2) I notice the failure only when I connect to the gtk.Menu  
> 'deactivate' signal.
> 3) The failure only occurs on a 2nd or later run of the program  
> after a PyGTK code change. The 1st time the program runs, all is  
> fine. So, "code change", "run", "click button", all works fine.  
> Then "exit", "run", "click button" .... failure.
> 4) When I run only the PyGTK portion of my program, the bug can not  
> be reproduced. Even when connected to the 'deactivate' signal.
> 5) I have verified this behavior on two different systems.
>
> I am open to any debug suggestions or possible solutions. I am  
> working on building SVN versions of PyGTK and PyGObject. Is there  
> any document on how to quickly setup an environment to debug PyGTK?
>
> Here is a back trace of the failure.
>
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread 0xb7e1f8c0 (LWP 14598)]
> 0xb7a23b80 in ?? () from /var/lib/python-support/python2.5/gtk-2.0/ 
> gtk/_gtk.so
> (gdb) bt
> #0  0xb7a23b80 in ?? ()
>    from /var/lib/python-support/python2.5/gtk-2.0/gtk/_gtk.so
> #1  0x080c9ab3 in PyEval_EvalFrameEx (f=0x859b9dc, throwflag=0)
>     at ../Python/ceval.c:3573
> #2  0x080cb1f7 in PyEval_EvalCodeEx (co=0xb6e37770,  
> globals=0xb6d4035c,
>     locals=0x0, args=0xb7da4a38, argcount=4, kws=0x0, kwcount=0,  
> defs=0x0,
>     defcount=0, closure=0x0) at ../Python/ceval.c:2836
> #3  0x0811372e in function_call (func=0xb6d3fb1c, arg=0xb7da4a2c,  
> kw=0x0)
>     at ../Objects/funcobject.c:517
> #4  0x0805cb97 in PyObject_Call (func=0x8145720, arg=0xb7da4a2c,  
> kw=0x0)
>     at ../Objects/abstract.c:1861
> #5  0x08062bfb in instancemethod_call (func=0xb6d3fb1c,  
> arg=0xb7da4a2c, kw=0x0)
>     at ../Objects/classobject.c:2519
> #6  0x0805cb97 in PyObject_Call (func=0x8145720, arg=0xb6d477ac,  
> kw=0x0)
>     at ../Objects/abstract.c:1861
> #7  0x080c2e9c in PyEval_CallObjectWithKeywords (func=0xb7dd3374,
>     arg=0xb6d477ac, kw=0x0) at ../Python/ceval.c:3442
> #8  0x0805d040 in PyObject_CallObject (o=0xb7dd3374, a=0xb6d477ac)
>     at ../Objects/abstract.c:1852
> #9  0xb7b28afb in ?? ()
>    from /var/lib/python-support/python2.5/gtk-2.0/gobject/_gobject.so
> #10 0xb7b7c759 in g_closure_invoke () from /usr/lib/ 
> libgobject-2.0.so.0
> #11 0xb7b90f8b in ?? () from /usr/lib/libgobject-2.0.so.0
> #12 0xb7b92947 in g_signal_emit_valist () from /usr/lib/ 
> libgobject-2.0.so.0
> #13 0xb7b92f69 in g_signal_emit () from /usr/lib/libgobject-2.0.so.0
> #14 0xb781a667 in ?? () from /usr/lib/libgtk-x11-2.0.so.0
> #15 0xb76f4b21 in gtk_propagate_event () from /usr/lib/libgtk- 
> x11-2.0.so.0
> #16 0xb76f5e92 in gtk_main_do_event () from /usr/lib/libgtk- 
> x11-2.0.so.0
> #17 0xb756ea9a in ?? () from /usr/lib/libgdk-x11-2.0.so.0
> #18 0xb7c45dd6 in g_main_context_dispatch () from /usr/lib/ 
> libglib-2.0.so.0
> #19 0xb7c49193 in ?? () from /usr/lib/libglib-2.0.so.0
> #20 0xb7c49577 in g_main_loop_run () from /usr/lib/libglib-2.0.so.0
> #21 0xb76f6264 in gtk_main () from /usr/lib/libgtk-x11-2.0.so.0
> #22 0xb7a75ee0 in ?? ()
>    from /var/lib/python-support/python2.5/gtk-2.0/gtk/_gtk.so
> #23 0x080ca5c6 in PyEval_EvalFrameEx (f=0x82f2854, throwflag=0)
>     at ../Python/ceval.c:3557
> #24 0x080c96e5 in PyEval_EvalFrameEx (f=0x81c2964, throwflag=0)
>     at ../Python/ceval.c:3659
> #25 0x080cb1f7 in PyEval_EvalCodeEx (co=0xb7da7410,  
> globals=0xb7df8acc,
>     locals=0xb7df8acc, args=0x0, argcount=0, kws=0x0, kwcount=0,  
> defs=0x0,
>     defcount=0, closure=0x0) at ../Python/ceval.c:2836
> #26 0x080cb347 in PyEval_EvalCode (co=0xb7da7410, globals=0xb7df8acc,
>     locals=0xb7df8acc) at ../Python/ceval.c:494
> #27 0x080ea818 in PyRun_FileExFlags (fp=0x816b008,
>     filename=0xbf83b741 "scripts/riproar", start=257,  
> globals=0xb7df8acc,
>     locals=0xb7df8acc, closeit=1, flags=0xbf839548)
>     at ../Python/pythonrun.c:1273
> #28 0x080eaab9 in PyRun_SimpleFileExFlags (fp=0x816b008,
>     filename=0xbf83b741 "scripts/riproar", closeit=1,  
> flags=0xbf839548)
>     at ../Python/pythonrun.c:879
>
>
> _______________________________________________
> pygtk mailing list   pygtk at daa.com.au
> http://www.daa.com.au/mailman/listinfo/pygtk
> Read the PyGTK FAQ: http://www.async.com.br/faq/pygtk/

--
-- EMail: stephen.langer at nist.gov                    Phone: (301)  
975-5423 --
-- WWW:  http://math.nist.gov/mcsd/Staff/SLanger/    Fax:   (301)  
975-3553 --
-- Mail: NIST; 100 Bureau Drive -- Stop 8910; Gaithersburg, Md   
20899-8910 --

-- "I don't think this will work.  That's why it's  
science."               --
--                              Naomi Langer (age 6),  17 Feb  
2003         --