int main()
{
    GTK2.setup_gtk();
    object btn=GTK2.Button("Raise an exception");
    object win=GTK2.Window(0)->add(btn)->show_all();
    win->signal_connect("destroy",lambda() {exit(0);});
    btn->signal_connect("clicked",lambda() {error("Baboom!\n");});
    return -1;
}


Run this, click the button, then close the window. Pike will segfault.

Running a --with-debug Pike under gdb shows that the actual segfault
occurs in backend_callback (defined in GTK2/source/global.pre), where
it calls into the low end main loop for an iteration. Not immediately
helpful.

I suspect that something's getting corrupted - maybe in the Pike
stack, maybe something gets freed in GTK that should have another
reference - when the exception happens. How can I go about tracking
this down? Where would I put probes to watch for unexpected changes?

ChrisA