Thematic Crash - hard to debug

[Riccardo Mottola]

Hello,

I am suffering a crash im Thematic as soon as I open the image inspector
of the theme. It happens on NetBSD/x86-32 with the gcc runtime.
- I am unable to get the libobjc2 runtime working on NetBSD yet, so no
comparison
- on Linux, both 32bit and 64bit, gcc or libobjc2 runtime I do not have
the issue nor does running valgrind show any useful result
- valgrind is not available on NetBSD

I get this if compiled with -O2

Program received signal SIGSEGV, Segmentation fault.
0xae562bde in objc_msg_lookup () from /usr/lib/libobjc.so.4
(gdb) bt
#0  0xae562bde in objc_msg_lookup () from /usr/lib/libobjc.so.4
#1  0x08055402 in -[ImagesView refreshCells] (self=<optimized out>,
    _cmd=0x8058f6f <-[ImageElement initWithView:owner:]+10162>) at
ImageElement.m:354
#2  0xab02c110 in ?? ()
Backtrace stopped: previous frame inner to this frame (corrupt stack?)

I compiled all GNUstep core in debug mode without -O2, but that doesn't
help getting a better stacktrace, but no help.
If I compile Thematic without -O2, I get no crash!

Thus I suppose there is a memory error which gets hidden without
optimization (addign lots of data can hide off-by one errors or such)
and that it is in Thematic but not in gnustep base/gui.

I tried compiling then -O1 and I think I finally obtain a useful stacktrace:

Program received signal SIGSEGV, Segmentation fault.
0xacc13be4 in objc_msg_lookup () from /usr/lib/libobjc.so.4
(gdb) bt


#0  0xb6cbdbe4 in objc_msg_lookup () from /usr/lib/libobjc.so.4
#1  0x08055467 in -[ImagesView refreshCells] (self=0x8054ef9
<-[ImagesView addObject:]+158>,
    _cmd=0xb3787290) at ImageElement.m:348
#2  0x08073248 in _OBJC_SELECTOR_TABLE ()
#3  0x08054ef9 in -[ImagesView addObject:] (self=0xb3787290,
    _cmd=0x8073330 <_OBJC_SELECTOR_TABLE+1136>, anObject=0xb2686100) at
ImageElement.m:172
#4  0x08058fa1 in -[ImageElement initWithView:owner:] (self=<optimized
out>,
    _cmd=0x806fc98 <_OBJC_SELECTOR_TABLE+1368>, aView=0xb380e410,
aDocument=0xb28260f0)
    at ImageElement.m:544
#5  0x0804d5d3 in -[ThemeDocument elementForView:] (self=0xb28260f0,
    _cmd=0x806fbf0 <_OBJC_SELECTOR_TABLE+1200>, aView=0xb380e410) at
ThemeDocument.m:472
#6  0x0804b86b in -[ThemeDocument changeSelection:at:] (self=0xb28260f0,
    _cmd=0x806fb60 <_OBJC_SELECTOR_TABLE+1056>, aView=0xb380e410,
mousePoint=...)
    at ThemeDocument.m:316
#7  0x0804d113 in -[ThemeDocumentView mouseDown:] (self=0xb2731b70,
    _cmd=0xb7789150 <_OBJC_SELECTOR_TABLE+3568>, theEvent=0xb27e67d0) at
ThemeDocument.m:207
#8  0xb753bf2f in -[NSWindow sendEvent:] (self=0xb26fba10,
    _cmd=0xb76b3cd0 <_OBJC_SELECTOR_TABLE+2448>, theEvent=0xb27e67d0) at
NSWindow.m:4154
#9  0xb7334d22 in -[NSApplication sendEvent:] (self=0xb3710e10,
    _cmd=0xb76b3c08 <_OBJC_SELECTOR_TABLE+2248>, theEvent=0xb27e67d0) at
NSApplication.m:2148
#10 0xb733336c in -[NSApplication run] (self=0xb3710e10, _cmd=0xb76a67c8
<_OBJC_SELECTOR_TABLE+936>)
    at NSApplication.m:1585
#11 0xb730f48d in NSApplicationMain (argc=argc@entry=1,
argv=argv@entry=0xbfb336c8) at Functions.m:123
#12 0x0806592e in gnustep_base_user_main (argc=1, argv=0xbfb336c8) at
main.m:31
#13 0xb6ef431f in main (argc=1, argv=0xbfb336c8, env=0xbfb336d0) at
NSProcessInfo.m:1008
#14 0x0804a056 in ___start ()
#15 0x08049d87 in _start ()

I set NSZombieEnabled=YES but I get a crash anyway! usually that should
save from such situations?

Riccardo