GTK3: crash when deleting a stacked path effect in the path effect editor

[su_v]

Inkscape built and running with GTK3 crashes when removing one of two or more stacked path effects in the Path Effects editor.

Sample steps to reproduce:
1) launch inkscape (new default preferences)
2) switch to the pencil tool
3) change mode to 'Spiro splines'
4) change shape to e.g. 'Ellipse'
5) scribble a path
6) open 'Path > Path Effects…'
7) delete the 'Spiro spline' path effect

--> crash:
Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x00000000000000d0
0x000000010069cc6c in LivePathEffectObject::get_lpe (this=0x0) at lpeobject.h:44
44 Inkscape::LivePathEffect::Effect * get_lpe() { return lpe; };

Tested with Inkscape 0.48+devel r11497 on OS X 10.7.4
glib 2.32.2, gtk3/x11 3.4.2, gtkmm 3.4.0

Not reproduced with Inkscape 0.48+devel r11497 built and running with GTK2.

[Alex Valavanis (valavanisalex)]

We need to figure out where the Glib warnings are coming from:

GLib-GObject-WARNING **: value "-inf" of type `gdouble' is invalid or out of range for property `lower' of type `gdouble'

We can trap the cause of these by setting "br g_logv" in gdb before running the program. Unfortunately, it freezes my Xserver. I'll try attaching to the process using a terminal emulator at some point. If anyone gets there first, a backtrace would be very useful!

[su_v (suv-lp)]

> Unfortunately, it freezes my Xserver.

Maybe this tip helps:
<http://developer.gnome.org/gtk-faq/stable/x461.html>

[Alex Valavanis (valavanisalex)]

Great! Thanks for the advice :-)

[su_v (suv-lp)]

Another backtrace, this time with debug symbols for glib 2.32.3 available.

(still working on creating & keeping them for GTK3 as well - MacPorts doesn't offer them as packages ;-) )

[su_v (suv-lp)]

Attaching backtrace 2 (r11499) with debug symbols for GTK3 available …

>> Unfortunately, it freezes my Xserver.

If GTK3 was compiled with '--enable-debug=yes', possibly setting GDK_DEBUG=nograbs is another workaround to prevent freezing of the X server (or using the command line option '--gdk-debug nograbs'). According to Google this might cause some parts of the GUI to act strangely ;)

See also:
<http://developer.gnome.org/gtk3/3.4/gtk-running.html#GDK-Debug-Options>

[Alex Valavanis (valavanisalex)]

The bounds checking on SpinButtons appears to be stricter in GTK+ 3. I've changed the default bounds for scalar parameters from Geom::infinity to G_MAXDOUBLE (the limit for SpinButtons) in lp:inkscape r11794, which gets rid of the Glib warnings. However, it doesn't fix the crash.

[Beluga (buovjaga)]

Still crashing.

Arch Linux 64-bit, KDE Plasma 5
Inkscape 0.92pre1 15073 (GTK3)

[jazzynico (jazzynico)]

Also reproduced on Xubuntu 16.04, lp:inkscape rev. 15196.

[Jabiertxof (jabiertxof)]

This patch fix it.

[jazzynico (jazzynico)]

Patch tested successfully on Xubuntu 16.04.
Thanks!

[Jabiertxof (jabiertxof)]

commited on r.15200
Thanks jazzynico for test!