debugging gtk-engines?

[Jan de Groot <jan jgc homeip net>]

Hi,

With the latest gtk-engines 2.11 clearlooks engine, I get an invalid
free on running any wxgtk application. This error is caught by glibc,
which stops the program with a SIGABORT. This error does not happen when
reverting to the 2.10 package, or when using a different theme engine
like Mist.
All I get in this trace is an internal function of wxGTK, which seems to
call g_free. There's no reference to any theme engine in the valgrind
output and/or glibc assertion backtrace.

Do we have any ways to debug these problems in gtk engines?

The error when using wxgtk applications (vlc in this case) with
clearlooks 2.11:

==7158== Invalid free() / delete / delete[]
==7158==    at 0x402137F: free
(in /usr/lib/valgrind/x86-linux/vgpreload_memcheck.so)
==7158==    by 0x77929F0: g_free (in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x6EE977D: gtk_button_style_set_callback(_GtkWidget*,
_GtkStyle*, wxButton*) (in /usr/lib/libwx_gtk2u_core-2.8.so.0.0.0)
==7158==    by 0x6EE9E45: wxButton::SetDefault()
(in /usr/lib/libwx_gtk2u_core-2.8.so.0.0.0)
==7158==    by 0x6A4E4E0: wxvlc::Messages::Messages(intf_thread_t*,
wxWindow*) (in /usr/lib/vlc/gui/libwxwidgets_plugin.so)
==7158==    by 0x6A06943:
DialogsProvider::DialogsProvider(intf_thread_t*, wxWindow*)
(in /usr/lib/vlc/gui/libwxwidgets_plugin.so)
==7158==    by 0x6A0702F: CreateDialogsProvider(intf_thread_t*,
wxWindow*) (in /usr/lib/vlc/gui/libwxwidgets_plugin.so)
==7158==    by 0x69D3D66: Instance::OnInit()
(in /usr/lib/vlc/gui/libwxwidgets_plugin.so)
==7158==    by 0x69D585E: wxAppConsole::CallOnInit()
(in /usr/lib/vlc/gui/libwxwidgets_plugin.so)
==7158==    by 0x7166855: wxEntry(int&, char**)
(in /usr/lib/libwx_baseu-2.8.so.0.0.0)
==7158==    by 0x69D531D: Init(intf_thread_t*)
(in /usr/lib/vlc/gui/libwxwidgets_plugin.so)
==7158==    by 0x805E057: (within /usr/bin/vlc)
==7158==  Address 0x955B1A0 is 160 bytes inside a block of size 248
alloc'd
==7158==    at 0x4020990: memalign
(in /usr/lib/valgrind/x86-linux/vgpreload_memcheck.so)
==7158==    by 0x40209EA: posix_memalign
(in /usr/lib/valgrind/x86-linux/vgpreload_memcheck.so)
==7158==    by 0x77A69F3: slab_allocator_alloc_chunk
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x77A7BAF: g_slice_alloc
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x7789215: g_list_prepend
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x7784C3E: g_key_file_add_key
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x7787823: g_key_file_flush_parse_buffer
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x7787AC3: g_key_file_parse_data
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x7787D8B: g_key_file_load_from_fd
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x7788386: g_key_file_load_from_file
(in /usr/lib/libglib-2.0.so.0.1400.0)
==7158==    by 0x7375D55: insert_theme (gtkicontheme.c:931)
==7158==    by 0x737703E: ensure_valid_themes (gtkicontheme.c:1043)