Bug#757563: libgtk2.0-0: gdk_window_get_screen() should not be used for pixmaps

[Sebastian Gerhardt]

Package: libgtk2.0-0
Version: 2.24.24-1
Severity: normal

Dear Maintainers,

in the file gtk/gtkdnd.c in the function "gtk_drag_set_icon_pixmap"
there is a line
g_return_if_fail (!mask || gdk_window_get_screen (mask) == screen);

The parameter "mask" is a GdkBitmap*. 

I assume the second condition was changed from
gdk_drawable_get_screen(mask) because this call had been declared
deprecated in anticipation of later GTK/GDK versions.

But in the GDK version included in libgtk2.0-0(2.24.24-1) the
GDK_IS_WINDOW(window) assertion will fail if called with the above
parameter.


Therefore I suggest that, for libgtk versions < 3, this line be reverted
to:

g_return_if_fail (!mask || gdk_drawable_get_screen (mask) == screen);



This issue was found when dragging items on the desktop in the file
manager Caja for MATE. If
- it is built against GTK2 (which it is for Jessie) and
- composition is disabled,
only a fallback image will be displayed for the drag.

And the error messages are:
(caja:1541): Gdk-CRITICAL **: IA__gdk_window_get_screen: assertion
'GDK_IS_WINDOW (window)' failed

(caja:1541): Gtk-CRITICAL **: IA__gtk_drag_set_icon_pixmap: assertion '!
mask || gdk_window_get_screen (mask) == screen' failed


Best regards,
Sebastian


-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Versions of packages libgtk2.0-0 depends on:
ii  libatk1.0-0          2.12.0-1
ii  libc6                2.19-7
ii  libcairo2            1.12.16-2
ii  libcups2             1.7.4-4
ii  libfontconfig1       2.11.0-5
ii  libfreetype6         2.5.2-1
ii  libgdk-pixbuf2.0-0   2.30.7-1
ii  libglib2.0-0         2.40.0-3
ii  libgtk2.0-common     2.24.24-1
ii  libpango-1.0-0       1.36.3-1
ii  libpangocairo-1.0-0  1.36.3-1
ii  libpangoft2-1.0-0    1.36.3-1
ii  libx11-6             2:1.6.2-2
ii  libxcomposite1       1:0.4.4-1
ii  libxcursor1          1:1.1.14-1
ii  libxdamage1          1:1.1.4-2
ii  libxext6             2:1.3.2-1
ii  libxfixes3           1:5.0.1-2
ii  libxi6               2:1.7.4-1
ii  libxinerama1         2:1.1.3-1
ii  libxrandr2           2:1.4.2-1
ii  libxrender1          1:0.9.8-1
ii  multiarch-support    2.19-7
ii  shared-mime-info     1.3-1

Versions of packages libgtk2.0-0 recommends:
ii  hicolor-icon-theme  0.13-1
ii  libgtk2.0-bin       2.24.24-1

Versions of packages libgtk2.0-0 suggests:
ii  gvfs             1.20.2-1
ii  librsvg2-common  2.40.2-1

-- no debconf information