GtkGesture is a GtkEventController. gtk_event_controller_dispose() calls
_gtk_widget_remove_controller(). That NULLs the pointer-to-Controller in
our EventControllerData but does not delete said ECData from our GList.
Subsequently, if that same Widget gets unparent()ed, that method calls
unset_state_flags(), which leads to doing reset_controllers() if we are
insensitive. Now, unlike most most other loops over the GList of ECData,
reset_controllers() does not skip nodes whose pointer-to-Controller is
NULL. So, we call gtk_event_controller_reset(NULL) and get a CRITICAL.
This surfaced in a gtkmm program. The Gesture is destroyed before the
Widget. The Widget then gets dispose()d, which calls unparent()… boom.
I didn’t find an MCVE yet but would hope this logic is correct anyway:
The simplest fix is to make the loop in gtk_widget_reset_controllers()
skip GList nodes with a NULL Controller pointer, like most other such
loops, so we avoid passing the NULL to gtk_event_controller_reset().
In other, live cases, _gtk_widget_run_controllers() loops over the GList
and removes/frees nodes having NULL Controllers, so that should suffice.
But this clearly was not getting a chance to happen in the failing case.
https://bugzilla.gnome.org/show_bug.cgi?id=792624
Filter models rely on views taking a ref on every node
they care about. GtkIconView was not doing that. Amazingly,
this has never shown up in a bug so far, until I spotted
the fallout in gnome-font-viewer.
Test that filter models propagate ::row-changed if there is
an external reference on the node, and not otherwise. This
is showing up in buggy icon view behaviour, where the icon
view is not redrawing if the content changes in a model that
is below a filter model.
We must notify the font and font-desc properties when the
list selection changes, and return NULL values for them
when there is no selection in the list.
We were failing to change the sort order for the
default sort column in some cases. Fix that, and
add a testcase for this issue.
https://bugzilla.gnome.org/show_bug.cgi?id=792459
Add a testcase for the previous fix
Some emoji fonts (such as Emoji One), render Emoji sequences
such as some of the family variations using multiple individual
glyphs. This rendering is too wide and breaks our grid layout.
Therefore, we will just skip any sequence whose rendering is
more than twice as wide as a simple smiley.
Both AC_TRY_COMPILE and AC_LANG_PROGRAM put code passed to their second
arguments to the body of the main function. This means that we cannot
and should not declare functions there, or we end up checking whether
the compiler support nested functions instead of whether a compiler or
linker flag is supported.
GCC supports nested functions and tests succeed. Clang doesn't support
nested functions, so tests fail and -fvisibility=hidden won't be used.
This means that functions which are not intended to be used by other
programs, such as gtk_menu_tracker*, gtk_action_observ*,
gtk_menu_muxer_*, become global symbols with default visibility.
GNOME Shell has a private library libgnome-shell-menu.so, which also has
symbols gtk_menu_tracker*, gtk_action_observ*, gtk_menu_muxer_* that are
intended to be used by GNOME Shell itself. When GNOME Shell still used
Autotools build system, the executable gnome-shell explicitly linked to
libgnome-shell-menu.so, so the linker loaded libgnome-shell-menu.so
before libgtk-3.so.0 and GNOME Shell used correct symbols from its
private library.
However, after GNOME Shell switched to Meson build system, gnome-shell
executable no longer lists libgnome-shell-menu.so as its dependency.
Even if we adds it to the build file, it won't be listed in DT_NEEDED of
gnome-shell because Meson uses -Wl,--as-needed by default. This causes
the runtime linker to load libgtk-3.so.0 before libgnome-shell-menu.so
and symbols gtk_menu_tracker*, gtk_action_observ*, gtk_menu_muxer_* are
bound to libgtk-3.so.0 instead of libgnome-shell-menu.so. GNOME Shell
hangs when opening more than one window because it uses functions from
the wrong library.
This problem is already fixed in OpenBSD ports. The article describing
it can be found on OpenBSD Journal with this link:
https://undeadly.org/cgi?action=article;sid=20170930133438https://bugzilla.gnome.org/show_bug.cgi?id=791943
