Ok, I think I have this worked out. GTK is throwing a critical warning,
and since notification-daemon calls
g_log_set_always_fatal (G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL) it
results in SIGTRAP where most GTK-using programs will just output a
message to stderr.
The problem seems to be that GtkStatusIcon defaults to a size of 4
somewhere, and then rounds this down to 0, and so tries to make a
zero-sized icon. If the critical warning doesn't terminate the program,
GtkStatusIcon will later on get a larger size and create an
appropriately-sized icon. As far as I can tell, older versions of GTK
didn't do this because they used a minimum size of GTK_ICON_SIZE_MENU
rather than 0 for GtkStatusIcons. I think this changed in
http://git.gnome.org/browse/gtk+/commit/gtk/gtkstatusicon.c?id=2e01dc1b7a134a6482f39ae7b3b6c840442c93db
in the block @@ -1364,9 +1327,9 @@.
This bug should probably be reassigned to gtk+3.0, since it has little
to do with notification-daemon. I've attached a small test program to
illustrate the problem. As a workaround, the g_log_set_always_fatal call
could be commented out in daemon.c.
/* Compile with:
gcc -g -Wall bug.c `pkg-config --cflags --libs gtk+-3.0` -o bug
*/
#include <gtk/gtk.h>
int main(int argc, char *argv[]) {
GtkStatusIcon *statusicon;
GIcon *icon;
// Remove this line to make it not crash on the critical error.
g_log_set_always_fatal (G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL);
gtk_init(&argc, &argv);
statusicon = gtk_status_icon_new();
gtk_status_icon_set_visible(statusicon, TRUE);
icon = g_themed_icon_new("help");
gtk_status_icon_set_from_gicon(statusicon, icon);
gtk_main();
return 0;
}
