Re: [gtk-osx-users] CoreAnimation: warning, deleted thread with uncommitted CATransaction.

[John Ralls <jralls ceridwen us>]

> On Dec 26, 2015, at 8:53 AM, Pascal <p p14 orange fr> wrote:
>
> Hello.
>
> I've got issues with the following warning:
>
> CoreAnimation: warning, deleted thread with uncommitted CATransaction; set CA_DEBUG_TRANSACTIONS=1 in 
> environment to log backtraces.
>
> And with export CA_DEBUG_TRANSACTIONS=1:
>
> CoreAnimation: warning, deleted thread with uncommitted CATransaction; created by:
> 0   QuartzCore                          0x00007fff89bcf8b6 _ZN2CA11Transaction4pushEv + 318
> 1   QuartzCore                          0x00007fff89bea372 _ZN2CA11Transaction15ensure_implicitEv + 276
> 2   QuartzCore                          0x00007fff89c4497a _ZN2CA11Transaction8set_seedEj + 30
> 3   QuartzCore                          0x00007fff89c4494f +[CATransaction(CATransactionPrivate) 
> generateSeed] + 56
> 4   AppKit                              0x00007fff908c0c0f +[NSDisplayCycle currentDisplayCycle] + 37
> 5   AppKit                              0x00007fff908c24e8 -[NSDisplayCycleObserver 
> setNeedsUpdateStructuralRegions:] + 34
> 6   AppKit                              0x00007fff904b87e6 -[NSThemeFrame _tileTitlebarAndRedisplay:] + 123
> 7   AppKit                              0x00007fff904b7e5f -[NSThemeFrame _updateButtons] + 3068
> 8   AppKit                              0x00007fff904a4636 -[NSThemeFrame 
> _floatTitlebarAndToolbarFromInit:] + 161
> 9   AppKit                              0x00007fff904a0fe9 -[NSThemeFrame initWithFrame:styleMask:owner:] + 
> 243
> 10  AppKit                              0x00007fff9049df74 -[NSWindow 
> _commonInitFrame:styleMask:backing:defer:] + 568
> 11  AppKit                              0x00007fff9049d657 -[NSWindow 
> _initContent:styleMask:backing:defer:contentView:] + 1475
> 12  AppKit                              0x00007fff9049d08d -[NSWindow 
> initWithContentRect:styleMask:backing:defer:] + 45
> 13  AppKit                              0x00007fff90692a4b -[NSWindow 
> initWithContentRect:styleMask:backing:defer:screen:] + 68
> 14  libgdk-3.0.dylib                    0x0000000101296fc9 -[GdkQuartzNSWindow 
> initWithContentRect:styleMask:backing:defer:screen:] + 153
> 15  libgdk-3.0.dylib                    0x00000001012a7766 _gdk_quartz_display_create_window_impl + 1318
>
> My program is multi-threaded with no problem since I upgraded to MacOS 10.11 and XCode 7.
>
> In fact it's more than a simple warning because the thread is deleted.
>
> There are some clues on:
> http://stackoverflow.com/questions/12507193/coreanimation-warning-deleted-thread-with-uncommitted-catransaction
>
> Is it a GTK-OSX concern? How to solve it?
>
> Season greetings, Pascal.
> http://blady.pagesperso-orange.fr

The SO article you cite indicates that this is a thread lifetime issue. One of the requirements of using Gtk 
or Quartz in a multi-threaded environment is that all GUI operations take place in the main thread and that 
other threads use idle events for synchronization. If you can create a simple demonstration program that 
raises the warning within that constraint then by all means file a bug against gtk+, quartz backend. 
Otherwise the problem is likely that your code violates the single-GUI-thread constraint.

Regards,
John Ralls