CFRunLoop: do not wake a run loop the timer is not in - #141
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CFRunLoopTimerSetNextFireDate always called CFRunLoopWakeUp on the timer run loop, which is NULL until the timer is added to one, so setting the fire date of a free-standing timer dereferenced NULL. Only wake a run loop the timer has been added to.
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CFRunLoopTimerSetNextFireDate updated the fire date and then called CFRunLoopWakeUp on the timer's run loop. That run loop is NULL until the timer is added to one, so calling the function on a free-standing timer dereferenced NULL and crashed.
Only wake a run loop the timer has actually been added to.
Tests/CFRunLoop/timer_setfiredate.m sets the fire date of a timer that is not in a run loop and checks it took effect, verified against Apple CoreFoundation.