Hi all. I have implemented a patch for vala for safe manage situation like the one describe on this discution. The solution to call Idle.add(myfunc.callback) is not good for 2 reason: 1. performance. you go back to the mainloop 2. Idle.add has to have less priority that the function that you have to wakeup. my patch is attached. Can you test this patch with your code without modification for Idle.add(myfunc.callback) . If it is working I will try to put in on vala bugzilla, and, if we are lucky, it will be integrated officially. regards and thanks for any feedback 2016-03-20 14:02 GMT+01:00 marcin saepia net <marcin saepia net>:
Felipe, SIGSTOP is real signal issued by the OS that has stopped the execution. Michele, it seems you were right. I've changed all callback() calls to Idle.add(myfunc.callback) so I am 100% sure that they are async and crashes stopped to occur. I must admit that it was one of the weirdest bugs I've encountered ever. It caused for instance Soup.Session from libsoup to stop using custom TlsDatabase after some time and returing SSL error for all connections, or crashes in GLib's memory allocators. Awkward. I think such warning that code must be async in 100% cases should be explicitely added to the documentation. m. 2016-03-18 16:29 GMT+01:00 Felipe Lavratti <felipelav gmail com>:Hey, Why did you get a SIGSTOP on top of the stack trace? Is it emitted from the code you use to print the stacktrace or it is the real signal that stopped execution? On Fri, Mar 18, 2016 at 6:22 AM marcin saepia net <marcin saepia net> wrote:Felipe, it's non threaded. Michele, good hint! I will check that. m. 2016-03-18 6:47 GMT+01:00 <michele dionisio gmail com>:A crash can happes if you call the callback to wakeup before the yield. Are you completly sure that your code is completly asyncrounous in any condition. Il ven mar 18 01:05:05 2016 GMT+0100, Felipe Lavratti scrive:Hey Marcin, Just wondering, Is your program using threading or any threaded object that is handled in this part of code? On Thu, Mar 17, 2016 at 20:44 marcin saepia net <marcin saepia net> wrote:Hi all, I encounter random crashes in my app, which (it's my guess) is triggered when I call callback in async method. Such as public async void something() { SourceFunc callback_ref = something.callback; do_something_that_calls_another_callback(() => { callback_ref(); // here's crash happening. approximately 1/10000 calls }); yield; } The chain of async calls is nested. I get stack traces like this: https://gist.githubusercontent.com/mspanc/9ca4795f48e56149a9a2/raw/9be534c66409b26820a66d54f8610f2aa6306e1e/gistfile1.txt It's rather hard to believe that such basic thing as memory allocation is broken in GLib. Crash happens totally randomly, once per 1-3 days. You can imagine how hard is to collect test cases. I am trying to hunt more stack traces in order to find a pattern, but maybe in the meantime anyone here can share experience in debugging such issues? Or maybe there are some well-known bugs or antipatterns related to async functions that should be avoided? I use GLib 2.44 & Vala 0.30.0. I will try to upgrade to 2.46 but I see nothing related in the changelog. m. _______________________________________________ vala-list mailing list vala-list gnome org https://mail.gnome.org/mailman/listinfo/vala-list_______________________________________________ vala-list mailing list vala-list gnome org https://mail.gnome.org/mailman/listinfo/vala-list
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