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Bug 51545 - [Crash] mono_threads_platform_set_priority: unknown policy 3
Summary: [Crash] mono_threads_platform_set_priority: unknown policy 3
Alias: None
Product: Android
Classification: Xamarin
Component: Mono runtime / AOT Compiler (show other bugs)
Version: 7.1 (C9)
Hardware: PC Mac OS
: High major
Target Milestone: 7.1 (C9)
Assignee: Ludovic Henry
Depends on:
Reported: 2017-01-15 10:09 UTC by David Karlaš
Modified: 2017-02-16 17:08 UTC (History)
6 users (show)

See Also:
Is this bug a regression?: ---
Last known good build:


Description David Karlaš 2017-01-15 10:09:37 UTC
This happens for me on Android emulator(didn't try real device) if I'm switching in and out of app a lot. It crashes with abort("mono_threads_platform_set_priority: unknown policy 3").

I'm assigning this to Henry since I think caused this.

Since I think this is serious regression I'm setting target to C9 and High priority.
Comment 1 Ludovic Henry 2017-02-08 19:54:32 UTC
The PR for C9 is available at and the trello card at

What are the next step to get it merged into C9?
Comment 2 Rodrigo Kumpera 2017-02-13 22:36:48 UTC
It was merged into mono, now it's up to the XA team to bump mono.

Comment 4 David Karlaš 2017-02-16 17:08:39 UTC
I'm verifying this is fixed, since now it just prints message but not crash application, which is exactly what fix is supposted to do:

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