Bug 22436 - SIGSEGV in sgen_par_object_get_size
Summary: SIGSEGV in sgen_par_object_get_size
Alias: None
Product: Runtime
Classification: Mono
Component: GC ()
Version: 3.6.0
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2014-08-27 21:29 UTC by Lance Hepler
Modified: 2017-07-12 22:55 UTC (History)
4 users (show)

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

Log of internal test job that crashes (110.39 KB, text/x-log)
2014-08-27 21:29 UTC, Lance Hepler

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.

Please create a new report on GitHub or Developer Community with your current version information, steps to reproduce, and relevant error messages or log files if you are hitting an issue that looks similar to this resolved bug and you do not yet see a matching new report.

Related Links:

Description Lance Hepler 2014-08-27 21:29:21 UTC
Created attachment 7846 [details]
Log of internal test job that crashes

Built from branch

Looks like the crash is in Thread 13 around sgen-gc.h:767 which is in sgen_par_object_get_size(...) and reads:

  mword descr = (mword)vtable->gc_descr;

Possibly a null pointer dereference?

I've tried to build a minimal testcase, but I can only trigger this crash very rarely. Trying again with reduced nursery size, but any additional pointers would be most appreciated.

It should also be noted that we're using the MathNET.Numerics MKL native provider, as you can see in the logs. It's possible that might have something to do with the problem... though based on the stacktrace I can't see how.
Comment 1 Mark Probst 2014-08-28 13:56:38 UTC
Could you test this with mono master?  We fixed a GC bug there recently.

If the bug still persists with master, please provide a test case.
Comment 2 Ludovic Henry 2017-07-12 22:55:03 UTC
Can you still reproduce with latest version of mono? If you can, please reopen and provide a repro case. Thank you