GC Crash

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#116,086 6 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
15/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
csharp, ios
Domain
mobile-dev

Research direction

Start by investigating the GC crash path named in the stack trace, especially simple_par_nursery_serial_scan_object in sgen-scan-object.h and the callers in sgen-marksweep.c, sgen-gc.c, and sgen-thread-pool.c. Establish a reproducible net8-iOS case using MONO_GC_PARAMS=mode=pause:20; done means identifying and fixing the crash while confirming the app no longer fails under the reported configuration.

Written by the indexing model from the issue text.

Description

area-GC-mono
Description

I see several crashes in Sentry (net8-iOS app) related to GC.
GC settings: MONO_GC_PARAMS=mode=pause:20

StackTrace:

OS Version: iOS 18.5 (22F76)
Report Version: 104

Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: SEGV_NOOP at 0x0000000000000028
Crashed Thread: 9

Application Specific Information:
Exception 1, Code 1, Subcode 40 >
KERN_INVALID_ADDRESS at 0x28.

Thread 9 Crashed:
0 Gambino.IOS 0x20323c97c simple_par_nursery_serial_scan_object (sgen-scan-object.h:98)
1 Gambino.IOS 0x2032338c8 scan_card_table_for_block (sgen-marksweep.c:2601)
2 Gambino.IOS 0x20321afe8 major_scan_card_table (sgen-marksweep.c:2683)
3 Gambino.IOS 0x2032130f8 job_scan_major_card_table (sgen-gc.c:1497)
4 Gambino.IOS 0x2032436a4 thread_func (sgen-thread-pool.c:204)
5 libsystem_pthread.dylib 0x43550b340 _pthread_start

Reproduction Steps

no steps

Expected behavior

no crash

Actual behavior

app crashes

Regression?

no crashes in xamarin

Known Workarounds

no Workarounds

Configuration

MONO_GC_PARAMS=mode=pause:20

Other information

No response

Dominant language
C#
Stars
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PR merge metrics
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