Bug 11677 - SGen: Assertion should not be reached in sgen-scan-object.h:109
Summary: SGen: Assertion should not be reached in sgen-scan-object.h:109
Alias: None
Product: iOS
Classification: Xamarin
Component: XI runtime ()
Version: 6.2.x
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2013-04-09 09:11 UTC by René Ruppert
Modified: 2013-11-19 17:20 UTC (History)
3 users (show)

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

Stack Trace (107.72 KB, image/png)
2013-04-09 09:11 UTC, René Ruppert

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Description René Ruppert 2013-04-09 09:11:38 UTC
Created attachment 3780 [details]
Stack Trace

XS 4.0.3

I've just gotten the assertion:

Assertion should not be reached in sgen-scan-object.h:109 

I cannot paste the full trace here because I cannot use copy&paste in XS due to another bug. Sigh. I attached a screenshot of the stack trace.
Comment 1 Mark Probst 2013-04-09 14:47:26 UTC
Can you give us the solution to reproduce this bug?
Comment 2 René Ruppert 2013-04-10 03:21:26 UTC
Sorry, no. I was doing something stupid but I thought you might be interested in the assertion.
What I did was basically:

public class Bar()
public void ButtonClicked(object sender EventArgs args)
// Assign the method and as the action assign the same method again.
IntDelegateMethod = foo(1, foo);


// Have a delegate that wants an "int" as only parameter.
public Action<int> IntDelegateMethod;

// A method that can be assigned to IntDelegateMethod because the second parameter is optional.
public void foo(int anInt, Action actionCallback = null)
if(actionCallback != null) actionCallback();


This crashes also if you debug and break in foo() and hover the "actionCallback" parameter.

After all it was just a search&replace problem and is pretty stupid code, but anyway I don't understand why it would crash.
Comment 3 PJ 2013-11-19 17:04:13 UTC
This bug has been in the NEEDINFO state with no changes for the last 90 days. Can we put this back into the NEW or CONFIRMED state, or are we still awaiting response?

If there is no change in the status of this bug over the next two weeks, this bug will be marked as NORESPONSE.
Comment 4 Mark Probst 2013-11-19 17:20:16 UTC
Doesn't look like there's a test case coming.