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Created attachment 2049 [details]
Stack trace with native_to_managed_trampoline_MuddyTummy_UI_iOS_TableView_GroupedListSource_1_SectionIndexTitles.
As an aside this issue is showing in a similar section of code to the last one I entered (https://bugzilla.novell.com/show_bug.cgi?id=684281 imported as http://bugzilla.xamarin.com/show_bug.cgi?id=54).
Description of Issue:
When executed on device (debug or release) _sigtramp is signalled in context of UITableViewSource::SectionIndexTitles() call. Attached files shows stack trace.
Disabling the new trampolines by adding --noregistrar to mtouch arguments does not reproduce the issue.
If you note in the stack trace GroupedListSource is the context. The base class of this is a generic,
public abstract class Source<T> : UITableViewSource /* UITableViewDataSource and UITableViewDelegate combined */ where T : class
... foo ...
And GroupedListSource is derived from this thus,
public abstract class GroupedListSource<T> : Source<T> where T : class
public override string SectionIndexTitles(UITableView tableview)
... foo ...
Mac OS X 10.7.4
I expect that I can provide reduced code that reproduces the issue if required.
I tried the sample project here: https://bugzilla.novell.com/show_bug.cgi?id=684281#c7, but it works correctly, so I'd appreciate it if you could upload a new test case.
It doesn't have to be a reduced test case, registrar bugs are usually quite easy to find even with big test cases.
Created attachment 2094 [details]
Reduced test case.
Oddly there are two variants, at bottom of tableview main file, such that one will reproduce the __sigtramp and the other will not. The difference is an enum value passed as an argument.
Fixed (monotouch master: 2072b1a518044a346f5d9cb0f7ae09cb0b9dda7a).
The fix will be included in 5.3.5.
The crash happens when SectionIndexTitles returns null, so for a workaround you can just return an zero-length array instead in SectionIndexTitles until the next version is released.
Verified the workaround fixed the issue with 5.3.4. I'll wait on 5.3.5 to revert the change and re-verify. Thanks Rolf.
Verified fix in 5.3.5 Beta with my local code sans workaround. Thanks.