Bug 39679 - ReflectionTypeLoadException after some reflection stuff
Summary: ReflectionTypeLoadException after some reflection stuff
Alias: None
Product: Android
Classification: Xamarin
Component: Mono runtime / AOT Compiler ()
Version: 7.3 (15.2)
Hardware: PC Windows
: Normal normal
Target Milestone: ---
Assignee: Jonathan Pryor
Depends on:
Reported: 2016-03-16 10:17 UTC by Boris Spinner
Modified: 2017-06-28 08:19 UTC (History)
3 users (show)

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

small app that shows this issue (16.40 KB, application/x-zip-compressed)
2016-08-19 09:32 UTC, andrii.kozhyn

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Description Boris Spinner 2016-03-16 10:17:09 UTC
I'm having the same or similar problem as described by #17726 right now.

Crashes at this line: https://github.com/mono/mono/blob/b7a308f660de8174b64697a422abfc7315d07b8c/mcs/class/corlib/System.Reflection.Emit/AssemblyBuilder.cs#L752

The ReflectionTypeLoadException has one exception attached with this error message:

	Type '__callback_factory__class__' is not finished

It happens after calling 

	var types = from a in assemblies
		from ti in a.DefinedTypes
		where ti.IsDefined(typeof(TypeAliasAttribute), false)
		where baseType.IsAssignableFrom(ti)
		select ti.AsType();

And iterating over the enumerable (e.g. by using foreach or calling ToList()).
I observed this behavior on Android only. Tested on iOS and works.
Comment 1 Boris Spinner 2016-03-16 10:54:57 UTC
var types = from a in assemblies from ti in a.DefinedTypes select ti;

Is enough for me to get a crashing app.

Seems to be a specific assembly that leads to the crash. Just noticed the browsed assemblies can be reduced to one specific by now. Unfortunately I can't tell, which assembly lead to the error.
Comment 2 andrii.kozhyn 2016-08-19 09:32:40 UTC
Created attachment 17118 [details]
small app that shows this issue