Bug 11002 - [CorDebugger] Debugger can't step into and crashes in a generic method extension
Summary: [CorDebugger] Debugger can't step into and crashes in a generic method extension
Alias: None
Product: Xamarin Studio
Classification: Desktop
Component: Debugger ()
Version: 4.0.1
Hardware: PC Windows
: --- normal
Target Milestone: 4.2.3 (from master)
Assignee: Bugzilla
Depends on:
Reported: 2013-03-08 13:00 UTC by benoit.jacquier
Modified: 2014-01-06 04:09 UTC (History)
3 users (show)

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

solution and screenshot (73.02 KB, application/octet-stream)
2013-03-08 13:00 UTC, benoit.jacquier

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Description benoit.jacquier 2013-03-08 13:00:41 UTC
Created attachment 3561 [details]
solution and screenshot

Version: 4.0.1 ( build 9 )

When running the following program, i can't step-into the Compose method ( from line 31 )
After a few step into tries, a System.Reflection.TargetInvocationException is thrown
Please find attached the solution and a screenshot of the exception


using System;

namespace Monad
	public static class MyExtensions
		public static Func<T, V> Compose<T, U, V>(this Func<U, V> f, Func<T, U> g)
			return x => f(g(x));

	class MainClass
		static float AddOne( float input )
			return input + 1;

		static float MulByTwo( float input )
			return input * 2;

		public static void Main (string[] args)
			Func<float,float> addOne = AddOne;
			Func<float,float> mulByTwo = MulByTwo;

                        //Cannot stepinto here
			var r2 = addOne.Compose (mulByTwo) (3);
Comment 1 Jeffrey Stedfast 2013-03-08 17:41:18 UTC
Is this using the Microsoft .NET runtime? or the Mono runtime? (the default is Microsoft's)
Comment 2 benoit.jacquier 2013-03-09 08:00:36 UTC

now i am using Microsoft .NET runtime.
Comment 3 Jeffrey Stedfast 2013-03-09 08:25:40 UTC
Comment 4 Marius Ungureanu 2013-09-10 05:35:21 UTC
This has been fixed and will be shipped in future releases.
Comment 5 narayanp 2014-01-06 04:09:40 UTC
I have checked this issue with following builds:

All mac and Windows
X.S 4.2.3(build 24) for mac
X.S 4.2.3(build 23) for Windows

No getting exception when using Step In for attached project. This is the screencast for the same: http://screencast.com/t/c8O7kBYeH