Bug 12361 - Yield return generates invalid IL code
Summary: Yield return generates invalid IL code
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2013-05-23 10:43 UTC by koczkatamas
Modified: 2013-05-28 05:15 UTC (History)
1 user (show)

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

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Description koczkatamas 2013-05-23 10:43:17 UTC
Tested on http://www.compileonline.com/compile_csharp_online.php.

using System;
using System.Linq;
using System.Collections.Generic;

public class Test
    public static void Main()
		var x = Test2();
        Console.WriteLine(x == null ? "null" : x.Count().ToString());
    public static IEnumerable<int> Test2(){
            yield return 5;            

Compiling the source code....
$mcs main.cs -out:demo.exe 2>&1
main.cs(15,13): warning CS0162: Unreachable code detected
Compilation succeeded - 1 warning(s)

Executing the program....
$mono demo.exe 
Unhandled Exception: System.InvalidProgramException: Invalid IL code in Test/c__Iterator0:MoveNext (): IL_0018: unused28  

  at System.Linq.Enumerable.Count[Int32] (IEnumerable`1 source) [0x00000] in :0 
  at Test.Main () [0x00000] in :0 
Comment 1 Marek Safar 2013-05-28 05:15:17 UTC
Fixed in master