Bug 2083 - System.InvalidProgramException: Invalid IL code
Summary: System.InvalidProgramException: Invalid IL code
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2011-11-17 19:47 UTC by Andrew Young
Modified: 2011-11-23 13:43 UTC (History)
1 user (show)

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

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Description Andrew Young 2011-11-17 19:47:53 UTC
Somehow I was able to get the compiler to compile this code snippet. Notice the "var groups = notificationObject.Data.Items.ForEach()" line in the middle. ForEach() returns void. You shouldn't be able to set a variable to void.

When executed at runtime it errors out with an InvalidProgramException.

_allGroups = new List<Group>();
_groupsCacheObserver = NSNotificationCenter.DefaultCenter.AddObserver(CacheableUserGroups.NotificationKey, 
(notification) => {

  var notificationObject = (NotificationObject<Page<UserGroup>>)notification.Object;
  var groups = notificationObject.Data.Items.ForEach(g => _allGroups.Add(new Group() { Id = g.Id.ToString(), Title = g.Name }));
  if(callback != null)

I have a sample project but I can only replicate it in our closed sourced MonoTouch project.
Comment 2 Marek Safar 2011-11-23 13:43:33 UTC
Fixed in master.

Thanks for the bug report.