Bug 13892 - Use of unassigned out parameter
Summary: Use of unassigned out parameter
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2013-08-09 14:35 UTC by Bryan Moulton
Modified: 2013-08-19 07:23 UTC (History)
2 users (show)

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

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Description Bryan Moulton 2013-08-09 14:35:13 UTC
In reference to case #41662

The following class compiles fine in Visual Studio, but compiles with the error "Use of unassigned out parameter" in XS.

using System;
using MonoTouch.Foundation;
using MonoTouch.CoreData;

public sealed class ChildManagedObjectContext : NSManagedObjectContext
	private readonly NSManagedObjectContext _mainManagedObjectContext;

	public ChildManagedObjectContext (NSManagedObjectContext mainManagedObjectContext)
		: base(NSManagedObjectContextConcurrencyType.PrivateQueue)
		ParentContext = mainManagedObjectContext;
		_mainManagedObjectContext = mainManagedObjectContext;

	public override bool Save (out NSError error)
		error = null;
		NSError saveError = null;
		var succeeded = false;

		PerformAndWait (() =>
			NSError baseSaveError;
			succeeded = base.Save (out baseSaveError);
			if (!succeeded) {
				saveError = baseSaveError;

		if (succeeded) {
			_mainManagedObjectContext.PerformAndWait (() =>
				NSError mainError;
				succeeded = _mainManagedObjectContext.Save (out mainError);

				if (!succeeded) {
					saveError = mainError;

		error = saveError;
		return succeeded;
Comment 1 Marek Safar 2013-08-19 07:23:22 UTC
Fixed in master