2010-05-05 Miguel de Icaza <miguel@novell.com>

	* class.cs (TypeContainer.DefineBaseTypes)
	(TypeContainer.CheckRecursiveDefinition): check for the iface not
	being null, as we could have failed resolution and crashed;
	Fixes #442144


svn path=/trunk/mcs/; revision=156759

mcs/errors/cs0246-21.cs

@@ -0,0 +1,22 @@
+// CS0246: The type or namespace name `IBase' could not be found. Are you missing a using directive or an assembly reference?
+// Line: 155555
+
+namespace Foo {
+        public interface IBase {
+                object X { get; }
+        }
+}
+
+public interface IDerived<T> : Foo.IBase {
+        T X { get; }
+}
+
+public class Test<T> {
+        public class Y : IDerived<T>, IBase
+        {
+                public T X { get { return default (T); } }
+                object Foo.IBase.X {
+                        get { return default (T); }
+                }
+        }
+}

mcs/mcs/ChangeLog

@@ -1,5 +1,10 @@
 2010-05-05  Miguel de Icaza  <miguel@novell.com>
 
+	* class.cs (TypeContainer.DefineBaseTypes)
+	(TypeContainer.CheckRecursiveDefinition): check for the iface not
+	being null, as we could have failed resolution and crashed;
+	Fixes #442144
+
 	* cs-parser.jay: Productions to catch common mistakes when other
 	punctuation operators are used instead of comma.   Fixes 571702	
 

mcs/mcs/class.cs

@@ -1063,6 +1063,10 @@ bool DefineBaseTypes ()
 
 			if (iface_exprs != null) {
 				foreach (TypeExpr iface in iface_exprs) {
+					// Prevents a crash, the interface might not have been resolved: 442144
+					if (iface == null)
+						continue;
+
 					var iface_type = iface.Type;
 
 					if (!spec.AddInterface (iface_type))
@@ -1353,6 +1357,9 @@ TypeSpec CheckRecursiveDefinition (TypeContainer tc)
 
 			if (iface_exprs != null) {
 				foreach (TypeExpr iface in iface_exprs) {
+					// the interface might not have been resolved, prevents a crash, see #442144
+					if (iface == null)
+						continue;
 					var ptc = iface.Type.MemberDefinition as Interface;
 					if (ptc != null && ptc.CheckRecursiveDefinition (this) != null)
 						return iface.Type;