diff --git a/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/CSharp/CSharpAmbience.cs b/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/CSharp/CSharpAmbience.cs
index 8b6c30ab79..d295c7f050 100644
--- a/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/CSharp/CSharpAmbience.cs
+++ b/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/CSharp/CSharpAmbience.cs
@@ -534,6 +534,8 @@ namespace ICSharpCode.SharpDevelop.Dom.CSharp
 		
 		static IReturnType GetElementType(IReturnType potentialArrayType)
 		{
+			if (potentialArrayType == null)
+				return null;
 			ArrayReturnType result;
 			while ((result = potentialArrayType.CastToArrayReturnType()) != null) {
 				potentialArrayType = result.ArrayElementType;
diff --git a/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/VBNet/VBNetAmbience.cs b/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/VBNet/VBNetAmbience.cs
index b5502c139d..0fc70994e9 100644
--- a/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/VBNet/VBNetAmbience.cs
+++ b/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/VBNet/VBNetAmbience.cs
@@ -552,6 +552,8 @@ namespace ICSharpCode.SharpDevelop.Dom.VBNet
 		
 		static IReturnType GetElementType(IReturnType potentialArrayType)
 		{
+			if (potentialArrayType == null)
+				return null;
 			ArrayReturnType result;
 			while ((result = potentialArrayType.CastToArrayReturnType()) != null) {
 				potentialArrayType = result.ArrayElementType;