diff --git a/ICSharpCode.Decompiler/Ast/AstMethodBodyBuilder.cs b/ICSharpCode.Decompiler/Ast/AstMethodBodyBuilder.cs
index d1972056d..53c0d3457 100644
--- a/ICSharpCode.Decompiler/Ast/AstMethodBodyBuilder.cs
+++ b/ICSharpCode.Decompiler/Ast/AstMethodBodyBuilder.cs
@@ -598,7 +598,7 @@ namespace ICSharpCode.Decompiler.Ast
 							};
 						}
 					}
-				} else if (cecilMethodDef.Name == "Invoke" && cecilMethodDef.DeclaringType.BaseType.FullName == "System.MulticastDelegate") {
+				} else if (cecilMethodDef.Name == "Invoke" && cecilMethodDef.DeclaringType.BaseType != null && cecilMethodDef.DeclaringType.BaseType.FullName == "System.MulticastDelegate") {
 					AdjustArgumentsForMethodCall(cecilMethod, methodArgs);
 					return target.Invoke(methodArgs);
 				}