Added an unsupported type node to the AST.

src/AST/ASTVisitor.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 
 namespace CppSharp.AST
 {
@@ -278,6 +279,14 @@ namespace CppSharp.AST
             return true;
         }
 
+        public bool VisitUnsupportedType(UnsupportedType type, TypeQualifiers quals)
+        {
+            if (!VisitType(type, quals))
+                return false;
+
+            return true;
+        }
+
         #endregion
 
         #region Decl Visitors

src/AST/CppTypePrinter.cs

@@ -229,6 +229,11 @@ namespace CppSharp.AST
             throw new NotImplementedException(string.Format("Unhandled .NET type: {0}", type.Type));
         }
 
+        public string VisitUnsupportedType(UnsupportedType type, TypeQualifiers quals)
+        {
+            return string.Empty;
+        }
+
         public string VisitPrimitiveType(PrimitiveType type, TypeQualifiers quals)
         {
             throw new System.NotImplementedException();

src/AST/Type.cs

@@ -1054,6 +1054,30 @@ namespace CppSharp.AST
         }
     }
 
+    public class UnsupportedType : Type
+    {
+        public UnsupportedType()
+        {
+        }
+
+        public UnsupportedType(UnsupportedType type)
+            : base(type)
+        {
+        }
+
+        public string Description;
+
+        public override T Visit<T>(ITypeVisitor<T> visitor, TypeQualifiers quals = new TypeQualifiers())
+        {
+            return visitor.VisitUnsupportedType(this, quals);
+        }
+
+        public override object Clone()
+        {
+            return new UnsupportedType(this);
+        }
+    }
+
     #region Primitives
 
     /// <summary>
@@ -1185,5 +1209,6 @@ namespace CppSharp.AST
         T VisitUnaryTransformType(UnaryTransformType unaryTransformType, TypeQualifiers quals);
         T VisitVectorType(VectorType vectorType, TypeQualifiers quals);
         T VisitCILType(CILType type, TypeQualifiers quals);
+        T VisitUnsupportedType(UnsupportedType type, TypeQualifiers quals);
     }
 }

src/Generator/Generators/CLI/CLITypePrinter.cs

@@ -340,6 +340,11 @@ namespace CppSharp.Generators.CLI
             return VisitPrimitiveType(type);
         }
 
+        public string VisitUnsupportedType(UnsupportedType type, TypeQualifiers quals)
+        {
+            throw new NotImplementedException();
+        }
+
         public string VisitDeclaration(Declaration decl, TypeQualifiers quals)
         {
             return VisitDeclaration(decl);

src/Generator/Generators/CSharp/CSharpTypePrinter.cs

@@ -842,6 +842,11 @@ namespace CppSharp.Generators.CSharp
             throw new NotImplementedException();
         }
 
+        public CSharpTypePrinterResult VisitUnsupportedType(UnsupportedType type, TypeQualifiers quals)
+        {
+            throw new NotImplementedException();
+        }
+
         public CSharpTypePrinterResult VisitFunctionTemplateSpecializationDecl(FunctionTemplateSpecialization specialization)
         {
             throw new NotImplementedException();

src/Generator/Passes/CheckVirtualOverrideReturnCovariance.cs

@@ -186,6 +186,11 @@ namespace CppSharp.Passes
             return false;
         }
 
+        public bool VisitUnsupportedType(UnsupportedType type, TypeQualifiers quals)
+        {
+            return false;
+        }
+
         public bool VisitDeclaration(Declaration decl)
         {
             return false;