--- a/dmd/TypeEnum.d	Sat Sep 11 13:03:39 2010 +0100
+++ b/dmd/TypeEnum.d	Mon Sep 13 22:19:42 2010 +0100
@@ -189,11 +189,20 @@
 	
     override MATCH constConv(Type to)
 	{
-		assert(false);
+        if (equals(to))
+	        return MATCHexact;
+        if (ty == to.ty && sym == (cast(TypeEnum)to).sym &&
+	        MODimplicitConv(mod, to.mod))
+	        return MATCHconst;
+        return MATCHnomatch;
 	}
 	
     override Type toBasetype()
 	{
+        if (sym.scope_)
+        {
+    	    sym.semantic(null);	// attempt to resolve forward reference
+        }
 		if (!sym.memtype)
 		{
 			debug writef("2: ");