The two-state variables are in the vpiVariable category.

Add all the two-state variables (bit, byte, short, int and long) to
the vpiVariable category.

vvp/vpi_scope.cc

@@ -270,8 +270,13 @@ static int compare_types(int code, int type)
 	    return 1;
 
       if ( code == vpiVariables &&
-	     (type == vpiIntegerVar ||
-	      type == vpiTimeVar    ||
+	     (type == vpiIntegerVar  ||
+	      type == vpiBitVar      ||
+	      type == vpiByteVar     ||
+	      type == vpiShortIntVar ||
+	      type == vpiIntVar      ||
+	      type == vpiLongIntVar  ||
+	      type == vpiTimeVar     ||
 	      type == vpiRealVar))
 	    return 1;