Added xx and xxsubtype modules, for completeness and because xxsubtype is used by the test suite.
diff --git a/Mac/scripts/fullbuild.py b/Mac/scripts/fullbuild.py
index 8954739..fa19f79 100644
--- a/Mac/scripts/fullbuild.py
+++ b/Mac/scripts/fullbuild.py
@@ -239,6 +239,8 @@
 	(":Mac:Build:_weakref.mcp", "_weakref.ppc"),
 	(":Mac:Build:_symtable.mcp", "_symtable.ppc"),
 	(":Mac:Build:_testcapi.mcp", "_testcapi.ppc"),
+	(":Mac:Build:xx.mcp", "xx.ppc"),
+	(":Mac:Build:xxsubtype.mcp", "xxsubtype.ppc"),
 	(":Mac:Build:pyexpat.mcp", "pyexpat.ppc"),
 	(":Mac:Build:calldll.mcp", "calldll.ppc"),
 	(":Mac:Build:ctb.mcp", "ctb.ppc"),
@@ -279,6 +281,8 @@
 	(":Mac:Build:_weakref.carbon.mcp", "_weakref.carbon"),
 	(":Mac:Build:_symtable.carbon.mcp", "_symtable.carbon"),
 	(":Mac:Build:_testcapi.carbon.mcp", "_testcapi.carbon"),
+	(":Mac:Build:xx.carbon.mcp", "xx.carbon"),
+	(":Mac:Build:xxsubtype.carbon.mcp", "xxsubtype.carbon"),
 	(":Mac:Build:pyexpat.carbon.mcp", "pyexpat.carbon"),
 	(":Mac:Build:calldll.carbon.mcp", "calldll.carbon"),
 	(":Mac:Build:gdbm.carbon.mcp", "gdbm.carbon"),