A system with one cluster preceded by the keyword "all" in the Ace
file is compiled, where the cluster does not exist.  The compiler
correctly reports a VD01 error (nonexistent cluster path in Ace file).
Then the cluster is created with one sub-cluster `sub' which contains
the root class.  When compilation is resumed, the compiler reports a
bogus VD30 error.

Discovered in release 5.4.0403.