A class inherits different versions of a routine with the same name
and signature from different parents, but redefines the feature.  The
flatshort form looks as expected, with all preconditions of redefined
versions of the feature in the expected order.  But when the system is
executed, the preconditions are checked in a different order than that
indicated by the flatshort form.  Same problem for postconditions.

Discovered in Release 3.2.3b.