Mata library compatibility problem

Experimenting with two library files obtained from the same mata code in Stata 9.2 and 9.0.

Library compiled in 9.2 can be described in 9.2


Same library can't be described in 9.0 (this is ok, Stata 9.0 doesn't know anything about 9.2 code format, no forward compatibility).


Same library can be described in later version, here in 12.0 (backward compatibility is declared in Stata).



Library compiled in 9.0 can be described in 9.0:


Same library can't be described in 9.2


This is a problem. Stata should be backward compatible and recognize earlier library format. Same problem occurs in all subsequent versions of Stata.