These two commits (as yet untested!!) should convert postgres.eclass and postgres-multi.eclass to handle builds and dependencies determinstically via USE flags rather than through detection of already installed postgres slots on disk.
Control of the dependency list in a multi-postgres package is purely through POSTGRES_COMPAT ; there may be a need for a second variable inside of postgres.eclass that can be used to intersect POSTGRES_COMPAT, so allow for easy dropping of no-longer-available postgres slots -- otherwise if a slot is dropped, all of the packages with said slot in POSTGRES_COMPAT will need to be edited. Note that there may be dynamic-dependency issues with either or both methods.
These two commits (as yet untested!!) should convert postgres.eclass and postgres-multi.eclass to handle builds and dependencies determinstically via USE flags rather than through detection of already installed postgres slots on disk.
Control of the dependency list in a multi-postgres package is purely through POSTGRES_COMPAT ; there may be a need for a second variable inside of postgres.eclass that can be used to intersect POSTGRES_COMPAT, so allow for easy dropping of no-longer-available postgres slots -- otherwise if a slot is dropped, all of the packages with said slot in POSTGRES_COMPAT will need to be edited. Note that there may be dynamic-dependency issues with either or both methods.