Andres Freund <andres@2ndquadrant.com> writes:
> Btw, I had wondered before if we shouldn't also add sizeof(long) to
> pg_control to catch cases where a database is copied between a LLP64
> (64bit windows) and an LP64 (nearly every other 64bit system) system. I
> have my doubts that we're completely clean about the size
> difference. Not to speak of extension datatypes.
I don't believe that this is necessary. It's certainly true that some
in-memory structures will be laid out differently, but not on-disk.
regards, tom lane