FPC keeps a typical building chain where release N is only guaranteed to build with release N-1. One can be lucky from time to time with point releases (x.y.n also buildable with x.y.n-1)
Note that the only binary that is really necessary from the older release to bootstrap is the compiler binary itself (ppc386 or ppcx64 for x86_64).
I don't know what the debian/ubuntu policies are, but in FreeBSD afaik this was avoided by having a separate port for the bootstrap compiler, which can be quicker and easier bumped than the main release.
FPC keeps a typical building chain where release N is only guaranteed to build with release N-1. One can be lucky from time to time with point releases (x.y.n also buildable with x.y.n-1)
Note that the only binary that is really necessary from the older release to bootstrap is the compiler binary itself (ppc386 or ppcx64 for x86_64).
I don't know what the debian/ubuntu policies are, but in FreeBSD afaik this was avoided by having a separate port for the bootstrap compiler, which can be quicker and easier bumped than the main release.