[Bug ipa/91596] IPA cdtor merging should preserve link file ordering

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91596

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #2)
> Previously we have decided this to be invalid.  I think it is a mistake to
> consider us to do this really.

True, but when it's easy then from a QOI perspective I'd rather have
-flto preserve -fno-lto behavior as much as possible.

I realize we cannot have this fully because partitioning gets in the way
unless we forcefully partition all global ctors/dtors into a single
partition (OTOH it's probably pretty random in which partition they
end up since they are not actually called - do they end up where
refs to the referred to vars end up?  probably more where called
ctors/dtors end up, but we'd ship their body for inlining multiple
times anyway).