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Re: [tree-ssa] Avoid nondeterminism in tree-ssanames
> Jan Hubicka <firstname.lastname@example.org> writes:
> > Hi,
> > I've run into problem that tree-ssanames in combination with garbage
> > collector may produce non-deterministic results. The problem is that
> > garbage collector invoked form the middle of SSA compilation path (not
> > done in official tree) zaps the free list of nodes.
> Can you try to work out why zapping a freelist should produce
> different results? It shouldn't.
> If you find that bug, then this patch is unnecessary.
It is not bug and this patch also saves memory.
It is same as with RTL - if you change register numbers, you change
hashtables and you change decisions in some corner cases. This is IMO
OK and it is very wrong to have different SSA_VERSIONs depending on GGC
> - Geoffrey Keating <email@example.com>