On Tue, Jun 6, 2017 at 2:24 PM, Andres Freund <andres@anarazel.de> wrote:
> Don't think it's actually clear that errno is an integer - might very
> well be just a sig_atomic_t, which can contain values up to like 127 or
> so. I think the bigger point Tom was making is that we actually know
> an int4 is safe - otherwise we'd have crashed and burned a long time ago
> - but that that might be different for *smaller* datatypes because
> $platform doesn't really do smaller writes atomically (turning them into
> read-or-write operations either in microcode or assembly).
Oh, right, I remember hearing about that issue before, but it had
slipped my mind completely.
> Alpha,
> s390, pa-risc appear to have such behaviour cross-cpu - although that
> doesn't necessarily imply the same is true for handlers as well.
Hmm, OK. We've already decided Alpha is safely dead, but s390 and
pa-risc are ostensibly not dead.
--
Robert Haas
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