Re: __attribute__ for non-gcc compilers

On Wed, Jan 14, 2015 at 5:29 PM, Andres Freund <andres(at)2ndquadrant(dot)com> wrote:
> I think it's better than the alternatives:
>
> a) Don't support 64bit atomics on any 32bit platform. I think that'd be
> sad because there's some places that could greatly benefit from being
> able to read/store/manipulate e.g. LSNs atomically.
> b) Double the size of 64bit atomics on 32bit platforms, and add
> TYPEALIGN() to every access inside the atomics implementation.
> c) Require 64 atomics to be aligned appropriately manually in every
> place they're embedded. I think that's completely impractical.
>
> The only viable one imo is a)

I can't really fault that reasoning, but if __attribute__((align))
only works on some platforms, then you've got silent, subtle breakage
on the ones where it doesn't.

--
Robert Haas
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