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SubjectRe: [PATCH] make atomic_t volatile on all architectures


On Sun, 12 Aug 2007, Martin Schwidefsky wrote:
>
> The duplication "=m" and "m" with the same constraint is rather
> annoying.

It's not only annoying, it causes gcc to generate bad code too. At least
certain versions of gcc will generate the address *twice*, even if there
is obviously only one address used.

If you have problems with "+m", you are often actually better off using
just "m" and then adding a memory clobber. But that has other code
generation downsides.

Linus
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