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SubjectRe: [PATCH 1/1] X86: use explicit register name for get/put_user
On 12/07/2009 07:35 PM, H. Peter Anvin wrote:
> On 12/07/2009 04:37 AM, Jiri Slaby wrote:
>> In the document they write only about the "same location" occupied by in
>> and out, nothing is said about size (and hence I think we cannot
>> mismatch size of operands). And I couldn't find any other
>> restrictions/documentation about inline assembly, hence the patch,
>> because nothing assured me this cannot change in the future.
>
> There is almost no documentation at all; some of the little
> documentation there is is in comments in the source code. To a first
> order of approximation, asm() is defined by behavior, not by a written
> spec. Trying to play language lawyer with the little bit that is
> written down is pointless -- the gcc people have been more than happy to
> break asm() between releases regardless of what is and is not written down.

Ok, thanks for the explanation.

--
js


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