Re: gcc 4.5.1 / as 2.20.51.0.11 miscompiling drivers/char/i8k.c ?

[Richard Guenther]

On Mon, Nov 8, 2010 at 12:20 PM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:
> Richard Guenther <richard.guenther@xxxxxxxxx> writes:
>
>> On Mon, Nov 8, 2010 at 12:03 AM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:
>>> Andreas Schwab <schwab@xxxxxxxxxxxxxx> writes:
>>>>
>>>> The asm fails to mention that it modifies *regs.
>>>
>>> It has a memory clobber, that should be enough, no?
>>
>> No.  A memory clobber does not cover automatic storage.
>
> That's a separate problem.
>
>> Btw, I can't see a testcase anywhere so I just assume Andreas got
>> it right as usual.
>
> An asm with live inputs and outputs should never be optimized
> way. If 4.5.1 started doing that it's seriously broken.

Please provide a testcase, such asms can be optimized if the
outputs are dead.

Richard.

> -Andi
>
> --
> ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
>
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