Messages in this thread | | | Date | Mon, 8 Nov 2010 12:20:46 +0100 | Subject | Re: gcc 4.5.1 / as 2.20.51.0.11 miscompiling drivers/char/i8k.c ? | From | Richard Guenther <> |
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On Mon, Nov 8, 2010 at 12:20 PM, Andi Kleen <andi@firstfloor.org> wrote: > Richard Guenther <richard.guenther@gmail.com> writes: > >> On Mon, Nov 8, 2010 at 12:03 AM, Andi Kleen <andi@firstfloor.org> wrote: >>> Andreas Schwab <schwab@linux-m68k.org> 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@linux.intel.com -- Speaking for myself only. > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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