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

[Jeff Law]

On 11/15/10 15:07, Richard Guenther wrote:
> On Mon, Nov 15, 2010 at 7:45 PM, Jeff Law<law@xxxxxxxxxx>  wrote:
> > On 11/08/10 03:49, Richard Guenther wrote:
> > > 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.
> > A memory clobber should clobber anything in memory, including autos in
> > memory; if it doesn't, then that seems like a major problem.  I'd like to
> > see the rationale behind not clobbering autos in memory.
> Non-address taken automatic storage.  (note that we don't excercise this
> in optimization yet)
If the address of the auto isn't taken, then why is the object in memory 
to begin with (with the obvious exception for aggregates).

Jeff
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