Re: bug in check for stack growth direction in _AC_LIBOBJ_ALLOCA

[Andrew W. Nosenko]

On Mon, Jun 20, 2011 at 09:50, Paul Eggert <address@hidden> wrote:
> On 06/19/11 23:35, Ralf Wildenhues wrote:
>> If you don't use volatile, the compiler is pretty much free to give you
>> whatever answer it likes today.
>
> It's true that the test relies on undefined behavior, and so the
> compiler is free to do whatever it wants, but I don't see how
> adding "volatile" helps, for this particular test.  Whatever reasoning
> the compiler can do without "volatile", it can also do with "volatile",
> for this test.

I just marked a volatile the underlying char instead of the pointer.
I will check the right (as I think) markup and send the result in 3-4 hours.

>
> (I have more confidence in the revised test, because this
> time I actually ran it on an x86-64 host with GCC 4.6.0.  :-)
>
>



-- 
Andrew W. Nosenko <address@hidden>