[Bug rtl-optimization/69482] Writing through pointers to volatile not always preserved

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69482

--- Comment #3 from rguenther at suse dot de <rguenther at suse dot de> ---
On Tue, 26 Jan 2016, wipedout at yandex dot ru wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69482
> 
> wipedout at yandex dot ru changed:
> 
>            What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                  CC|                            |wipedout at yandex dot ru
> 
> --- Comment #2 from wipedout at yandex dot ru ---
> I also found that this code
> 
>   int x[4];
>   memset_s(x, 6);
> 
> also emits no writes. Is this because of undefined behavior or is it for any
> other reason?

Well, x is not used so all the code is dead (independent on whether
the memset invokes undefined behavior).