[RFC] strcpy optimizations

[Paul Eggert]

On 01/29/13 13:53, Ondřej Bílka wrote:
> I wanted to use it only to bytes which change.

Sorry, I don't follow.

> There is problem with code like this:
> struct foo {
>   long x;
>   char y[8];
>   long z;
> }
> foo f;
> 
> With f.x++;              in first thread
> With f.z++;              in second thread
> and  strcpy (f.y, "abc") in third thread.

The behavior of strcpy is undefined in that case.
So strcpy can do whatever it likes, and
that includes using the pblendvb instruction.