[Bug tree-optimization/59124] [4.9/5/6 Regression] Wrong warnings "array subscript is above array bounds"

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59124

--- Comment #39 from Patrick Palka <ppalka at gcc dot gnu.org> ---
(In reply to Domani Hannes from comment #37)
> With the new patch there is still a warning with this example:
> =============== 8< ===============
> int f(void);
> 
> int test(void)
> {
>   int baz[4];
>   int q = 0;
>   int d, i, j, sum;
> 
>   for (i = 0; i < 2; i++)
>   {
>     d = f();
> 
>     if (d == 3)
>     {
>       baz[q] = d;
>       q++;
>       if (q == 4) break;
>     }
>   }
> 
>   sum = 0;
>   for (i = 0; i < q; i++)
>   {
>     for (j = i + 1; j < q; j++)
>     {
>       sum += baz[j];
>     }
>   }
> 
>   return (sum);
> }
> =============== >8 ===============
> $ gcc -O3 -Wall -S q.c
> q.c: In function 'test':
> q.c:27:17: warning: array subscript is above array bounds [-Warray-bounds]
>        sum += baz[j];
>                  ^

Thanks, I'll check it out.  Seems to be a regression from 4.7 as well.