[Bug middle-end/44612] -flto -fwhole-program: Never read variable not optimized away

[burnus at gcc dot gnu dot org]

------- Comment #4 from burnus at gcc dot gnu dot org  2010-06-22 12:26 -------
(In reply to comment #2)
> Your testcase doesn't build:
> REAL,contiguous :: a(:,:,:,:)
>      1
> Error: Invalid character in name at (1)

If you want to test it with other compilers than the latest trunk, you can
simply take out the "contiguous" - though, as Jakub mentioned, it should build
with the latest GCC trunk builds. 

 * * *


C test case:

$ gcc -flto -fwhole-program -O3 -std=c99 test.c && time ./a.out
Start
Done

real    0m0.699s
user    0m0.676s
sys     0m0.004s


#include <stdio.h>
#define SIZE 40000

void s4 (float *restrict a)
{
  (void) __builtin_memset ((void *) a, 0, sizeof(float)*SIZE);
}


int main ()
{
  static float a[SIZE];
  int i;
  printf("Start\n");
  for (i = 0; i < SIZE; i++)
    s4 (a);
  printf("Done\n");
  return 0;
}


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2010-06-22 12:26:35
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44612