[Bug c/41630] [4.3/4.4 Regression] Optimization error on vectors of uint64_t

[rguenth at gcc dot gnu dot org]

------- Comment #4 from rguenth at gcc dot gnu dot org  2009-10-08 14:52 -------
Simplified testcase, fails at -O1.  Likely an aliasing issue, but I didn't
yet fully investigate (nor ruled out a non-conforming testcase - though
TBAA is out of the question here):

typedef unsigned long obj[1];
extern void abort (void);
static void test_level2(obj X[])
{
    if (*X[0] != 12345
        || *X[1] != 67890)
      abort ();
}
static void test_level1(obj x0, obj x1)
{
    obj X[2];

    X[0][0] = x0[0];
    X[1][0] = x1[0];

    if (*x0 != 12345
        || *x1 != 67890)
      abort ();
    test_level2 (X);
}
int main()
{
    obj X[2];
    *X[0] = 12345;
    *X[1] = 67890;
    test_level1(X[0], X[1]);
    return 0;
}


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
           Keywords|                            |wrong-code
      Known to fail|                            |4.3.4 4.4.1
      Known to work|                            |4.2.4 4.5.0
   Last reconfirmed|0000-00-00 00:00:00         |2009-10-08 14:52:06
               date|                            |
            Summary|Optimization error on       |[4.3/4.4 Regression]
                   |vectors of uint64_t         |Optimization error on
                   |                            |vectors of uint64_t


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41630