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Subject: [Bug tree-optimization/46562] New: CCP currently needs iteration for &a[i]
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46562

           Summary: CCP currently needs iteration for &a[i]
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: rguenth@gcc.gnu.org
        ReportedBy: rguenth@gcc.gnu.org


static int a[4];
int foo(void)
{
  int i = 1;
  int *p = &a[i];
  return *p;
}

compiled with the C++ FE (to yield an ARRAY_REF) shows that CCP needs
to iterate to figure out that p is a constant (and thus fold the read
from a[1]).