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Date: Wed, 25 Feb 2009 11:11:00 -0000
Subject: [Bug tree-optimization/39299]  New: wrong PTA for structure copies
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From: "rguenth at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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At -O2 -fno-tree-sra we compute y.p as pointing to nothing.  Which causes
the abort to trigger on alias-improvements branch.

struct X
{
  long l1;
  struct Y
  {
    long l2;
    int *p;
  } y;
};
int i;
int foo (struct X *x)
{
  struct Y y = x->y;
  *y.p = 0;
  i = 1;
  return *y.p;
}
extern void abort (void);
int main()
{
  struct X x;
  x.y.p = &i;
  if (foo(&x) != 1)
    abort ();
  return 0;
}


-- 
           Summary: wrong PTA for structure copies
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: wrong-code, alias
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rguenth at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39299