[Bug tree-optimization/60098] New: DSE fails to DSE errno settings

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60098

            Bug ID: 60098
           Summary: DSE fails to DSE errno settings
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: rguenth at gcc dot gnu.org
          Reporter: rguenth at gcc dot gnu.org

void *foo (int *p)
{
  void *q;
  *p = 0;
  q = __builtin_malloc (4);
  *p = 0;
  return q;
}

the first *p = 0 store is dead.