[Bug tree-optimization/30911] New: VRP fails to eliminate range checks in Ada code

["baldrick at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

All of the range checks can in theory be eliminated, except
for the first one (a call to __gnat_rcheck_04, unlike the
others which are calls to __gnat_rcheck_04), but they are
not:

$ gcc -c -O2 -fdump-tree-all j.ads
$ grep __gnat_rcheck_12 j.ads.118t.final_cleanup
  __gnat_rcheck_12 ("join_equal.adb", 14);
  __gnat_rcheck_12 ("join_equal.adb", 14);
  __gnat_rcheck_12 ("join_equal.adb", 29);
  __gnat_rcheck_12 ("join_equal.adb", 29);
  __gnat_rcheck_12 ("join_equal.adb", 39);
  __gnat_rcheck_12 ("join_equal.adb", 39);


-- 
           Summary: VRP fails to eliminate range checks in Ada code
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: baldrick at gcc dot gnu dot org
  GCC host triplet: i486-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30911