[Bug c/14065] New: tree-ssa generates duplicate definision of invisible sybmbol forward defined

["fjahanian at apple dot com" <gcc-bugzilla at gcc dot gnu dot org>]

This bug was also uncovered building gap of the spec benchmark with tree-ssa. In the
following trivial test case, tree-ssa gcc produces two definition of the locally declaraed extern
which is later defined. Compile with -O2.

/* Bug in tree-ssa, tested on Apple, darwin, ppc. Compile with O2:

mygcct5o -O2 prxxx.c
/var/tmp//ccZZXOy5.s:8:FATAL:Symbol _CPN already defined.

*/


void collect()
{
    extern long         CPN;
}
long         CPN=1;

-- 
           Summary: tree-ssa generates duplicate definision of invisible
                    sybmbol forward defined
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: fjahanian at apple dot com
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: powerpc-apple-darwin7.0.0
GCC target triplet: powerpc-apple-darwin7.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14065