[Bug fortran/54426] [4.8 Regression] FAIL: gfortran.dg/common_6.f90 -O (internal compiler error) on powerpc-apple-darwin9

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54426

--- Comment #2 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2012-08-31 
12:21:59 UTC ---
Following Tobias' suggestion on IRC, the patch

--- /opt/gcc/work/gcc/fortran/symbol.c    2012-08-28 01:14:39.000000000 +0200
+++ /opt/gcc/rel_work/gcc/fortran/symbol.c    2012-08-30 23:00:09.000000000
+0200
@@ -2890,6 +2890,7 @@ gfc_undo_symbols (void)
          needs to be removed to stop the resolver looking
          for a (possibly) dead symbol.  */

+          p->common_block->refs--;
           if (p->common_block->head == p)
             p->common_block->head = p->common_next;
           else

fixes the PR on powerpc-apple-darwin9 without regression.