This commit was generated by cvs2svn to compensate for changes in r174531,

which included commits to RCS files with non-trunk default branches.

contrib/gcc/fold-const.c

@@ -5661,6 +5661,9 @@ extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
             }
           break;
         }
+      /* If the constant is negative, we cannot simplify this.  */
+      if (tree_int_cst_sgn (c) == -1)
+	break;
       /* FALLTHROUGH */
     case NEGATE_EXPR:
       if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))