[Bug c/108880] [11/12/13 Regression] slow compilation with "-fsanitize=undefined"

[mpolacek at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108880

--- Comment #10 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Another simple patch is

--- a/gcc/c-family/c-gimplify.cc
+++ b/gcc/c-family/c-gimplify.cc
@@ -516,7 +516,7 @@ c_genericize_control_stmt (tree *stmt_p, int
*walk_subtrees, void *data,
          tree t = tsi_stmt (i);
          if (TREE_CODE (t) != DEBUG_BEGIN_STMT && nondebug_stmts < 2)
        nondebug_stmts++;
-         walk_tree_1 (tsi_stmt_ptr (i), func, data, NULL, lh);
+         walk_tree_without_duplicates_1 (tsi_stmt_ptr (i), func, data, lh);
          if (TREE_CODE (t) != DEBUG_BEGIN_STMT
          && (nondebug_stmts > 1 || TREE_SIDE_EFFECTS (tsi_stmt (i))))
        clear_side_effects = false;