common.opt (flag_stack_check): New Variable entry.

	* common.opt (flag_stack_check): New Variable entry.
	(fcompare-debug-second): Use Var.
	* flags.h (flag_compare_debug, flag_stack_check): Remove.
	* opts.c (flag_compare_debug): Remove.
	(common_handle_option): Don't handle OPT_fcompare_debug_second.
	Set opts->x_flag_stack_check for OPT_fstack_check_.
	* toplev.c (flag_stack_check): Remove.

ada:
	* gcc-interface/misc.c (flag_compare_debug, flag_stack_check):
	Undefine as macros then define as variables.
	(gnat_post_options): Set variables from global_options.

From-SVN: r167331