re PR c/53063 (encode group options in the .opt files)

re PR c/53063 (encode group options in the .opt files)

2012-10-16  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	PR c/53063
	PR c/40989
gcc/
	* optc-gen.awk: Handle new form of LangEnabledBy.
	* opts.c (set_Wstrict_aliasing): Declare here. Make static.
	* common.opt (Wstrict-aliasing=,Wstrict-overflow=): Do not use Init.
	* doc/options.texi (LangEnabledBy): Document new form.
	* flags.h (set_Wstrict_aliasing): Do not declare.
c-family/
	* c.opt (Wstrict-aliasing=,Wstrict-overflow=): Use LangEnabledBy.
	* c-opts.c (c_common_handle_option): Do not set them here. Add
	comment.
	(c_common_post_options): Likewise.
testsuite/
	* gcc.dg/Wstrict-overflow-24.c: New.

From-SVN: r192502