* c-decl.c (init_decl_processing):
	 Don't call start_identifier_warnings.
	* flags.h (warn_id_clash, id_clash_len): Remove.
	* stringpool.c: Don't include flags.h.
	(scan_for_clashes, do_identifier_warnings,
	start_identifier_warnings): Remove.
	* toplev.c (warn_id_clash, id_clash_len): Remove.
	(display_help): Don't document -Wid-clash.
	(decode_W_option): Print warning on -Wid-clash.
	* tree.h (start_identifier_warnings): Remove.
	* invoke.texi: Remove documentation of -Wid-clash.

From-SVN: r42665