PR c/7652
gcc/cp/
	* call.c (add_builtin_candidate): Add gcc_fallthrough.
	* cxx-pretty-print.c (pp_cxx_unqualified_id): Likewise.
	* parser.c (cp_parser_skip_to_end_of_statement): Likewise.
	(cp_parser_cache_defarg): Likewise.
libcpp/
	* pch.c (write_macdef): Add CPP_FALLTHRU.

From-SVN: r239566