* c-parse.in (_yylex): Use _cpp_backup_tokens.

	* c-parse.in (_yylex): Use _cpp_backup_tokens.
	* cpphash.h (struct tokenrun): Add prev.
	(struct lexer_state): Remove bol.
	(struct cpp_reader): Remove old lookahead stuff, add lookaheads.
	(_cpp_free_lookaheads, _cpp_release_lookahead, _cpp_push_token)
	: Remove.
	* cppinit.c (cpp_create_reader): Don't set bol.
	(cpp_destroy): Don't free lookaheads.
	* cpplex.c (lex_directive): Remove.
	(next_tokenrun): Update.
	(_cpp_lex_token): Clean up logic.
	(lex_token): Update to return a pointer to lexed token, since it
	can move to the start of the buffer.  Simpify newline handling.
	* cpplib.c (SEEN_EOL): Update.
	(skip_rest_of_line): Remove lookahead stuff.
	(end_directive): Line numbers are already incremented.  Revert
	to start of lexed token buffer if we can.
	(_cpp_handle_directive, do_pragma, do_pragma_dependency,
	parse_answer): Use _cpp_backup_tokens.
	(run_directive, cpp_pop_buffer): Don't set bol, set saved_flags
	instead.  Don't check for EOL.
	(do_include_common, do_line, do_pragma_system_header): Use
	skip_rest_of_line.
	* cpplib.h (BOL, _cpp_backup_tokens): New.
	* cppmacro.c (save_lookahead_token, take_lookahead_token,
	alloc_lookahead, free_lookahead, _cpp_free_lookaheads,
	cpp_start_lookahead, cpp_stop_lookahead, _cpp_push_token): Remove.
	(builtin_macro): Don't use cpp_get_line.
	(cpp_get_line): Short term kludge.
	(parse_arg): Handle directives in arguments here.  Back up when
	appropriate.  Store EOF at end of argument list.
	(funlike_invocation_p): Use _cpp_backup_tokens.
	(push_arg_context): Account for EOF at end of list.
	(cpp_get_token): Remove lookahead stuff.  Update.

	* gcc.dg/cpp/directiv.c: Update.
	* gcc.dg/cpp/undef1.c: Update.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@45582 138bc75d-0d04-0410-961f-82ee72b054a4