1999-02-15 16:59 -0500  Zack Weinberg  <zack@midnite.ec.rhno.columbia.edu>
	* c-common.c (UNGETC [USE_CPPLIB=1]): Do nothing if c is EOF.
	* c-lex.c: Likewise.
	* cpplib.c (cpp_push_buffer, cpp_pop_buffer): Use a linked
	list in malloced memory for the buffer stack.
	(cpp_get_token): Don't pop the last buffer off the stack.
	Calls after CPP_EOF has been returned produce CPP_EOF with no
	state change.
	(cpp_finish): Pop last buffer here.
	(do_line): Don't free ip->last_nominal_fname if it is equal to
	ip->fname.
	(special_symbol): If a T_CONST is the empty string, push a
	single `@ ' escape instead.
	(macroexpand): Special symbol buffers have escapes too.
	* cpplib.h (struct cpp_buffer): Remove unused fields, add prev
	buffer pointer.
	(struct cpp_reader): Remove buffer_stack.  Add
	buffer_stack_depth.
	(CPP_PREV_BUFFER, CPP_NULL_BUFFER): Buffer stack is now a
	linked list.

From-SVN: r25218