Makefile.am: Add makedepend.

Makefile.am: Add makedepend.

libcpp:
	* Makefile.am: Add makedepend.
	* Makefile.in, aclocal.m4: Regenerate.
	* charset.c: Insert a space to avoid a warning.
	* directives.c: Include mkdeps.h.
	(_cpp_handle_directive): Reenable macro expander if appropriate.
	(undefine_macros): Inline body of _cpp_free_definition for speed.
	Do not call undef callback or _cpp_warn_if_unused_macro.
	(cpp_get_deps): New interface.
	* files.c (search_cache): Add pfile argument.  Check for file
	that would be found by "" or <> search here...
	(_cpp_find_file): ...not here.  Correct recorded start_dir of
	files found by directory-of-current-file search that would be
	found by "" or <> search.
	* init.c (cpp_add_dependency_target): Delete.
	* internal.h (struct lexer_state): Add discarding_output flag.
	* lex.c (lex_identifier): Compute hash function while scanning.
	* macro.c (cpp_scan_nooutput): Disable macro expansion outside
	directives.
	* makedepend.c: New file.
	* mkdeps.c (struct deps): Add vpath vector.
	(apply_vpath, deps_add_vpath): New function.
	(deps_free): Free vpath vector.
	(deps_add_dep, deps_add_target): Use apply_vpath.
	* symtab.c (calc_hash): Use HT_HASHSTEP and HT_FINISH.
	(ht_lookup_with_hash): New function.
	* cpplib.h, mkdeps.h: Update prototypes.
	* symtab.h: Update prototypes.
	(HT_HASHSTEP, HT_FINISH): New macros.

gcc:
	* Makefile.in (MKDEPS_H): New shorthand.
	(c-opts.o): Update dependencies.
	* c-opts.c: Include mkdeps.h.
	(handle_deferred_opts): Use cpp_get_deps and deps_add_target,
	not cpp_add_dependency_target.

From-SVN: r82654