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
diff --git a/libcpp/symtab.c b/libcpp/symtab.c
index c80dfa2..9b2e0f1 100644
--- a/libcpp/symtab.c
+++ b/libcpp/symtab.c
@@ -41,13 +41,11 @@
 {
   size_t n = len;
   unsigned int r = 0;
-#define HASHSTEP(r, c) ((r) * 67 + ((c) - 113));
 
   while (n--)
-    r = HASHSTEP (r, *str++);
+    r = HT_HASHSTEP (r, *str++);
 
-  return r + len;
-#undef HASHSTEP
+  return HT_HASHFINISH (r, len);
 }
 
 /* Initialize an identifier hashtable.  */
@@ -96,7 +94,15 @@
 ht_lookup (hash_table *table, const unsigned char *str, size_t len,
 	   enum ht_lookup_option insert)
 {
-  unsigned int hash = calc_hash (str, len);
+  return ht_lookup_with_hash (table, str, len, calc_hash (str, len),
+			      insert);
+}
+
+hashnode
+ht_lookup_with_hash (hash_table *table, const unsigned char *str,
+		     size_t len, unsigned int hash,
+		     enum ht_lookup_option insert)
+{
   unsigned int hash2;
   unsigned int index;
   size_t sizemask;