gdb/

gdb/
	Provide $ddir substitution for --with-auto-load-safe-path.
	* NEWS (--with-auto-load-safe-path, --without-auto-load-safe-path): New
	entries.
	* auto-load.c: Include observer.h.
	(auto_load_safe_path_vec_update): Call substitute_path_component for
	each component.  New variable ddir_subst.
	(auto_load_gdb_datadir_changed): New function.
	(set_auto_load_safe_path): Rename DEFAULT_AUTO_LOAD_SAFE_PATH to
	AUTO_LOAD_SAFE_PATH.  New comment.
	(_initialize_auto_load): Rename DEFAULT_AUTO_LOAD_SAFE_PATH to
	AUTO_LOAD_SAFE_PATH.  Install auto_load_gdb_datadir_changed.
	* config.in: Regenerate.
	* configure: Regenerate.
	* configure.ac (--auto-load-safe-path): Rename
	DEFAULT_AUTO_LOAD_SAFE_PATH to AUTO_LOAD_SAFE_PATH.  Default to
	GDB_DATADIR/auto-load.
	* defs.h (substitute_path_component): New declaration.
	* top.c: Include observer.h.
	(set_gdb_datadir): New function.
	(init_main): Install it for "set data-directory".
	* utils.c (substitute_path_component): New function.

gdb/doc/
	Provide $ddir substitution for --with-auto-load-safe-path.
	* gdb.texinfo (Auto-loading): Replace /usr/local by $ddir/auto-load.
	(Auto-loading safe path): Likewise.  Mention the default value,
	$ddir substitution, --with-auto-load-safe-path and
	--without-auto-load-safe-path.
	* observer.texi (gdb_datadir_changed): New.