diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 697a161a97..ce85881caa 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2017-09-27  Tom Tromey  <tom@tromey.com>
+
+	* cli/cli-cmds.h (cd_command): Constify.
+	* cli/cli-cmds.c (cd_command): Constify.
+
 2017-09-27  Tom Tromey  <tom@tromey.com>
 
 	* thread.c (thread_name_command, thread_find_command): Constify.
diff --git a/gdb/cli/cli-cmds.c b/gdb/cli/cli-cmds.c
index c00994140f..dde67ee2b3 100644
--- a/gdb/cli/cli-cmds.c
+++ b/gdb/cli/cli-cmds.c
@@ -395,7 +395,7 @@ pwd_command (char *args, int from_tty)
 }
 
 void
-cd_command (char *dir, int from_tty)
+cd_command (const char *dir, int from_tty)
 {
   int len;
   /* Found something other than leading repetitions of "/..".  */
diff --git a/gdb/cli/cli-cmds.h b/gdb/cli/cli-cmds.h
index 1122a97b34..34d19f50c6 100644
--- a/gdb/cli/cli-cmds.h
+++ b/gdb/cli/cli-cmds.h
@@ -110,7 +110,7 @@ int is_complete_command (struct cmd_list_element *cmd);
 
 /* Exported to gdb/main.c */
 
-extern void cd_command (char *, int);
+extern void cd_command (const char *, int);
 
 /* Exported to gdb/top.c and gdb/main.c */