diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 9afbb776309..077fa4a9ae2 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2017-09-27  Tom Tromey  <tom@tromey.com>
+
+	* ada-tasks.c (task_command_1, task_command): Constify.
+
 2017-09-27  Tom Tromey  <tom@tromey.com>
 
 	* symtab.c (maintenance_print_symbol_cache)
diff --git a/gdb/ada-tasks.c b/gdb/ada-tasks.c
index 19f74ddac71..e0070d5b9ab 100644
--- a/gdb/ada-tasks.c
+++ b/gdb/ada-tasks.c
@@ -1265,7 +1265,7 @@ display_current_task_id (void)
    that task.  Print an error message if the task switch failed.  */
 
 static void
-task_command_1 (char *taskno_str, int from_tty, struct inferior *inf)
+task_command_1 (const char *taskno_str, int from_tty, struct inferior *inf)
 {
   const int taskno = value_as_long (parse_and_eval (taskno_str));
   struct ada_task_info *task_info;
@@ -1314,7 +1314,7 @@ task_command_1 (char *taskno_str, int from_tty, struct inferior *inf)
    Otherwise, switch to the task indicated by TASKNO_STR.  */
 
 static void
-task_command (char *taskno_str, int from_tty)
+task_command (const char *taskno_str, int from_tty)
 {
   struct ui_out *uiout = current_uiout;