diff --git a/src/pipewire/global.c b/src/pipewire/global.c
index cf5dcdd42..e44caf1e6 100644
--- a/src/pipewire/global.c
+++ b/src/pipewire/global.c
@@ -207,7 +207,7 @@ const struct pw_properties *pw_global_get_properties(struct pw_global *global)
 
 SPA_EXPORT
 int pw_global_update_keys(struct pw_global *global,
-		     const struct spa_dict *dict, const char *keys[])
+		     const struct spa_dict *dict, const char * const keys[])
 {
 	if (global->registered)
 		return -EINVAL;
diff --git a/src/pipewire/global.h b/src/pipewire/global.h
index e04c4f47d..1ec18fbf6 100644
--- a/src/pipewire/global.h
+++ b/src/pipewire/global.h
@@ -118,7 +118,7 @@ const struct pw_properties *pw_global_get_properties(struct pw_global *global);
 
 /** Update the global properties, must be done when unregistered */
 int pw_global_update_keys(struct pw_global *global,
-		     const struct spa_dict *dict, const char *keys[]);
+		     const struct spa_dict *dict, const char * const keys[]);
 
 /** Get the object associated with the global. This depends on the type of the
   * global */