diff --git a/src/connection.c b/src/connection.c
index b89166fb..6cb2e574 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -524,7 +524,7 @@ wl_argument_from_va_list(const char *signature, union wl_argument *args,
 			args[i].o = va_arg(ap, struct wl_object *);
 			break;
 		case 'a':
-			args[i].a = va_arg(ap, struct wl_array *);
+			args[i].a = va_arg(ap, const struct wl_array *);
 			break;
 		case 'h':
 			args[i].h = va_arg(ap, int32_t);
diff --git a/src/scanner.c b/src/scanner.c
index c512d231..53ef810d 100644
--- a/src/scanner.c
+++ b/src/scanner.c
@@ -1120,7 +1120,7 @@ emit_type(struct arg *a)
 		printf("struct %s *", a->interface_name);
 		break;
 	case ARRAY:
-		printf("struct wl_array *");
+		printf("const struct wl_array *");
 		break;
 	}
 }
diff --git a/src/wayland-util.h b/src/wayland-util.h
index c99069cc..dfa0b0d0 100644
--- a/src/wayland-util.h
+++ b/src/wayland-util.h
@@ -681,7 +681,7 @@ union wl_argument {
 	const char *s;       /**< `string` */
 	struct wl_object *o; /**< `object` */
 	uint32_t n;          /**< `new_id` */
-	struct wl_array *a;  /**< `array`  */
+	const struct wl_array *a;  /**< `array`  */
 	int32_t h;           /**< `fd`     */
 };