diff --git a/include/libweston/libweston.h b/include/libweston/libweston.h
index 25fca47b1..f3f3e85c5 100644
--- a/include/libweston/libweston.h
+++ b/include/libweston/libweston.h
@@ -2066,6 +2066,7 @@ enum weston_compositor_backend {
 };
 
 enum weston_renderer_type {
+	WESTON_RENDERER_AUTO = 0,
 	WESTON_RENDERER_NOOP = 1,
 	WESTON_RENDERER_PIXMAN = 2,
 	WESTON_RENDERER_GL = 3,
diff --git a/libweston/backend-headless/headless.c b/libweston/backend-headless/headless.c
index 965c82854..e3fdcfb41 100644
--- a/libweston/backend-headless/headless.c
+++ b/libweston/backend-headless/headless.c
@@ -218,6 +218,8 @@ headless_output_disable(struct weston_output *base)
 		break;
 	case WESTON_RENDERER_NOOP:
 		break;
+	case WESTON_RENDERER_AUTO:
+		unreachable("cannot have auto renderer at runtime");
 	}
 
 	return 0;
@@ -351,6 +353,8 @@ headless_output_enable(struct weston_output *base)
 		break;
 	case WESTON_RENDERER_NOOP:
 		break;
+	case WESTON_RENDERER_AUTO:
+		unreachable("cannot have auto renderer at runtime");
 	}
 
 	if (ret < 0) {