diff --git a/block.c b/block.c
index 468cf5e67d..69a2905178 100644
--- a/block.c
+++ b/block.c
@@ -1655,8 +1655,8 @@ bdrv_open_driver(BlockDriverState *bs, BlockDriver *drv, const char *node_name,
     bs->drv = drv;
     bs->opaque = g_malloc0(drv->instance_size);
 
+    assert(!drv->bdrv_needs_filename || bs->filename[0]);
     if (drv->bdrv_file_open) {
-        assert(!drv->bdrv_needs_filename || bs->filename[0]);
         ret = drv->bdrv_file_open(bs, options, open_flags, &local_err);
     } else if (drv->bdrv_open) {
         ret = drv->bdrv_open(bs, options, open_flags, &local_err);