diff --git a/src/mesa/drivers/dri/i965/brw_cfg.cpp b/src/mesa/drivers/dri/i965/brw_cfg.cpp
index 6bf99f17f58..9d6eeb37523 100644
--- a/src/mesa/drivers/dri/i965/brw_cfg.cpp
+++ b/src/mesa/drivers/dri/i965/brw_cfg.cpp
@@ -257,6 +257,8 @@ cfg_t::cfg_t(exec_list *instructions)
       }
    }
 
+   assert(cur->end);
+
    cur->end_ip = ip;
 
    make_block_array();