diff --git a/src/mesa/drivers/dri/i965/test_vec4_register_coalesce.cpp b/src/mesa/drivers/dri/i965/test_vec4_register_coalesce.cpp
index c5a3cfc56bb..83d931cb9d2 100644
--- a/src/mesa/drivers/dri/i965/test_vec4_register_coalesce.cpp
+++ b/src/mesa/drivers/dri/i965/test_vec4_register_coalesce.cpp
@@ -88,6 +88,7 @@ protected:
    virtual vec4_instruction *emit_urb_write_opcode(bool complete)
    {
       assert(!"Not reached");
+      unreachable();
    }
 };