diff --git a/src/test/run-pass/cci_impl_exe.rs b/src/test/run-pass/cci_impl_exe.rs
index a34e185adcc..fd212271a46 100644
--- a/src/test/run-pass/cci_impl_exe.rs
+++ b/src/test/run-pass/cci_impl_exe.rs
@@ -1,3 +1,4 @@
+// xfail-fast - check-fast doesn't understand aux-build
 // aux-build:cci_impl_lib.rs
 
 use std;