diff --git a/tests/ui/foreign/foreign-fn-linkname.rs b/tests/ui/foreign/foreign-fn-linkname.rs
index f6d820594f9..d1d6e703e3d 100644
--- a/tests/ui/foreign/foreign-fn-linkname.rs
+++ b/tests/ui/foreign/foreign-fn-linkname.rs
@@ -2,6 +2,9 @@
 // ignore-wasm32-bare no libc to test ffi with
 // ignore-sgx no libc
 
+// Ensure no false positive on "unused extern crate" lint
+#![deny(unused_extern_crates)]
+
 #![feature(rustc_private)]
 
 extern crate libc;