diff --git a/src/cargo/util/flock.rs b/src/cargo/util/flock.rs
index 755bcdcd910..2986abb905d 100644
--- a/src/cargo/util/flock.rs
+++ b/src/cargo/util/flock.rs
@@ -378,7 +378,6 @@ mod sys {
             // For targets in which they are the same, the duplicate pattern causes a warning.
             #[allow(unreachable_patterns)]
             Some(libc::ENOTSUP | libc::EOPNOTSUPP) => true,
-            #[cfg(target_os = "linux")]
             Some(libc::ENOSYS) => true,
             _ => false,
         }