diff --git a/build.rs b/build.rs
index 1933775aa407a..301f8ba23db5c 100644
--- a/build.rs
+++ b/build.rs
@@ -22,7 +22,7 @@ const ALLOWED_CFGS: &'static [&'static str] = &[
 
 // Extra values to allow for check-cfg.
 const CHECK_CFG_EXTRA: &'static [(&'static str, &'static [&'static str])] = &[
-    ("target_os", &["switch", "aix", "ohos", "hurd"]),
+    ("target_os", &["switch", "aix", "ohos", "hurd", "xros"]),
     ("target_env", &["illumos", "wasi", "aix", "ohos"]),
     (
         "target_arch",