Add unstable-options flag to stage!=0

diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index 7429492f914a3757cef98239bd49a99dc8b53707..86ce5fd01a812421323089946b223372b9b2cf30 100644 (file)
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -316,6 +316,11 @@ fn main() {
         }
     }
 
+    // This is required for internal lints.
+    if stage != "0" {
+        cmd.arg("-Zunstable-options");
+    }
+
     // Force all crates compiled by this compiler to (a) be unstable and (b)
     // allow the `rustc_private` feature to link to other unstable crates
     // also in the sysroot. We also do this for host crates, since those