diff --git a/compiler/rustc_serialize/src/serialize.rs b/compiler/rustc_serialize/src/serialize.rs
index 2d37f5bdab800..bae5f259fccf4 100644
--- a/compiler/rustc_serialize/src/serialize.rs
+++ b/compiler/rustc_serialize/src/serialize.rs
@@ -325,7 +325,7 @@ impl<D: Decoder, const N: usize> Decodable<D> for [u8; N] {
     }
 }
 
-impl<'a, S: Encoder, T: Encodable<S>> Encodable<S> for Cow<'a, [T]>
+impl<S: Encoder, T: Encodable<S>> Encodable<S> for Cow<'_, [T]>
 where
     [T]: ToOwned<Owned = Vec<T>>,
 {
@@ -345,14 +345,14 @@ where
     }
 }
 
-impl<'a, S: Encoder> Encodable<S> for Cow<'a, str> {
+impl<S: Encoder> Encodable<S> for Cow<'_, str> {
     fn encode(&self, s: &mut S) {
         let val: &str = self;
         val.encode(s)
     }
 }
 
-impl<'a, D: Decoder> Decodable<D> for Cow<'a, str> {
+impl<D: Decoder> Decodable<D> for Cow<'_, str> {
     fn decode(d: &mut D) -> Cow<'static, str> {
         let v: String = Decodable::decode(d);
         Cow::Owned(v)
diff --git a/src/bootstrap/src/core/builder/tests.rs b/src/bootstrap/src/core/builder/tests.rs
index ab36193f8b614..402d1b3411dab 100644
--- a/src/bootstrap/src/core/builder/tests.rs
+++ b/src/bootstrap/src/core/builder/tests.rs
@@ -6,6 +6,7 @@ use super::*;
 use crate::Flags;
 use crate::core::build_steps::doc::DocumentationFormat;
 use crate::core::config::Config;
+use crate::core::download::is_download_ci_available;
 
 fn configure(cmd: &str, host: &[&str], target: &[&str]) -> Config {
     configure_with_args(&[cmd.to_owned()], host, target)
@@ -225,6 +226,10 @@ fn ci_rustc_if_unchanged_logic() {
         |&_| Ok(Default::default()),
     );
 
+    if !is_download_ci_available(&config.build.triple, config.llvm_assertions) {
+        return;
+    }
+
     if config.rust_info.is_from_tarball() {
         return;
     }
@@ -257,7 +262,9 @@ fn ci_rustc_if_unchanged_logic() {
         .unwrap()
         .success();
 
-    assert!(has_changes == config.download_rustc_commit.is_none());
+    if config.download_rustc_commit.is_some() {
+        assert!(!has_changes);
+    }
 }
 
 mod defaults {