diff --git a/src/doc/rustc-dev-guide b/src/doc/rustc-dev-guide
index 66be765404efb..7adfab42bab04 160000
--- a/src/doc/rustc-dev-guide
+++ b/src/doc/rustc-dev-guide
@@ -1 +1 @@
-Subproject commit 66be765404efb82c6bc2735473cbd3472f777dc0
+Subproject commit 7adfab42bab045a848126895c2f1e09927c1331a
diff --git a/src/tools/rustbook/src/main.rs b/src/tools/rustbook/src/main.rs
index 01f324f0c5a0a..60bd0b72910a4 100644
--- a/src/tools/rustbook/src/main.rs
+++ b/src/tools/rustbook/src/main.rs
@@ -108,7 +108,9 @@ pub fn linkcheck(
                 is_real_error = true;
             }
             Reason::UnsuccessfulServerResponse(status) => {
-                if status.is_client_error() {
+                if status.as_u16() == 429 {
+                    eprintln!("Received 429 (TOO_MANY_REQUESTS) for link `{}`", link.link.uri);
+                } else if status.is_client_error() {
                     is_real_error = true;
                 } else {
                     eprintln!("Unsuccessful server response for link `{}`", link.link.uri);