From 561d5acb9e6a968be8532a50611e9aa41e25a001 Mon Sep 17 00:00:00 2001
From: Eric Huss <eric@huss.org>
Date: Tue, 7 Jul 2020 06:37:47 -0700
Subject: [PATCH] Fix occasional bootstrap panic in docs.

---
 src/bootstrap/doc.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/bootstrap/doc.rs b/src/bootstrap/doc.rs
index ed351354c441d..4bec6c7791a21 100644
--- a/src/bootstrap/doc.rs
+++ b/src/bootstrap/doc.rs
@@ -156,7 +156,7 @@ impl Step for RustbookSrc {
         let index = out.join("index.html");
         let rustbook = builder.tool_exe(Tool::Rustbook);
         let mut rustbook_cmd = builder.tool_cmd(Tool::Rustbook);
-        if up_to_date(&src, &index) && up_to_date(&rustbook, &index) {
+        if builder.config.dry_run || up_to_date(&src, &index) && up_to_date(&rustbook, &index) {
             return;
         }
         builder.info(&format!("Rustbook ({}) - {}", target, name));