diff --git a/tool/sync_default_gems.rb b/tool/sync_default_gems.rb
index 329f0c1bd0..a353d55580 100644
--- a/tool/sync_default_gems.rb
+++ b/tool/sync_default_gems.rb
@@ -271,6 +271,7 @@ def sync_default_gems(gem)
     cp_r("#{upstream}/ext/readline", "ext")
     cp_r("#{upstream}/test/readline", "test")
     cp_r("#{upstream}/readline-ext.gemspec", "ext/readline")
+    `git checkout ext/readline/depend`
   when "did_you_mean"
     rm_rf(%w[lib/did_you_mean* test/did_you_mean])
     cp_r(Dir.glob("#{upstream}/lib/did_you_mean*"), "lib")