From e8e7715bebdd401ebacfabb66928d0f7e4733120 Mon Sep 17 00:00:00 2001
From: Manish Goregaokar <manishsmail@gmail.com>
Date: Fri, 13 Oct 2017 13:19:15 -0400
Subject: [PATCH] std: Set probe length tag on cloned hashmaps

This isn't strictly necessary for hashmap cloning to work. The tag is
used to hint for an upcoming resize, so it's good to copy this
information over.

(We can do cleverer things like actually resizing the hashmap when we
see the tag, or even cleaning up the entry order, but this requires
more thought and might not be worth it)
---
 src/libstd/collections/hash/table.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/libstd/collections/hash/table.rs b/src/libstd/collections/hash/table.rs
index 527c4ef4592c..7e623a0af17c 100644
--- a/src/libstd/collections/hash/table.rs
+++ b/src/libstd/collections/hash/table.rs
@@ -1156,6 +1156,7 @@ impl<K: Clone, V: Clone> Clone for RawTable<K, V> {
             }
 
             new_ht.size = self.size();
+            new_ht.set_tag(self.tag());
 
             new_ht
         }