From 7df4b812f07c503dc10037797f80a9aaa6b84aac Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?John=20K=C3=A5re=20Alsaker?= <john.kare.alsaker@gmail.com>
Date: Thu, 6 Dec 2018 14:23:29 +0100
Subject: [PATCH] Fix bug in from_key_hashed_nocheck

---
 src/libstd/collections/hash/map.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/libstd/collections/hash/map.rs b/src/libstd/collections/hash/map.rs
index 536ce2e16a09b..11ccf206d00b3 100644
--- a/src/libstd/collections/hash/map.rs
+++ b/src/libstd/collections/hash/map.rs
@@ -11,6 +11,7 @@
 use self::Entry::*;
 use self::VacantEntryState::*;
 
+use intrinsics::unlikely;
 use collections::CollectionAllocErr;
 use cell::Cell;
 use borrow::Borrow;
@@ -1992,6 +1993,9 @@ impl<'a, K, V, S> RawEntryBuilder<'a, K, V, S>
     fn search<F>(self, hash: u64, is_match: F, compare_hashes: bool) -> Option<(&'a K, &'a V)>
         where F: FnMut(&K) -> bool
     {
+        if unsafe { unlikely(self.map.table.size() == 0) } {
+            return None;
+        }
         match search_hashed_nonempty(&self.map.table,
                                      SafeHash::new(hash),
                                      is_match,