From 2c4687431f978f02a3780e24b8b701d22aa32d9c Mon Sep 17 00:00:00 2001
From: Malte Skarupke <malteskarupke@web.de>
Date: Sun, 15 Jul 2018 19:46:47 -0400
Subject: [PATCH] Fix that Fibonacci hashing doesn't work with a size of 1. It
 now just rounds up to size 2.

---
 flat_hash_map.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/flat_hash_map.hpp b/flat_hash_map.hpp
index 33fc221..a8723ee 100644
--- a/flat_hash_map.hpp
+++ b/flat_hash_map.hpp
@@ -1278,7 +1278,7 @@ struct fibonacci_hash_policy
 
     int8_t next_size_over(size_t & size) const
     {
-        size = detailv3::next_power_of_two(size);
+        size = std::max(size_t(2), detailv3::next_power_of_two(size));
         return 64 - detailv3::log2(size);
     }
     void commit(int8_t shift)