From 0790c01f44ccdb8c376ddcf187cb54cb3e62644e Mon Sep 17 00:00:00 2001
From: Thomas Spriggs <thomas.spriggs@diffblue.com>
Date: Mon, 4 Feb 2019 11:23:45 +0000
Subject: [PATCH] Avoid narrowing conversion in `optional`

This issue was causing compile warnings on Ubuntu 18, when compiling
with conversion warnings enabled. The result of `size_of` was being
converted to `unsigned` which is a narrowing conversion on 64 bit
platforms. This commit fixes this issue by changing the type to
`std::size_t`, which is large enough to store the resultof `size_of`
without a narrowing conversion.
---
 src/nonstd/optional.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/nonstd/optional.hpp b/src/nonstd/optional.hpp
index 2634200523..816af18523 100644
--- a/src/nonstd/optional.hpp
+++ b/src/nonstd/optional.hpp
@@ -356,7 +356,7 @@ struct alignment_of_hack
     alignment_of_hack();
 };
 
-template <unsigned A, unsigned S>
+template <std::size_t A, std::size_t S>
 struct alignment_logic
 {
     enum { value = A < S ? A : S };