From aab3dbd24ca50b11207d3391adaa121877da1927 Mon Sep 17 00:00:00 2001
From: Kurtis Rader <krader@skepticism.us>
Date: Sun, 13 Aug 2017 15:25:02 -0700
Subject: [PATCH] Revert "Removed unused <mutex> header include"

This reverts commit 87db424e45a7b04ca45d9dca735b2368a123977f.
It was meant for the major branch.
---
 src/exec.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/exec.cpp b/src/exec.cpp
index 8804c3e28..918d98fa3 100644
--- a/src/exec.cpp
+++ b/src/exec.cpp
@@ -21,6 +21,7 @@
 #include <algorithm>
 #include <map>
 #include <memory>
+#include <mutex>
 #include <string>
 #include <type_traits>
 #include <vector>