From 394ccf76adb016b48908cd9a0fa08a1663a7ddba Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Thu, 20 Apr 2017 06:41:29 -0700
Subject: [PATCH] Make Boost use std::atomic internally

---
 configure.ac | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/configure.ac b/configure.ac
index 1e1ed49f9..496a6bcf9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -676,6 +676,10 @@ AX_BOOST_PROGRAM_OPTIONS
 AX_BOOST_THREAD
 AX_BOOST_CHRONO
 
+dnl Boost 1.56 through 1.62 allow using std::atomic instead of its own atomic
+dnl counter implementations. In 1.63 and later the std::atomic approach is default.
+m4_pattern_allow(DBOOST_AC_USE_STD_ATOMIC) dnl otherwise it's treated like a macro
+BOOST_CPPFLAGS="-DBOOST_SP_USE_STD_ATOMIC -DBOOST_AC_USE_STD_ATOMIC $BOOST_CPPFLAGS"
 
 if test x$use_reduce_exports = xyes; then
   AC_MSG_CHECKING([for working boost reduced exports])