From 42c794ad422865d66d3bdf4b20286f1f83f3cddb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Robin=20Lind=C3=A9n?= <dev@robinlinden.eu>
Date: Thu, 16 Aug 2018 23:38:02 +0200
Subject: [PATCH 1/2] Add test checking that MPL_ASSERT_MSG works under VC++8

---
 test/Jamfile.v2        |  1 +
 test/assert_vc8.hpp    | 28 ++++++++++++++++++++++++++++
 test/assert_vc8_p1.cpp | 23 +++++++++++++++++++++++
 test/assert_vc8_p2.cpp | 19 +++++++++++++++++++
 4 files changed, 71 insertions(+)
 create mode 100644 test/assert_vc8.hpp
 create mode 100644 test/assert_vc8_p1.cpp
 create mode 100644 test/assert_vc8_p2.cpp

diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index a62a3b6..f345656 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -13,6 +13,7 @@ compile apply_wrap.cpp ;
 compile arithmetic.cpp ;
 compile as_sequence.cpp ;
 compile assert.cpp ;
+link assert_vc8_p1.cpp assert_vc8_p2.cpp ;
 compile at.cpp ;
 compile back.cpp ;
 compile bind.cpp ;
diff --git a/test/assert_vc8.hpp b/test/assert_vc8.hpp
new file mode 100644
index 0000000..f54df0e
--- /dev/null
+++ b/test/assert_vc8.hpp
@@ -0,0 +1,28 @@
+
+// Copyright Robin Linden 2018
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/mpl for documentation.
+
+// $Id$
+// $Date$
+// $Revision$
+
+// Part of a test to demonstrate a linking error with
+// BOOST_MPL_ASSERT_MSG inside of functions under VC++8.
+
+#include <boost/mpl/assert.hpp>
+
+template<class T>
+bool func()
+{
+    BOOST_MPL_ASSERT_MSG(
+        true,
+        ALWAYS_TRUE,
+        (T));
+
+    return true;
+}
diff --git a/test/assert_vc8_p1.cpp b/test/assert_vc8_p1.cpp
new file mode 100644
index 0000000..2883135
--- /dev/null
+++ b/test/assert_vc8_p1.cpp
@@ -0,0 +1,23 @@
+
+// Copyright Robin Linden 2018
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/mpl for documentation.
+
+// $Id$
+// $Date$
+// $Revision$
+
+// Part of a test to demonstrate a linking error with
+// BOOST_MPL_ASSERT_MSG inside of functions under VC++8.
+
+#include "assert_vc8.hpp"
+
+static bool a = func<int>();
+
+int main()
+{
+}
diff --git a/test/assert_vc8_p2.cpp b/test/assert_vc8_p2.cpp
new file mode 100644
index 0000000..6b53573
--- /dev/null
+++ b/test/assert_vc8_p2.cpp
@@ -0,0 +1,19 @@
+
+// Copyright Robin Linden 2018
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/mpl for documentation.
+
+// $Id$
+// $Date$
+// $Revision$
+
+// Part of a test to demonstrate a linking error with
+// BOOST_MPL_ASSERT_MSG inside of functions under VC++8.
+
+#include "assert_vc8.hpp"
+
+static bool a = func<int>();

From e44b2ae761540776f09c83021c11253898029d9b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Robin=20Lind=C3=A9n?= <dev@robinlinden.eu>
Date: Mon, 13 Aug 2018 20:10:57 +0200
Subject: [PATCH 2/2] Fix BOOST_MPL_ASSERT_MSG for VC++8

The struct member function inside BOOST_MPL_ASSERT_MSG_IMPL was causing
multiple definitions of the same symbol when used inside e.g. template
functions.

An example of where this is a big issue is in the boost/geometry library
where you currently only can call each function once for each geometry
or you get hit by the multiple definitions linking error.

This fix* works around the issue by gracefully degrading to
BOOST_STATIC_ASSERT_MSG instead of failing during linking.
---
 include/boost/mpl/assert.hpp | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/include/boost/mpl/assert.hpp b/include/boost/mpl/assert.hpp
index e41b583..baf43e0 100644
--- a/include/boost/mpl/assert.hpp
+++ b/include/boost/mpl/assert.hpp
@@ -443,8 +443,16 @@ BOOST_MPL_AUX_ASSERT_CONSTANT( \
 /**/
 #endif
 
-#define BOOST_MPL_ASSERT_MSG( c, msg, types_ ) \
+// Work around BOOST_MPL_ASSERT_MSG_IMPL generating multiple definition linker errors on VC++8.
+#if defined(BOOST_MSVC) && BOOST_MSVC < 1500
+#   include <boost/static_assert.hpp>
+#   define BOOST_MPL_ASSERT_MSG( c, msg, types_ ) \
+BOOST_STATIC_ASSERT_MSG( c, #msg ) \
+/**/
+#else
+#   define BOOST_MPL_ASSERT_MSG( c, msg, types_ ) \
 BOOST_MPL_ASSERT_MSG_IMPL( BOOST_MPL_AUX_PP_COUNTER(), c, msg, types_ ) \
 /**/
+#endif
 
 #endif // BOOST_MPL_ASSERT_HPP_INCLUDED