Merge branch 'feature/pragma-message' into develop

# Fixed Conflicts:
#	doc/html/index.html

include/boost/config/detail/suffix.hpp

@@ -537,25 +537,10 @@ namespace std{ using ::type_info; }
 
 // ---------------------------------------------------------------------------//
 
-//
 // Helper macro BOOST_STRINGIZE:
-// Converts the parameter X to a string after macro replacement
-// on X has been performed.
-//
-#define BOOST_STRINGIZE(X) BOOST_DO_STRINGIZE(X)
-#define BOOST_DO_STRINGIZE(X) #X
-
-//
 // Helper macro BOOST_JOIN:
-// The following piece of macro magic joins the two
-// arguments together, even when one of the arguments is
-// itself a macro (see 16.3.1 in C++ standard).  The key
-// is that macro expansion of macro arguments does not
-// occur in BOOST_DO_JOIN2 but does in BOOST_DO_JOIN.
-//
-#define BOOST_JOIN( X, Y ) BOOST_DO_JOIN( X, Y )
-#define BOOST_DO_JOIN( X, Y ) BOOST_DO_JOIN2(X,Y)
-#define BOOST_DO_JOIN2( X, Y ) X##Y
+
+#include <boost/config/helper_macros.hpp>
 
 //
 // Set some default values for compiler/library/platform names.

include/boost/config/helper_macros.hpp

@@ -0,0 +1,37 @@
+#ifndef BOOST_CONFIG_HELPER_MACROS_HPP_INCLUDED
+#define BOOST_CONFIG_HELPER_MACROS_HPP_INCLUDED
+
+//  Copyright 2001 John Maddock.
+//  Copyright 2017 Peter Dimov.
+//
+//  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
+//
+//  BOOST_STRINGIZE(X)
+//  BOOST_JOIN(X, Y)
+//
+//  Note that this header is C compatible.
+
+//
+// Helper macro BOOST_STRINGIZE:
+// Converts the parameter X to a string after macro replacement
+// on X has been performed.
+//
+#define BOOST_STRINGIZE(X) BOOST_DO_STRINGIZE(X)
+#define BOOST_DO_STRINGIZE(X) #X
+
+//
+// Helper macro BOOST_JOIN:
+// The following piece of macro magic joins the two
+// arguments together, even when one of the arguments is
+// itself a macro (see 16.3.1 in C++ standard).  The key
+// is that macro expansion of macro arguments does not
+// occur in BOOST_DO_JOIN2 but does in BOOST_DO_JOIN.
+//
+#define BOOST_JOIN(X, Y) BOOST_DO_JOIN(X, Y)
+#define BOOST_DO_JOIN(X, Y) BOOST_DO_JOIN2(X,Y)
+#define BOOST_DO_JOIN2(X, Y) X##Y
+
+#endif // BOOST_CONFIG_HELPER_MACROS_HPP_INCLUDED

include/boost/config/pragma_message.hpp

@@ -0,0 +1,29 @@
+#ifndef BOOST_CONFIG_PRAGMA_MESSAGE_HPP_INCLUDED
+#define BOOST_CONFIG_PRAGMA_MESSAGE_HPP_INCLUDED
+
+//  Copyright 2017 Peter Dimov.
+//
+//  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
+//
+//  BOOST_PRAGMA_MESSAGE("message")
+//
+//  Expands to the equivalent of #pragma message("message")
+//
+//  Note that this header is C compatible.
+
+#include <boost/config/helper_macros.hpp>
+
+#if defined(BOOST_DISABLE_PRAGMA_MESSAGE)
+# define BOOST_PRAGMA_MESSAGE(x)
+#elif defined(__GNUC__)
+# define BOOST_PRAGMA_MESSAGE(x) _Pragma(BOOST_STRINGIZE(message(x)))
+#elif defined(_MSC_VER)
+# define BOOST_PRAGMA_MESSAGE(x) __pragma(message(__FILE__ "(" BOOST_STRINGIZE(__LINE__) "): note: " x))
+#else
+# define BOOST_PRAGMA_MESSAGE(x)
+#endif
+
+#endif // BOOST_CONFIG_PRAGMA_MESSAGE_HPP_INCLUDED