Major upgrade to Boost.Config symbol visibility macros for shared libraries, based on patches from Jürgen Hunold with mods by Beman Dawes. Upgrade Boost.System to use the new visibility macros. Fixes #3697 and provides foundation for fixing 2114, 2309, etc.

[SVN r62140]

test/dynamic_link_test.cpp

@@ -0,0 +1,55 @@
+//  dynamic_link_test.cpp  -------------------------------------------------------------//
+
+//  Copyright Beman Dawes 2010
+
+//  Distributed under the Boost Software License, Version 1.0.
+//  See www.boost.org/LICENSE_1_0.txt
+
+//  Library home page is www.boost.org/libs/system
+
+//--------------------------------------------------------------------------------------// 
+
+//  Dynamic link libraries (DLL's), also know as dynamic shared objects (DSO's),
+//  can cause symbol visability problems unless carefully configured. One of the
+//  manifestations, particularly with GCC, is that a system_error exception thrown from
+//  a DLL or DSO is not caught.
+//
+//  The purpose of this program is to test for that error.
+
+//--------------------------------------------------------------------------------------// 
+
+#include <boost/system/system_error.hpp>
+
+#include <iostream>
+
+namespace boost
+{
+  namespace system
+  {
+    BOOST_SYSTEM_DECL void throw_test();
+  }
+}
+
+int main()
+{
+  try
+  {
+    boost::system::throw_test();
+  }
+  catch (const boost::system::system_error& ex)
+  {
+    std::cout << "  caught boost::system::system_error as expected\n";
+    std::cout << "  what() reports " << ex.what() << '\n';
+    return 0;
+  }
+
+  catch (const std::runtime_error& ex)
+  {
+    std::cout << "  error: caught std::runtime_error instead of boost::system::system_error\n";
+    std::cout << "  what() reports " << ex.what() << '\n';
+    return 1;
+  }
+
+  std::cout << "  error: failed to catch boost::system::system_error\n";
+  return 1;
+}