Make test/random use an intermediate library that links to Boost::random privately

test/random/CMakeLists.txt

@@ -1,4 +1,4 @@
-# Copyright 2018, 2019 Peter Dimov
+# Copyright 2018-2020 Peter Dimov
 # Distributed under the Boost Software License, Version 1.0.
 # (See accompanying file LICENSE_1_0.txt or copy at http://boost.org/LICENSE_1_0.txt)
 
@@ -28,8 +28,11 @@ else()
 
 endif()
 
-add_executable(main quick.cpp)
-target_link_libraries(main Boost::random)
+add_library(lib lib.cpp)
+target_link_libraries(lib PRIVATE Boost::random)
+
+add_executable(main main.cpp)
+target_link_libraries(main PRIVATE lib Boost::headers)
 
 enable_testing()
 add_custom_target(check COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure -C $<CONFIG>)

test/random/lib.cpp

@@ -0,0 +1,18 @@
+
+// Copyright 2017-2020 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
+
+#include <boost/random/random_device.hpp>
+
+#if defined(_MSC_VER)
+__declspec(dllexport)
+#endif
+unsigned get_random_number()
+{
+    boost::random::random_device dev;
+    return dev();
+}

test/random/main.cpp

@@ -1,19 +1,17 @@
 
-// Copyright 2017, 2018 Peter Dimov.
+// Copyright 2017-2020 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
 
-#include <boost/random/random_device.hpp>
 #include <boost/core/lightweight_test.hpp>
 
+unsigned get_random_number();
+
 int main()
 {
-    boost::random::random_device dev;
-
-    BOOST_TEST_NE( dev(), dev() );
-
+    BOOST_TEST_NE( get_random_number(), get_random_number() );
     return boost::report_errors();
 }