Updated messages about what versions of visual studio have good enough C++11 support.

dlib/cmake_utils/add_python_module

@@ -93,7 +93,7 @@ endif()
 # include dlib so we can link against it
 add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/.. dlib_build)
 if (USING_OLD_VISUAL_STUDIO_COMPILER)
-   message(FATAL_ERROR "You have to use a version of Visual Studio that supports C++11.  As of November 2017, the only version that has good enough C++11 support to compile the dlib Pyhton API is Visual Studio 2015.  Visual Studio 2017 has WORSE C++11 support than Visual Studio 2015, so Visual Studio 2017 is unable to compile the Pyhton API.  ***USE VISUAL STUDIO 2015 INSTEAD***")
+   message(FATAL_ERROR "You have to use a version of Visual Studio that supports C++11.  As of December 2017, the only versions that have good enough C++11 support to compile the dlib Pyhton API is a fully updated Visual Studio 2015 or a fully updated Visual Studio 2017.  Older versions of either of these compilers have bad C++11 support and will fail to compile the Python extension. ***SO UPDATE YOUR VISUAL STUDIO TO MAKE THIS ERROR GO AWAY***")
 endif()
 
 

dlib/cmake_utils/set_compiler_specific_options.cmake

@@ -16,11 +16,9 @@ elseif(MSVC AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.0.24210.0 )
    set(USING_OLD_VISUAL_STUDIO_COMPILER 1)
 elseif(MSVC AND (MSVC_VERSION EQUAL 1911 OR MSVC_VERSION EQUAL 1910))
    message(STATUS "******************************************************************************************")
-   message(STATUS "Visual Studio 2017 has incomplete C++11 support and is unable to compile the DNN examples.")
-   message(STATUS "So we are disabling the deep learning tools.  If you want to use the DNN tools in ")
-   message(STATUS "dlib then use Visual Studio 2015 which, surprisingly, has better C++11 support.")
-   message(STATUS "Or if you are reading this in the future and a newer version of Visual Studio that ")
-   message(STATUS "supports C++11 is available then use that.")
+   message(STATUS "Your version of Visual Studio has incomplete C++11 support and is unable to compile the ")
+   message(STATUS "DNN examples. So we are disabling the deep learning tools.  If you want to use the DNN ")
+   message(STATUS "tools in dlib then update your copy of Visual Studio.")
    message(STATUS "******************************************************************************************")
    set(USING_OLD_VISUAL_STUDIO_COMPILER 1)
 endif()