Wt

Forgot to include the main.cpp code. I have been able to slim it down to the following code. If I comment out the createApplication function and rebuild the program, then it will work and execute the code in main. (the code bellow gives the unhandled exception that I wrote about in my previous post)

#include <Wt/WApplication>

Wt::WApplication *createApplication(const Wt::WEnvironment& env)
{
    /*
     * You could read information from the environment to decide whether
     * the user has permission to start a new application
     */
    return new Wt::WApplication(env);
}

int main(int argc, char **argv)
{
    int i = 5; // some basic code to put a break point on
    i++;

    return 1;
}

Hello Leif,

It looks to me that you are indeed mixing msvc runtime libraries. Since your mail is so elaborate, I could reconstruct your situation (I used boost 1.38 but that shouldn't make the difference) and made some modifications.

First of all, let me clarify the (maybe not-so-well documented) fact that since Wt 3.0.0, we adopted the following naming scheme for our libraries (both on unix and windows):

non-debug libraries: wt.lib, wthttp.lib

debug libraries: wtd.lib, wthttpd.lib (they have a 'd' suffix)

On windows, non-debug libraries are linked against the non-debug msvc C/C runtime libraries; debug libraries are linked against the debug runtimes. Never mix within a single executable DLLs/libraries linked against different versions fo the runtime...

In order to use the correct version of the library, the CMakeLists.txt should now look like this:

INCLUDE_DIRECTORIES(
    "C:/Program Files/WT/include"
    "c:/Program Files/Boost/boost_1_38"
    )
LINK_DIRECTORIES(
    "C:/Program Files/WT/lib"
    "c:/Program Files/Boost/boost_1_38/lib"
    )

ADD_EXECUTABLE(wt_cmake.wt
    main.cpp
    )

# Or, for built-in httpd deployment:
TARGET_LINK_LIBRARIES(wt_cmake.wt
 optimized wthttp debug wthttpd
 optimized wt debug wtd
)

I recommend you to:

1. Delete c:/Program Files/WT (the Wt installation directory) every time before you install a new version of Wt
   
2. Build and install both Release and Debug versions of Wt (you can select this in the drop down box next to the run button in the msvc ide)
   
3. Use the CMakeLists.txt above to build your own applications (the right Wt library will automatically be selected depending for release and debug builds)
   
4. Always watch closely for linker warnings that mention the mixing of debug/release versions of CRT libraries

Let me know if this helps!

Regards,

Wim.

Hi Wim,

Thank you for taking yourself time to reproducing my case and providing such high quality feedback on my problem. It is always a question if you are going to get help or scare people off by including much details.

I've removed the Wt installation (C:\Program( files)\Wt) and cleared the old build. Currently I'm compiling the debug + release version of wt after having re-generated the solution files. Hopefully this will solve my problems. If it is a mismatch between release and debug versions it explains why the examples worked but not my project. I'll report back later if I was able to solve the problem (and how) or not.

Off topic: Build message

One thing I saw the previous time when I compiled Wt, and also now when I re-compiled everything for both Debug and Release is this message (in the compile log for the 'wt' project):

..
..
Request.C
Client.C
Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately. For example:
- add -D_WIN32_WINNT=0x0501 to the compiler command line; or
- add _WIN32_WINNT=0x0501 to your project's Preprocessor Definitions.
Assuming _WIN32_WINNT=0x0501 (i.e. Windows XP target).
WWidgetItem.C
WWidget.C
..
..

I don't know if maybe CMake would be capable of doing this detection? It is making a correct guess for me though.

Do you want me to create a bug issue in the tracker for this?

Regards,

Leif

Hi again Wim,

The recompilation finished and my project compiles fine after changing the CMakeLists.txt file according to your suggestion.

What i did (for future reference):

• I removed the existing installation C:\Program\Wt (corresponds to C:\Program files\Wt on the English version of Windows XP)
• Cleaned the Wt 3.0.0 project using the clean command in Visual Studio
• Re-generated the solution files with CMake
• Built Debug & Release configuration of Wt
• Installed both Debug & Release configuration of Wt

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• Replaced the CMakeList.txt of my project with the one Wim provided above.
• Changed the paths to Wt and boost to affect the paths on my system
• CMake on my project
• Built my project

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• Now it works!

(I have an issue with the program arguments not getting sent to the program properly (argc == 1), but that might be related to not clearing the project files before generating the new one. That is anyway possible to work around by hard coding the arguments sent to WRun in main(..), which is still okay since they are easier to access there during the development.)

Thank you very much for your help.

Regards,

Leif

Leif,

Good to hear it works now.

As far as I understand the _WIN32_WINNT or _WIN32_WINDOWS warnings, it has to do with on what versions of windows you want to deploy your programs on. If you set this higher, the 'newer' functions of the api are also declared in the windows header files, but your executable will no longer run on the older versions of Windows. It is a typical windows thing, it has nothing special to do with Wt or boost (afaik), but boost asio does print an explicit warning about it.

See also: http://blogs.msdn.com/oldnewthing/archive/2007/04/11/2079137.aspx

Regards,

Wim.