Sun, 20 Apr 2008

Cross Compiling for Legacy Win32 Systems (Part 2).

Cross compiling from Linux to Windows requires the installation of a couple of packages. On a Debian or Ubuntu system this can be done using: 


  sudo apt-get install build-essential
  sudo apt-get install mingw32 mingw32-binutils mingw32-runtime wine

I'm running Ubuntu's Hardy Heron pre-release and the following is known to work with these versions: 


  mingw32               4.2.1.dfsg-1ubuntu1
  mingw32-binutils      2.17.50-20070129.1-1
  mingw32-runtime       3.13-1
  wine                  0.9.59-0ubuntu5

For an example of a project which can be successfully cross-compiled, I have chosen libogg which is one of the two libraries required to encode and decode Ogg/Vorbis files. I also happen to know that the current libogg sources in the Xiph Foundation's SVN repository cross-compile from Linux to Windows correctly because I committed the patch to make it possible.

However, we need to look ahead a little. After we have cross compiled libogg we will also want to cross compile the associated libvorbis library which relies on libogg. We therefore need to configure libogg so that when we install it, it can be found by the libvorbis configure script.

For me that meant creating a MinGW32 directory in my home directory: 


  mkdir $HOME/MinGW32

The next step to to grab the libogg source code from the Xiph SVN server. This can be achieved using the command: 


  svn co http://svn.xiph.org/trunk/ogg libogg

Changing into the libogg directory, we are now ready to configure, test and install the library. That can be done using: 


  ./autogen.sh
  ./configure --host=i586-mingw32msvc --target=i586-mingw32msvc \
      --build=i586-linux --prefix=$HOME/MinGW32
  make
  make check
  make install

The first command above, runs the auto tools to generate that configure script. The second command, configure is broken across two lines. It sets up the generated Makefiles to compile Windows binaries from a Linux host, with the install directory we set up before. The third line builds the windows version of libogg, the fourth line runs the test suite, with the windows executables being run under WINE and the final line installs everything in the MinGW32 directory created earlier.

All of the above commands should pass without errors. If they don't, check your versions of of the mingw cross compiler tools and/or WINE.

Posted at: 20:51 | Category: CodeHacking/MinGWCross | Permalink