Windows builds are much more cumbersome than Linux ones. Despite that, GCC toolchain is available on Windows. Through the MinGW project, OpenJDK uses official Microsoft compilers from Visual Studio and Windows SDK. This brings a lot of complications because the Microsoft toolchain doesn't work well with the Unix-like environment provided by Cygwin.
Visual Studio.NET 2003 is required to build i586 binaries. OpenJDK 6 on Windows i586 is the only version in this book that cannot be built using freely available tools. VS 2003 was chosen for OpenJDK 6 because it supports Windows 2000, which was critical at the time of Sun Java 6's development.
For this recipe, we should have Windows 7 SP1 i586 running with no antivirus software installed. Antivirus software is not allowed because it may interfere with the Cygwin runtime.