Add a cross-compiling for Win64 example.

diff --git a/examples/cross-compiling-64-bit-windows-binary.mdwn b/examples/cross-compiling-64-bit-windows-binary.mdwn
new file mode 100644 (file)
index 0000000..3e166f3
--- /dev/null
+++ b/examples/cross-compiling-64-bit-windows-binary.mdwn
@@ -0,0 +1,125 @@
+[[!meta title="cross-compiling tinc for 64-bit Windows under Linux using MinGW"]]
+
+## Howto: cross-compiling tinc for Windows under Linux using MinGW
+
+This howto describes how to create a 64-bit Windows binary of tinc. Although it is
+possible to compile tinc under Windows itself, cross-compiling it under Linux
+is much faster. It is also much easier to get all the dependencies in a modern
+distribution. Therefore, this howto deals with cross-compiling tinc with MinGW
+under Linux on a Debian distribution.
+
+### Overview
+
+The idea is simple:
+
+* Install 64-bit MinGW.
+* Create a directory where we will perform all cross-compilations.
+* Get all the necessary sources.
+* Cross-compile everything.
+
+### Installing the prerequisites for cross-compilation
+
+There are only a few packages that need to be installed as root to get started:
+
+>     sudo apt-get install gcc-mingw32 mingw64 git-core wget
+>     sudo apt-get build-dep tinc
+
+Other Linux distributions may also have 64-bit MinGW packages, use their respective
+package management tools to install them.  Debian installs the cross-compiler
+in `/usr/amd64-mingw32msvc/`. Other distributions might install it in another
+directory however. Check in which directory
+it is installed, and replace all occurences of `amd64-mingw32msvc` in this
+example with the correct name from your distribution.
+
+At the time of writing, the gcc-mingw32 package contains the 64-bit compiler as
+well, in the future this might be put into its own package. Also, a header file
+is missing in the amd64-mingw32msvc include directory, a workaround is to
+create a symlink to the otherwise identical 32-bit version of that header file:
+
+>    ln -s ../../i586-mingw32msvc/include/getopt.h /usr/amd64-mingw32msvc/include/getopt.h
+
+### Setting up the build directory and getting the sources
+
+We will create a directory called `mingw64/` in the home directory.  We use
+apt-get and wget to get the required libraries necessary for tinc, and use
+`git` to get the latest development version of tinc.
+
+>     mkdir $HOME/mingw64
+>     cd $HOME/mingw64
+>     apt-get source liblzo2-dev zlib1g-dev
+>     wget http://www.openssl.org/source/openssl-1.0.0.tar.gz
+>     tar xzf openssl-1.0.0.tar.gz
+>     git clone git://tinc-vpn.org/tinc
+
+### Making cross-compilation easy
+
+To make cross-compiling easy, we create a script called `mingw64` that will set
+up the necessary environment variables so configure scripts and Makefiles will
+use the 64-bit MinGW version of GCC and binutils:
+
+>     mkdir $HOME/bin
+>     cat >$HOME/bin/mingw64 << EOF
+>     #!/bin/sh
+>     export CC=amd64-mingw32msvc-gcc
+>     export CXX=amd64-mingw32msvc-g++
+>     export CPP=amd64-mingw32msvc-cpp
+>     export RANLIB=amd64-mingw32msvc-ranlib
+>     export PATH="/usr/amd64-mingw32msvc/bin:$PATH"
+>     exec "$@"
+>     EOF
+
+If `$HOME/bin` is not already part of your `$PATH`, you need to add it:
+
+>     export PATH="$HOME/bin:$PATH"
+
+We use this script to call `./configure` and `make` with the right environment
+variables, but only when the `./configure` script doesn't support cross-compilation itself.
+You can also run the export commands from the `mingw64` script by
+hand instead of calling the mingw64 script for every `./configure` or `make`
+command, or execute `$HOME/bin/mingw64 $SHELL` to get a shell with these
+environment variables set, but in this howto we will call it explicitly every
+time it is needed.
+
+### Compiling LZO
+
+Cross-compiling LZO is easy:
+
+>     cd $HOME/mingw64/lzo2-2.03
+>     ./configure --host=amd64-mingw32msvc
+>     make
+>     DESTDIR=$HOME/mingw64 make install
+
+If it fails with a message about not passing the "ACC" test,
+create a symlink for the missing getopt.h file as mentioned above.
+
+### Compiling Zlib
+
+Cross-compiling Zlib is also easy, but a plain `make` failed to compile the
+tests, so we only build the static library here:
+
+>     cd $HOME/mingw64/zlib-1.2.3.3.dfsg
+>     mingw64 ./configure
+>     mingw64 make libz.a
+>     DESTDIR=$HOME/mingw64 mingw64 make install
+
+### Compiling OpenSSL
+
+Although older versions will not compile, OpenSSL 1.0.0 is easy.
+Do not use the `-j` option when compiling OpenSSL, it will break.
+
+>     cd $HOME/mingw64/openssl-1.0.0
+>     mingw64 ./Configure --openssldir=$HOME/mingw64/usr/local mingw64
+>     mingw64 make
+>     mingw64 make install
+
+### Compiling tinc
+
+Now that all the dependencies have been cross-compiled, we can cross-compile
+tinc.  Since we use a clone of the git repository here, we need to run
+`autoreconf` first. If you want to cross-compile tinc from a released tarball,
+this is not necessary.
+
+>     cd $HOME/mingw64/tinc
+>     autoreconf -fsi
+>     ./configure --host=amd64-mingw32msvc --with-openssl=$HOME/mingw64/usr/local
+>     make

diff --git a/examples/cross-compiling-windows-binary.mdwn b/examples/cross-compiling-windows-binary.mdwn
index 3a2eb56..27ea13b 100644 (file)
--- a/examples/cross-compiling-windows-binary.mdwn
+++ b/examples/cross-compiling-windows-binary.mdwn
@@ -8,6 +8,9 @@ is much faster. It is also much easier to get all the dependencies in a modern
 distribution. Therefore, this howto deals with cross-compiling tinc with MinGW
 under Linux on a Debian distribution.
 
+The result is a 32-bit executable. If you want to create a 64-bit executable,
+have a look at the [[64-bit cross-compilation example|examples/cross-compiling-64-bit-windows-binary]].
+
 ### Overview
 
 The idea is simple: