cross-compiling tinc for 64-bit 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.
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 mingw-w64 git-core wget quilt 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/x86_64-w64-mingw32/. Other distributions might install it in another directory however. Check in which directory it is installed, and replace all occurences of
x86_64-w64-mingw32 in this example with the correct name from your distribution.
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 libssl-dev 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 PREFIX=x86_64-w64-mingw32 export CC=$PREFIX-gcc export CXX=$PREFIX-g++ export CPP=$PREFIX-cpp export RANLIB=$PREFIX-ranlib export PATH="/usr/x86_64-w64-mingw32/bin:$PATH" exec "$@" EOF chmod u+x $HOME/bin/mingw64
$HOME/bin is not already part of your
$PATH, you need to add it:
We use this script to call
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
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.
Cross-compiling LZO is easy:
cd $HOME/mingw64/lzo2-2.08 ./configure --host=x86_64-w64-mingw32 make DESTDIR=$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.
Cross-compiling Zlib is also easy, but a plain
make failed to compile the tests, so we only build the static library here:
cd $HOME/mingw64/zlib-1.2.8.dfsg mingw64 ./configure --static mingw64 make DESTDIR=$HOME/mingw64 mingw64 make install
Tinc can use either OpenSSL or LibreSSL. The latter is recommended.
cd $HOME/mingw/libressl-2.3.3 CC=x86_64-w64-mingw32-gcc ./configure --host=x86_64-w64-mingw32 make DESTDIR=$HOME/mingw make install
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 $HOME/mingw64/tinc autoreconf -fsi ./configure --host=x86_64-w64-mingw32 --with-zlib=$HOME/mingw64/usr/local make