Allow overriding ar command in ci_build.py #4806
Description
Problem
Botan can not be cross compiled for Windows (x86-64) from Linux (x86-64) using MXE. This is because the ar command is hardcoded for that target.
Solution
Allow users to specify the ar command.
Implementation
I've implemented this using the AR variable, which is the same way Gnu Make handles this.
Steps to reproduce
Tested on Debian 12 (bookworm).
- Build MXE & update your PATH (see below)
- Get the dependencies (see further below)
AR=x86_64-w64-mingw32.static-ar CXX=x86_64-w64-mingw32.static-g++ python3 ./src/scripts/ci_build.py --os=windows --cc=gcc cross-win64
Fails before the associated patch, succeeds after the patch.
Building MXE
Takes about an hour on my computer.
sudo apt-get install -y autoconf automake autopoint bash bison bzip2 flex g++ g++-multilib gettext git gperf intltool libc6-dev-i386 libgdk-pixbuf2.0-dev libltdl-dev libgl-dev libpcre3-dev libssl-dev libtool-bin libxml-parser-perl lzip make openssl p7zip-full patch perl python3 python3-distutils python3-mako python3-packaging python3-pkg-resources python3-setuptools python-is-python3 ruby sed sqlite3 unzip wget xz-utils
git clone https://github.com/mxe/mxe.git
cd mxe
make MXE_TARGETS='x86_64-w64-mingw32.static i686-w64-mingw32.static' cc
export PATH="`pwd`/usr/bin:$PATH"
cd ..Note 1: The list of apt-packages is not minimized, so there might be some packages in there that are not strictly required.
Note 2: There is an MXE apt repo, but it has an old version of gcc, which is why we have to build it from source. I plan on trying to coordinate with the MXE maintainers to see if I can get a new version built and put up there.
Install dependencies
arch="x86-64"
sudo apt-get update
sudo apt-get install -y software-properties-common lsb-release gnupg
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 86B72ED9
sudo add-apt-repository -y "deb [arch=amd64] https://pkg.mxe.cc/repos/apt buster main"
sudo apt-get update
sudo apt install -y mingw-w64-common mxe-$arch-w64-mingw32.static-qtwebsockets mxe-$arch-w64-mingw32.static-libwebsockets mxe-$arch-w64-mingw32.static-libgcrypt mxe-$arch-w64-mingw32.static-qtbase mxe-$arch-w64-mingw32.static-qt mxe-$arch-w64-mingw32.static-libusb1 libargon2-dev libbotan-2-dev libykpers-1-dev libpcsclite-dev cmake libqt5svg5-dev qttools5-dev libminizip-dev libkeyutils-dev libqt5x11extras5-dev libxtst-dev libqrencode-dev asciidoctor wineNote: The list of apt-packages is not minimized, so there might be some packages in there that are not strictly required.