Looking for the right QEMU env for compiling the project

[eliabruni]

Since the compilation of all libraries is quite heavy, let's try to find the right QEMU setting to compile them all on an x86_64 machine. These are my cross compilation instructions that so far managed to compile libwebrtc.a. However, I encountered issues when trying to compile microsoft-signalr.so at the casablanca step (see also here).

Let me first give the specs of the system I used

# Operating System and Version:
lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 20.04.5 LTS
Release:    20.04
Codename:   focal

# kernel
uname -r
5.15.0-88-generic

# architecture
uname -m
x86_64

1. ARM64 Root Filesystem Setup:

   # Install the ARM64 cross-compilation toolchain and other necessary packages
   sudo apt-get update
   sudo apt-get install gcc-aarch64-linux-gnu g++-aarch64-linux-gnu binutils-aarch64-linux-gnu qemu-user-static debootstrap
   sudo debootstrap --arch arm64 --foreign bullseye rootfs
   sudo cp /usr/bin/qemu-aarch64-static rootfs/usr/bin/

2. Chroot Environment Setup:

   sudo mount -o bind /dev rootfs/dev
   sudo mount -t devpts -o gid=5,mode=620 devpts rootfs/dev/pts
   sudo chroot rootfs /bin/bash
   mount -t proc /proc /proc

3. Debootstrap Initialization:

   /debootstrap/debootstrap --second-stage

4. Basic Package Installation:

   apt-get update
   apt-get install -y git lsb-release sudo curl

5. User Environment Setup:

   useradd -m pi
   echo "pi ALL=(ALL) NOPASSWD:ALL" | tee -a /etc/sudoers
   su - pi
   bash

6. Additional Dependencies Installation:

   sudo apt-get update
   sudo apt-get install -y g++ libasound2-dev libpulse-dev libudev-dev libexpat1-dev libnss3-dev libgtk-3-dev python pulseaudio libpulse-dev build-essential libncurses5 libx11-dev
   sudo apt remove -y libssl-dev
   pulseaudio --start

7. Depot Tools Setup:

   cd /home/pi
   git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
   echo "export PATH=$(pwd)/depot_tools:\$PATH" >> ~/.bashrc
   source ~/.bashrc

8. Sysroot Dependencies for ARM64:

   sudo apt-get install -y gcc-aarch64-linux-gnu g++-aarch64-linux-gnu binutils-aarch64-linux-gnu

9. WebRTC Source Fetching:

   mkdir -p ~/webrtc && cd ~/webrtc
   fetch --nohooks webrtc
   src/build/linux/sysroot_scripts/install-sysroot.py --arch=arm64
   gclient sync -D
   cd src
   git checkout -b local-5790 branch-heads/5790
   git gc --aggressive
   gclient sync -D --force --reset --with_branch_heads --no-history

10. Clang Setup:

    cd /home/pi
    curl -OL https://github.com/llvm/llvm-project/releases/download/llvmorg-16.0.6/clang+llvm-16.0.6-aarch64-linux-gnu.tar.xz
    tar Jxvf clang+llvm-16.0.6-aarch64-linux-gnu.tar.xz
    echo 'export PATH=/home/pi/clang+llvm-16.0.6-aarch64-linux-gnu/bin:$PATH' >> ~/.bashrc
    source ~/.bashrc

11. Ninja Building and Installation:

    git clone https://github.com/martine/ninja.git
    cd ninja
    ./configure.py --bootstrap
    mv /home/pi/depot_tools/ninja /home/pi/depot_tools/ninja_org
    cp /home/pi/ninja/ninja /home/pi/depot_tools/ninja

12. GN Building and Installation:

    cd /home/pi
    git clone https://gn.googlesource.com/gn
    cd gn
    sed -i -e "s/-Wl,--icf=all//" build/gen.py
    python build/gen.py
    ninja -C out
    sudo mv /home/pi/webrtc/src/buildtools/linux64/gn /home/pi/webrtc/src/buildtools/linux64/gn_org
    cp /home/pi/gn/out/gn /home/pi/webrtc/src/buildtools/linux64/gn
    sudo mv /home/pi/depot_tools/gn /home/pi/depot_tools/gn_org
    cp /home/pi/gn/out/gn /home/pi/depot_tools/gn

13. Extra Dependencies for GN:

    sudo apt-get update
    sudo apt-get install python3-pip -y
    pip3 install setuptools

14. WebRTC Build Configuration:

    gn gen out/Release64 --args='target_os="linux" target_cpu="arm64" rtc_include_tests=false rtc_use_h264=false use_rtti=true is_component_build=false is_debug=false rtc_build_examples=false use_custom_libcxx=false rtc_build_tools=false rtc_use_pipewire=false clang_base_path="/home/pi/clang+llvm-16.0.6-aarch64-linux-gnu" clang_use_chrome_plugins=false'
    ninja -C out/Release64

15. Header Files Synchronization:

    sudo apt-get install rsync
    rsync -amv --include=*/ --include=*.h --include=*.hpp --exclude=* ./ ./include

16. Compiled libwebrtc.a Location:

    /home/pi/webrtc/src/out/Release64/obj/libwebrtc.a

[TzuHuanTai]

I tested and updated the steps for all compilations.

[eliabruni]

Awesome!