The instrumented libraries are a collection of Chromium's dependencies built with *SAN enabled. The MSAN libraries are required for an MSAN build to run. The others are optional, and are currently unused.
Building the libraries requires apt-get source, so the build must be done from an Ubuntu 20.04 environment. The preferred way is using a chroot. To get started, install debootstrap and schroot. If you're running a Debian-based distro, run:
sudo apt install debootstrap schroot
Create a configuration for a Focal chroot:
sudo $EDITOR /etc/schroot/chroot.d/focal_amd64.conf
Add the following to the new file, replacing the instances of thomasanderson with your own username.
[focal_amd64] description=Ubuntu 20.04 Focal for amd64 directory=/srv/chroot/focal_amd64 personality=linux root-users=thomasanderson type=directory users=thomasanderson
Bootstrap the chroot:
sudo mkdir -p /srv/chroot/focal_amd64 sudo debootstrap --variant=buildd --arch=amd64 focal /srv/chroot/focal_amd64 http://archive.ubuntu.com/ubuntu/
If your $HOME directory is not /home (as is the case on gLinux), then route /home to the real thing. schroot automatically mounts /home, which is where I'm assuming you keep your source tree and depot_tools.
sudo mount --bind "$HOME" /home
Add sources.list:
sudo $EDITOR /srv/chroot/focal_amd64/etc/apt/sources.list
Add the following contents to the file:
deb http://archive.ubuntu.com/ubuntu/ focal main restricted universe deb-src http://archive.ubuntu.com/ubuntu/ focal main restricted universe deb http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe deb-src http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe deb http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe deb-src http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe
Enter the chroot and install the necessary packages:
schroot -c focal_amd64 -u root --directory /home/dev/chromium/src apt update apt install lsb-release sudo python pkg-config libgtk2.0-bin libdrm-dev nih-dbus-tool help2man
Install library packages:
third_party/instrumented_libraries/scripts/install-build-deps.sh
Change to a non-root user:
exit schroot -c focal_amd64 -u `whoami` --directory /home/dev/chromium/src
Add depot_tools to your PATH. For example, I have it in ~/dev/depot_tools, so I use:
export PATH=/home/dev/depot_tools/:$PATH
Now we're ready to build the libraries. A clean build takes a little over 8 minutes on a 72-thread machine.
third_party/instrumented_libraries/scripts/build_and_package.py --parallel -j $(nproc) all focal
This requires write permission on the chromium-instrumented-libraries GCS bucket. dpranke@ can grant access.
# Exit the chroot. exit # Move files into place. mv *.tgz third_party/instrumented_libraries/binaries # Upload. upload_to_google_storage.py -b chromium-instrumented-libraries third_party/instrumented_libraries/binaries/msan*.tgz
After uploading, run gclient sync and test out a build with is_msan = true in your args.gn. Try running eg. chrome and unit_tests to make sure it's working. The binaries should work natively on gLinux.
When uploading a CL, make sure to add the following in the description so that the MSAN bot will run on the CQ:
CQ_INCLUDE_TRYBOTS=luci.chromium.try:linux_chromium_msan_rel_ng