There are instructions for other platforms linked from the get the code page.
Are you a Google employee? See go/building-chrome instead.
[TOC]
- A 64-bit Intel machine with at least 8GB of RAM. More than 16GB is highly recommended.
- At least 100GB of free disk space.
- You must have Git and Python v3.6+ installed already (and
python3
must point to a Python v3.6+ binary).
Most development is done on Ubuntu (currently 18.04, Bionic Beaver). There are some instructions for other distros below, but they are mostly unsupported.
Clone the depot_tools
repository:
$ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
Add depot_tools
to the end of your PATH (you will probably want to put this
in your ~/.bashrc
or ~/.zshrc
). Assuming you cloned depot_tools
to
/path/to/depot_tools
:
$ export PATH="$PATH:/path/to/depot_tools"
When cloning depot_tools
to your home directory do not use ~
on PATH,
otherwise gclient runhooks
will fail to run. Rather, you should use either
$HOME
or the absolute path:
$ export PATH="$PATH:${HOME}/depot_tools"
Create a chromium
directory for the checkout and change to it (you can call
this whatever you like and put it wherever you like, as long as the full path
has no spaces):
$ mkdir ~/chromium && cd ~/chromium
Run the fetch
tool from depot_tools to check out the code and its
dependencies.
$ fetch --nohooks chromium
If you don't want the full repo history, you can save a lot of time by
adding the --no-history
flag to fetch
.
Expect the command to take 30 minutes on even a fast connection, and many hours on slower ones.
If you've already installed the build dependencies on the machine (from another
checkout, for example), you can omit the --nohooks
flag and fetch
will automatically execute gclient runhooks
at the end.
When fetch
completes, it will have created a hidden .gclient
file and a
directory called src
in the working directory. The remaining instructions
assume you have switched to the src
directory:
$ cd src
Once you have checked out the code, and assuming you're using Ubuntu, run build/install-build-deps.sh
$ ./build/install-build-deps.sh
You may need to adjust the build dependencies for other distros. There are some notes at the end of this document, but we make no guarantees for their accuracy.
Once you've run install-build-deps
at least once, you can now run the
Chromium-specific hooks, which will download additional binaries and other
things you might need:
$ gclient runhooks
Optional: You can also install API keys if you want your build to talk to some Google services, but this is not necessary for most development and testing purposes.
Chromium uses Ninja as its main build tool along with
a tool called GN
to generate .ninja
files. You can create any number of build directories
with different configurations. To create a build directory, run:
$ gn gen out/Default
- You only have to run this once for each new build directory, Ninja will update the build files as needed.
- You can replace
Default
with another name, but it should be a subdirectory ofout
. - For other build arguments, including release settings, see GN build configuration. The default will be a debug component build matching the current host operating system and CPU.
- For more info on GN, run
gn help
on the command line or read the quick start guide.
This section contains some things you can change to speed up your builds, sorted so that the things that make the biggest difference are first.
Google developed the distributed compiler called Goma.
If you would like to use Goma
provisioned by Google,
please follow Goma for Chromium contributors.
If you are a Google employee, see go/building-chrome instead.
By default, the build includes support for
Native Client (NaCl), but
most of the time you won't need it. You can set the GN argument
enable_nacl=false
and it won't be built.
By default GN produces a build with all of the debug assertions enabled
(is_debug=true
) and including full debug info (symbol_level=2
). Setting
symbol_level=1
will produce enough information for stack traces, but not
line-by-line debugging. Setting symbol_level=0
will include no debug
symbols at all. Either will speed up the build compared to full symbols.
Due to its extensive use of templates, the Blink code produces about half
of our debug symbols. If you don't ever need to debug Blink, you can set
the GN arg blink_symbol_level=0
. Similarly, if you don't need to debug v8 you
can improve build speeds by setting the GN arg v8_symbol_level=0
.
Icecc is the distributed compiler with a central scheduler to share build load. Currently, many external contributors use it. e.g. Intel, Opera, Samsung (this is not useful if you're using Goma).
In order to use icecc
, set the following GN args:
use_debug_fission=false
is_clang=false
See these links for more on the bundled_binutils limitation, the debug fission limitation.
Using the system linker may also be necessary when using glibc 2.21 or newer. See related bug.
You can use ccache to speed up local builds (again, this is not useful if you're using Goma).
Increase your ccache hit rate by setting CCACHE_BASEDIR
to a parent directory
that the working directories all have in common (e.g.,
/home/yourusername/development
). Consider using
CCACHE_SLOPPINESS=include_file_mtime
(since if you are using multiple working
directories, header times in svn sync'ed portions of your trees will be
different - see
the ccache troubleshooting section
for additional information). If you use symbolic links from your home directory
to get to the local physical disk directory where you keep those working
development directories, consider putting
alias cd="cd -P"
in your .bashrc
so that $PWD
or cwd
always refers to a physical, not
logical directory (and make sure CCACHE_BASEDIR
also refers to a physical
parent).
If you tune ccache correctly, a second working directory that uses a branch
tracking trunk and is up to date with trunk and was gclient sync'ed at about the
same time should build chrome in about 1/3 the time, and the cache misses as
reported by ccache -s
should barely increase.
This is especially useful if you use git-worktree and keep multiple local working directories going at once.
You can use tmpfs for the build output to reduce the amount of disk writes required. I.e. mount tmpfs to the output directory where the build output goes:
As root:
mount -t tmpfs -o size=20G,nr_inodes=40k,mode=1777 tmpfs /path/to/out
*** note Caveat: You need to have enough RAM + swap to back the tmpfs. For a full debug build, you will need about 20 GB. Less for just building the chrome target or for a release build.
Quick and dirty benchmark numbers on a HP Z600 (Intel core i7, 16 cores hyperthreaded, 12 GB RAM)
- With tmpfs:
- 12m:20s
- Without tmpfs
- 15m:40s
The Chrome binary contains embedded symbols by default. You can reduce its size
by using the Linux strip
command to remove this debug information. You can
also reduce binary size by disabling debug mode, disabling dchecks, and turning
on all optimizations by enabling official build mode, with these GN args:
is_debug = false
dcheck_always_on = false
is_official_build = true
Build Chromium (the "chrome" target) with Ninja using the command:
$ autoninja -C out/Default chrome
(autoninja
is a wrapper that automatically provides optimal values for the
arguments passed to ninja
.)
You can get a list of all of the other build targets from GN by running gn ls out/Default
from the command line. To compile one, pass the GN label to Ninja
with no preceding "//" (so, for //chrome/test:unit_tests
use autoninja -C out/Default chrome/test:unit_tests
).
Once it is built, you can simply run the browser:
$ out/Default/chrome
First build the unit_tests binary by running the command:
$ autoninja -C out/Default unit_tests
You can run the tests by running the unit_tests binary. You can also limit which
tests are run using the --gtest_filter
arg, e.g.:
$ out/Default/unit_tests --gtest_filter="PushClientTest.*"
You can find out more about GoogleTest at its GitHub page.
To update an existing checkout, you can run
$ git rebase-update
$ gclient sync
The first command updates the primary Chromium source repository and rebases
any of your local branches on top of tip-of-tree (aka the Git branch
origin/main
). If you don't want to use this script, you can also just use
git pull
or other common Git commands to update the repo.
The second command syncs dependencies to the appropriate versions and re-runs hooks as needed.
If, during the final link stage:
LINK out/Debug/chrome
You get an error like:
collect2: ld terminated with signal 6 Aborted terminate called after throwing an instance of 'std::bad_alloc'
collect2: ld terminated with signal 11 [Segmentation fault], core dumped
you are probably running out of memory when linking. You must use a 64-bit system to build. Try the following build settings (see GN build configuration for other settings):
- Build in release mode (debugging symbols require more memory):
is_debug = false
- Turn off symbols:
symbol_level = 0
- Build in component mode (this is for development only, it will be slower and
may have broken functionality):
is_component_build = true
- Information about building with Clang.
- You may want to use a chroot to isolate yourself from versioning or packaging conflicts.
- Cross-compiling for ARM? See LinuxChromiumArm.
- Want to use Eclipse as your IDE? See LinuxEclipseDev.
- Want to use your built version as your default browser? See LinuxDevBuildAsDefaultBrowser.
If you want to contribute to the effort toward a Chromium-based browser for Linux, please check out the Linux Development page for more information.
Instead of running install-build-deps.sh
to install build dependencies, run:
$ sudo pacman -S --needed python perl gcc gcc-libs bison flex gperf pkgconfig \
nss alsa-lib glib2 gtk3 nspr freetype2 cairo dbus libgnome-keyring \
xorg-server-xvfb xorg-xdpyinfo
For the optional packages on Arch Linux:
php-cgi
is provided withpacman
wdiff
is not in the main repository butdwdiff
is. You can getwdiff
in AUR/yaourt
First install the file
and lsb-release
commands for the script to run properly:
$ sudo apt-get install file lsb-release
Then invoke install-build-deps.sh with the --no-arm
argument,
because the ARM toolchain doesn't exist for this configuration:
$ sudo install-build-deps.sh --no-arm
Instead of running build/install-build-deps.sh
, run:
su -c 'yum install git python bzip2 tar pkgconfig atk-devel alsa-lib-devel \
bison binutils brlapi-devel bluez-libs-devel bzip2-devel cairo-devel \
cups-devel dbus-devel dbus-glib-devel expat-devel fontconfig-devel \
freetype-devel gcc-c++ glib2-devel glibc.i686 gperf glib2-devel \
gtk3-devel java-1.*.0-openjdk-devel libatomic libcap-devel libffi-devel \
libgcc.i686 libgnome-keyring-devel libjpeg-devel libstdc++.i686 libX11-devel \
libXScrnSaver-devel libXtst-devel libxkbcommon-x11-devel ncurses-compat-libs \
nspr-devel nss-devel pam-devel pango-devel pciutils-devel \
pulseaudio-libs-devel zlib.i686 httpd mod_ssl php php-cli python-psutil wdiff \
xorg-x11-server-Xvfb'
The fonts needed by Blink's web tests can be obtained by following these instructions. For the optional packages:
php-cgi
is provided by thephp-cli
package.sun-java6-fonts
is covered by the instructions linked above.
You can just run emerge www-client/chromium
.
Use zypper
command to install dependencies:
(openSUSE 11.1 and higher)
sudo zypper in subversion pkg-config python perl bison flex gperf \
mozilla-nss-devel glib2-devel gtk-devel wdiff lighttpd gcc gcc-c++ \
mozilla-nspr mozilla-nspr-devel php5-fastcgi alsa-devel libexpat-devel \
libjpeg-devel libbz2-devel
For 11.0, use libnspr4-0d
and libnspr4-dev
instead of mozilla-nspr
and
mozilla-nspr-devel
, and use php5-cgi
instead of php5-fastcgi
.
(openSUSE 11.0)
sudo zypper in subversion pkg-config python perl \
bison flex gperf mozilla-nss-devel glib2-devel gtk-devel \
libnspr4-0d libnspr4-dev wdiff lighttpd gcc gcc-c++ libexpat-devel \
php5-cgi alsa-devel gtk3-devel jpeg-devel
The Ubuntu package sun-java6-fonts
contains a subset of Java of the fonts used.
Since this package requires Java as a prerequisite anyway, we can do the same
thing by just installing the equivalent openSUSE Sun Java package:
sudo zypper in java-1_6_0-sun
WebKit is currently hard-linked to the Microsoft fonts. To install these using zypper
sudo zypper in fetchmsttfonts pullin-msttf-fonts
To make the fonts installed above work, as the paths are hardcoded for Ubuntu, create symlinks to the appropriate locations:
sudo mkdir -p /usr/share/fonts/truetype/msttcorefonts
sudo ln -s /usr/share/fonts/truetype/arial.ttf /usr/share/fonts/truetype/msttcorefonts/Arial.ttf
sudo ln -s /usr/share/fonts/truetype/arialbd.ttf /usr/share/fonts/truetype/msttcorefonts/Arial_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/arialbi.ttf /usr/share/fonts/truetype/msttcorefonts/Arial_Bold_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/ariali.ttf /usr/share/fonts/truetype/msttcorefonts/Arial_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/comic.ttf /usr/share/fonts/truetype/msttcorefonts/Comic_Sans_MS.ttf
sudo ln -s /usr/share/fonts/truetype/comicbd.ttf /usr/share/fonts/truetype/msttcorefonts/Comic_Sans_MS_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/cour.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New.ttf
sudo ln -s /usr/share/fonts/truetype/courbd.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/courbi.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New_Bold_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/couri.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/impact.ttf /usr/share/fonts/truetype/msttcorefonts/Impact.ttf
sudo ln -s /usr/share/fonts/truetype/times.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman.ttf
sudo ln -s /usr/share/fonts/truetype/timesbd.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/timesbi.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Bold_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/timesi.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/verdana.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana.ttf
sudo ln -s /usr/share/fonts/truetype/verdanab.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/verdanai.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/verdanaz.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana_Bold_Italic.ttf
The Ubuntu package sun-java6-fonts
contains a subset of Java of the fonts used.
Since this package requires Java as a prerequisite anyway, we can do the same
thing by just installing the equivalent openSUSE Sun Java package:
sudo zypper in java-1_6_0-sun
WebKit is currently hard-linked to the Microsoft fonts. To install these using zypper
sudo zypper in fetchmsttfonts pullin-msttf-fonts
To make the fonts installed above work, as the paths are hardcoded for Ubuntu, create symlinks to the appropriate locations:
sudo mkdir -p /usr/share/fonts/truetype/msttcorefonts
sudo ln -s /usr/share/fonts/truetype/arial.ttf /usr/share/fonts/truetype/msttcorefonts/Arial.ttf
sudo ln -s /usr/share/fonts/truetype/arialbd.ttf /usr/share/fonts/truetype/msttcorefonts/Arial_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/arialbi.ttf /usr/share/fonts/truetype/msttcorefonts/Arial_Bold_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/ariali.ttf /usr/share/fonts/truetype/msttcorefonts/Arial_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/comic.ttf /usr/share/fonts/truetype/msttcorefonts/Comic_Sans_MS.ttf
sudo ln -s /usr/share/fonts/truetype/comicbd.ttf /usr/share/fonts/truetype/msttcorefonts/Comic_Sans_MS_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/cour.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New.ttf
sudo ln -s /usr/share/fonts/truetype/courbd.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/courbi.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New_Bold_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/couri.ttf /usr/share/fonts/truetype/msttcorefonts/Courier_New_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/impact.ttf /usr/share/fonts/truetype/msttcorefonts/Impact.ttf
sudo ln -s /usr/share/fonts/truetype/times.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman.ttf
sudo ln -s /usr/share/fonts/truetype/timesbd.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/timesbi.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Bold_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/timesi.ttf /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/verdana.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana.ttf
sudo ln -s /usr/share/fonts/truetype/verdanab.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana_Bold.ttf
sudo ln -s /usr/share/fonts/truetype/verdanai.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana_Italic.ttf
sudo ln -s /usr/share/fonts/truetype/verdanaz.ttf /usr/share/fonts/truetype/msttcorefonts/Verdana_Bold_Italic.ttf
And then for the Java fonts:
sudo mkdir -p /usr/share/fonts/truetype/ttf-lucida
sudo find /usr/lib*/jvm/java-1.6.*-sun-*/jre/lib -iname '*.ttf' -print \
-exec ln -s {} /usr/share/fonts/truetype/ttf-lucida \;