Latest commit dd7540a Jun 23, 2017 @bors-servo bors-servo committed on GitHub Auto merge of #17472 - moonlightdrive:globalscope-current-option, r=a…

return Option from GlobalScope::current

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handles the case where `GlobalScope::current` calls `CurrentGlobalOrNull` and the result is null

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #17238

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- [X] These changes do not require tests because: no functionality change & ./mach build -d has no errors

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components Auto merge of #17472 - moonlightdrive:globalscope-current-option, r=a… Jun 23, 2017
docs Fix fmt::Display vs fmt::Debug URL Feb 11, 2017
etc Add an index.html page for geckolib docs Jun 12, 2017
ports Auto merge of #17470 - ferjm:bug1336891.customprops.patch, r=emilio Jun 23, 2017
python mach test --all doesn't crash when trying to run tidy. Jun 20, 2017
resources Auto merge of #17037 - cynicaldevil:impl-Sink, r=nox Jun 17, 2017
support Changed the openssl url and bumped the version. Refactored the openss… Jun 12, 2017
tests Auto merge of #17481 - jryans:move-rule-node, r=bholley Jun 23, 2017
.gitattributes Appease Github's Linguist Jun 11, 2015
.gitignore Also ignore orig files. Jun 8, 2017
.hgignore Add .hgignore file Feb 4, 2017
.mailmap Add Gregory Szorc to mail map Jun 21, 2017
.travis.yml Try with enabled `build-geckolib` and `test-stylo` May 8, 2017
CLOBBER Add clobber mechanism May 8, 2017 Start collecting documentation, and add an in-tree glossary. Encourag… Apr 18, 2016
Cargo.lock Auto merge of #17461 - canaltinova:currentcolor, r=emilio Jun 22, 2017
Cargo.toml Update the style crate's bindgen dependency May 8, 2017
Info.plist Package: Restore `run-servo` script on MacOS Jan 6, 2017
LICENSE Add license Apr 4, 2013 Request users to allow edits from maintainers in PRs Mar 23, 2017 Commiting a trivial change for the Firefox sheriffs to test… Jun 21, 2017
appveyor.yml Remove more deprecated Windows GNU code/docs Apr 17, 2017
cargo-commit-hash Update to cargo 0.20.0-nightly (2233f51 2017-05-17) May 18, 2017
dependencyci.yml Don't report the charade package as an error. Jun 18, 2017
mach Disable bytecode generation in mach Apr 10, 2017
mach.bat Add support for Visual Studio 2017 Apr 11, 2017
rust-commit-hash Update Rust nightly to 1.19.0-nightly (2416e222e 2017-06-09) Jun 9, 2017
rust-stable-version Bump rust-stable-version to 1.17. Jun 22, 2017
rustfmt.toml Add rustfmt.toml. Jan 3, 2017
servo-tidy.toml Bring back clipboard support Jun 1, 2017
servobuild.example Disable LLVM assertions by default, on supported platforms. Feb 16, 2017

The Servo Parallel Browser Engine Project

Linux Build Status Windows Build Status Changelog #228

Servo is a web browser engine written in the Rust language. It is currently developed on 64bit OS X, 64bit Linux, and Android.

Servo welcomes contribution from everyone. See and for help getting started.

Visit the Servo Project page for news and guides.

Setting up your environment

Please select your operating system:


On OS X (homebrew)

brew install automake pkg-config python cmake yasm
pip install virtualenv

On OS X (MacPorts)

sudo port install python27 py27-virtualenv cmake yasm

On OS X >= 10.11 (El Capitan), you also have to install OpenSSL

brew install openssl

export OPENSSL_INCLUDE_DIR="$(brew --prefix openssl)/include"
export OPENSSL_LIB_DIR="$(brew --prefix openssl)/lib"

./mach build ...

If you've already partially compiled servo but forgot to do this step, run ./mach clean, set the shell variables, and recompile.

On Debian-based Linuxes

sudo apt install git curl freeglut3-dev autoconf \
    libfreetype6-dev libgl1-mesa-dri libglib2.0-dev xorg-dev \
    gperf g++ build-essential cmake virtualenv python-pip \
    libssl1.0-dev libbz2-dev libosmesa6-dev libxmu6 libxmu-dev \
    libglu1-mesa-dev libgles2-mesa-dev libegl1-mesa-dev libdbus-1-dev

If you using a version prior to Ubuntu 17.04 or Debian Sid, replace libssl1.0-dev with libssl-dev.

If you are on Ubuntu 14.04 and encountered errors on installing these dependencies involving libcheese, see #6158 for a workaround.

If virtualenv does not exist, try python-virtualenv.

On Fedora

sudo dnf install curl freeglut-devel libtool gcc-c++ libXi-devel \
    freetype-devel mesa-libGL-devel mesa-libEGL-devel glib2-devel libX11-devel libXrandr-devel gperf \
    fontconfig-devel cabextract ttmkfdir python python-virtualenv python-pip expat-devel \
    rpm-build openssl-devel cmake bzip2-devel libXcursor-devel libXmu-devel mesa-libOSMesa-devel \
    dbus-devel ncurses-devel

On openSUSE Linux

sudo zypper install libX11-devel libexpat-devel libbz2-devel Mesa-libEGL-devel Mesa-libGL-devel cabextract cmake \
    dbus-1-devel fontconfig-devel freetype-devel gcc-c++ git glib2-devel gperf \
    harfbuzz-devel libOSMesa-devel libXcursor-devel libXi-devel libXmu-devel libXrandr-devel libopenssl-devel \
    python-pip python-virtualenv rpm-build glu-devel

On Arch Linux

sudo pacman -S --needed base-devel git python2 python2-virtualenv python2-pip mesa cmake bzip2 libxmu glu pkg-config

On Gentoo Linux

sudo emerge net-misc/curl media-libs/freeglut \
    media-libs/freetype media-libs/mesa dev-util/gperf \
    dev-python/virtualenv dev-python/pip dev-libs/openssl \
    x11-libs/libXmu media-libs/glu x11-base/xorg-server

On Windows (MSVC)

  1. Install Python for Windows ( The Windows x86-64 MSI installer is fine. You should change the installation to install the "Add python.exe to Path" feature.

  2. Install virtualenv.

In a normal Windows Shell (cmd.exe or "Command Prompt" from the start menu), do:

pip install virtualenv

If this does not work, you may need to reboot for the changed PATH settings (by the python installer) to take effect.

  1. Install Git for Windows ( DO allow it to add git.exe to the PATH (default settings for the installer are fine).

  2. Install Visual Studio 2015 Community Edition ( You MUST add "Visual C++" to the list of installed components. It is not on by default.

Cross-compilation for Android

Pre-installed Android tools are needed. See wiki for details

The Rust compiler

Servo's build system automatically downloads a Rust compiler to build itself. This is normally a specific revision of Rust upstream, but sometimes has a backported patch or two. If you'd like to know which nightly build of Rust we use, see rust-commit-hash.


Servo is built with Cargo, the Rust package manager. We also use Mozilla's Mach tools to orchestrate the build and other tasks.

Normal build

To build Servo in development mode. This is useful for development, but the resulting binary is very slow.

git clone
cd servo
./mach build --dev
./mach run tests/html/about-mozilla.html

Or on Windows MSVC, in a normal Command Prompt (cmd.exe):

git clone
cd servo
mach.bat build --dev

For benchmarking, performance testing, or real-world use, add the --release flag to create an optimized build:

./mach build --release
./mach run --release tests/html/about-mozilla.html

Checking for build errors, without building

If you’re making changes to one crate that cause build errors in another crate, consider this instead of a full build:

./mach check

It will run cargo check, which runs the analysis phase of the compiler (and so shows build errors if any) but skips the code generation phase. This can be a lot faster than a full build, though of course it doesn’t produce a binary you can run.

Building for Android target

git clone
cd servo

export ANDROID_SDK="/path/to/sdk"
export ANDROID_NDK="/path/to/ndk"
export ANDROID_TOOLCHAIN="/path/to/toolchain"
export PATH="$PATH:/path/to/toolchain/bin"

./mach build --release --android
./mach package --release --android

Rather than setting the ANDROID_* environment variables every time, you can also create a .servobuild file and then edit it to contain the correct paths to the Android SDK/NDK tools:

cp servobuild.example .servobuild
# edit .servobuild


Use ./mach run [url] to run Servo. Like so,

./mach run

Also, don't miss the info on the browserhtml page on how to run the Browser.html full tech demo (it provides a more browser-like experience than just browsing a single URL with servo).

Commandline Arguments

  • -p INTERVAL turns on the profiler and dumps info to the console every INTERVAL seconds
  • -s SIZE sets the tile size for painting; defaults to 512
  • -z disables all graphical output; useful for running JS / layout tests
  • -Z help displays useful output to debug servo

Keyboard Shortcuts

  • Ctrl+- zooms out
  • Ctrl+= zooms in
  • Alt+left arrow goes backwards in the history
  • Alt+right arrow goes forwards in the history
  • Esc exits servo


There are lots of mach commands you can use. You can list them with ./mach --help.

The generated documentation can be found on