#summary Build instructions for Linux #labels Linux,build

Overview

Due its complexity, Chromium uses a set of custom tools to check out and build. Here‘s an overview of the steps you’ll run:

  1. gclient. A checkout involves pulling nearly 100 different SVN repositories of code. This process is managed with a tool called gclient.
  2. gyp. The cross-platform build configuration system is called gyp, and on Linux it generates ninja build files. Running gyp is analogous to the ./configure step seen in most other software.
  3. ninja. The actual build itself uses ninja. A prebuilt binary is in depot_tools and should already be in your path if you followed the steps to check out Chromium.
  4. We don't provide any sort of “install” step.
  5. You may want to use a chroot to isolate yourself from versioning or packaging conflicts (or to run the layout tests).

Getting a checkout

Note. If you are working on Chromium OS and already have sources in chromiumos/chromium, you must run chrome_set_ver --runhooks to set the correct dependencies. This step is otherwise performed by gclient as part of your checkout.

First Time Build Bootstrap

  • Make sure your dependencies are up to date by running the install-build-deps.sh script:
.../chromium/src$ build/install-build-deps.sh

gyp (configuring)

After gclient sync finishes, it will run gyp automatically to generate the ninja build files. For standard chromium builds, this automatic step is sufficient and you can start compiling.

To manually configure gyp, run gclient runhooks or run gyp directly via build/gyp_chromium. See Configuring the Build for detailed gyp options.

GypUserDocumentation gives background on gyp, but is not necessary if you are just building Chromium.

Configuring gyp

See Configuring the Build for details; most often you'll be changing the GYP_DEFINES options, which is discussed here.

gyp supports a minimal amount of build configuration via the -D flag.

build/gyp_chromium -Dflag1=value1 -Dflag2=value2

You can store these in the GYP_DEFINES environment variable, separating flags with spaces, as in:

 export GYP_DEFINES="flag1=value1 flag2=value2"

After changing your GYP_DEFINES you need to rerun gyp, either implicitly via gclient sync (which also syncs) or gclient runhooks or explicitly via build/gyp_chromium.

Note that quotes are not necessary for a single flag, but are useful for clarity; GYP_DEFINES=flag1=value1 is syntactically valid but can be confusing compared to GYP_DEFINES="flag1=value1".

If you have various flags for various purposes, you may find it more legible to break them up across several lines, taking care to include spaces, such as like this:

 export GYP_DEFINES="flag1=value1"\
 " flag2=value2"

or like this (allowing comments):

 export GYP_DEFINES="flag1=value1" # comment
 GYP_DEFINES+=" flag2=value2" # another comment

Sample configurations

  • gcc warnings. By default we fail to build if there are any compiler warnings. If you‘re getting warnings, can’t build because of that, but just want to get things done, you can specify -Dwerror= to turn that off:
# one-off
build/gyp_chromium -Dwerror=
# via variable
export GYP_DEFINES="werror="
build/gyp_chromium
  • ChromeOS. -Dchromeos=1 builds the ChromeOS version of Chrome. This is not all of ChromeOS (see the ChromiumOS page for full build instructions), this is just the slightly tweaked version of the browser that runs on that system. Its not designed to be run outside of ChromeOS and some features won't work, but compiling on your Linux desktop can be useful for certain types of development and testing.
# one-off
build/gyp_chromium -Dchromeos=1
# via variable
export GYP_DEFINES="chromeos=1"
build/gyp_chromium

Compilation

The weird “src/” directory is an artifact of gclient. Start with:

$ cd src

Build just chrome

$ ninja -C out/Debug chrome

Faster builds

See LinuxFasterBuilds

Build every test

$ ninja -C out/Debug

The above builds all libraries and tests in all components. It will take hours.

Specifying other target names to restrict the build to just what you're interested in. To build just the simplest unit test:

$ ninja -C out/Debug base_unittests

Clang builds

Information about building with Clang can be found here.

Output

Executables are written in src/out/Debug/ for Debug builds, and src/out/Release/ for Release builds.

Release mode

Pass -C out/Release to the ninja invocation:

$ ninja -C out/Release chrome

Seeing the commands

If you want to see the actual commands that ninja is invoking, add -v to the ninja invocation.

$ ninja -v -C out/Debug chrome

This is useful if, for example, you are debugging gyp changes, or otherwise need to see what ninja is actually doing.

Clean builds

All built files are put into the out/ directory, so to start over with a clean build, just

rm -rf out

and run gclient runhooks or build\gyp_chromium again to recreate the ninja build files (which are also stored in out/). Or you can run ninja -C out/Debug -t clean.

Linker Crashes

If, during the final link stage:

  LINK(target) 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. Try one of:

  1. Use the gold linker
  2. Build on a 64-bit computer
  3. Build in Release mode (debugging symbols require a lot of memory)
  4. Build as shared libraries (note: this build is for developers only, and may have broken functionality) Most of these are described on the LinuxFasterBuilds page.

Advanced Features

  • Building frequently? See LinuxFasterBuilds.
  • Cross-compiling for ARM? See LinuxChromiumArm.
  • Want to use Eclipse as your IDE? See LinuxEclipseDev.
  • Built version as Default Browser? See LinuxDevBuildAsDefaultBrowser.

Next Steps

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.