There are instructions for other platforms linked from the get the code page.
Are you a Google employee? See go/building-chrome-win instead.
As of December 8, 2016 Chromium requires Visual Studio 2015, with the 14393 Windows SDK to build.
Install Visual Studio 2015 Update 3 or later - Community Edition should work if its license is appropriate for you. Use the Custom Install option and select:
You must have the 14393 SDK installed or else you will hit compile errors such as undefined or redefined macros.
Install the Windows SDK 10, and choose Debugging Tools For Windows when you install this in order to get windbg.
depot_toolsDownload the depot_tools bundle and extract it somewhere.
Add depot_tools to the start of your PATH (must be ahead of any installs of Python). Assuming you unzipped the bundle to C:\src\depot_tools, open:
Control Panel → System and Security → System → Advanced system settings
If you have Administrator access, Modify the PATH system variable and put C:\src\depot_tools at the front (or at least in front of any directory that might already have a copy of Python or Git).
If you don't have Administrator access, you can add a user-level PATH environment variable and put C:\src\depot_tools at the front, but if your system PATH has a Python in it, you will be out of luck.
Also, add a DEPOT_TOOLS_WIN_TOOLCHAIN system variable in the same way, and set it to 0. This tells depot_tools to use your locally installed version of Visual Studio (by default, depot_tools will try to use a google-internal version).
From a cmd.exe shell, run the command gclient (without arguments). On first run, gclient will install all the Windows-specific bits needed to work with the code, including msysgit and python.
After running gclient open a command prompt and type where python and confirm that the depot_tools python.bat comes ahead of any copies of python.exe. Failing to ensure this can lead to overbuilding when using gn - see crbug.com/611087.
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 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.
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
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:
$ gn gen out/Default
Default with another name, but it should be a subdirectory of out.gn help on the command line or read the quick start guide.If you want to use the Visual Studio IDE, use the --ide command line argument to gn gen when you generate your output directory (as described on the get the code page):
$ gn gen --ide=vs out\Default $ devenv out\Default\all.sln
GN will produce a file all.sln in your build directory. It will internally use Ninja to compile while still allowing most IDE functions to work (there is no native Visual Studio compilation mode). If you manually run “gen” again you will need to resupply this argument, but normally GN will keep the build and IDE files up to date automatically when you build.
The generated solution will contain several thousand projects and will be very slow to load. Use the --filters argument to restrict generating project files for only the code you're interested in, although this will also limit what files appear in the project explorer. A minimal solution that will let you compile and run Chrome in the IDE but will not show any source files is:
$ gn gen --ide=vs --filters=//chrome out\Default
There are other options for controlling how the solution is generated, run gn help gen for the current documentation.
Still, expect build times of 30 minutes to 2 hours when everything has to be recompiled.
Build Chromium (the “chrome” target) with Ninja using the command:
$ ninja -C out\Default chrome
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 to Ninja the GN label with no preceding “//” (so for //chrome/test:unit_tests use ninja -C out/Default chrome/test:unit_tests`).
Once it is built, you can simply run the browser:
$ out\Default\chrome.exe
(The “.exe” suffix in the command is actually optional).
You can run the tests in the same way. You can also limit which tests are run using the --gtest_filter arg, e.g.:
$ out\Default\unit_tests.exe --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/master). 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 the subrepositories to the appropriate versions and re-runs the hooks as needed.