Windows Build Instructions

Setting up Windows

You must set your Windows system locale to English, or else you may get build errors about “The file contains a character that cannot be represented in the current code page.”

Setting up the environment for Visual Studio

You must build with Visual Studio 2015 Update 2; no other version is supported.

You must have Windows 7 x64 or later. x86 OSs are unsupported.

Step 1: Getting depot_tools

Get depot_tools.

Step 2: Getting the compiler toolchain

Follow the appropriate path below:

Open source contributors

As of March 11, 2016 Chromium requires Visual Studio 2015 to build.

Install Visual Studio 2015 Update 2 or later - Community Edition should work if its license is appropriate for you. Use the Custom Install option and select:

  • Visual C++, which will select three sub-categories including MFC
  • Universal Windows Apps Development Tools > Tools
  • Universal Windows Apps Development Tools > Windows 10 SDK (10.0.10586)

You must have the 10586 SDK installed or else you will hit compile errors such as redefined macros.

Run set DEPOT_TOOLS_WIN_TOOLCHAIN=0, or set that variable in your global environment.

Compilation is done through ninja, not Visual Studio.

Google employees

Run: download_from_google_storage --config and follow the authentication instructions. Note that you must authenticate with your @google.com credentials, not @chromium.org. Enter “0” if asked for a project-id.

Once you've done this, the toolchain will be installed automatically for you in Step 3, below (near the end of the step).

The toolchain will be in depot_tools\win_toolchain\vs_files\<hash>, and windbg can be found in depot_tools\win_toolchain\vs_files\<hash>\win_sdk\Debuggers.

If you want the IDE for debugging and editing, you will need to install it separately, but this is optional and not needed to build Chromium.

Step 3: Getting the Code

Follow the steps to check out the code (largely fetch chromium).

Step 4: Building

Build the target you are interested in.

ninja -C out\Debug chrome

Alternative (Graphical user interface): Open a generated .sln file such as chrome.sln, right-click the chrome project and select build. This will invoke the real step 4 above. Do not build the whole solution since that conflicts with ninja's build management and everything will explode. Substitute the build directory given to -C with out\Debug_x64 for 64-bit builds in GYP, or whatever build directory you have configured if using GN.

Performance tips

  1. Have a lot of fast CPU cores and enough RAM to keep them all busy. (Minimum recommended is 4-8 fast cores and 16-32 GB of RAM)
  2. Reduce file system overhead by excluding build directories from antivirus and indexing software.
  3. Store the build tree on a fast disk (preferably SSD).
  4. If you are primarily going to be doing debug development builds, you should use the component build:
    • for GYP set GYP_DEFINES=component=shared_library
    • for GN, set the build arg is_component_build = true. This will generate many DLLs and enable incremental linking, which makes linking much faster in Debug.

Still, expect build times of 30 minutes to 2 hours when everything has to be recompiled.