Roll ahead to fix and update .gni to unbreak shaderc

Roll third_party/spirv-cross/ 5431e1da2..e5d3a6655 (8 commits)

$ git log 5431e1da2..e5d3a6655 --date=short --no-merges --format='%ad %ae %s'
2019-10-07 rharrison Update SPV_VERSION from 1.4 to 1.5
2019-10-07 post Workaround MSVC issue.
2019-10-07 post Do not consider aliased struct types if the master is not a block.
2019-10-07 post Run
2019-10-04 post Do not value compare JSON files for regression purposes.
2019-10-04 post Reflect: Deal with workgroup size being specialization constants.
2019-10-03 frank.richter reference: Update to include workgroup_size
2019-10-03 frank.richter reflection: Write workgroup_size to JSON for compute shaders

Created with:
  roll-dep third_party/spirv-cross

Roll third_party/shaderc/ e849e6783..621605ce2 (10 commits)

$ git log e849e6783..621605ce2 --date=short --no-merges --format='%ad %ae %s'
2019-10-08 rharrison Fix various build issues for chromium & dawn (#835)
2019-10-08 stevenperron Use a better python idiom (#834)
2019-10-08 stevenperron Fix up use of private spirv-tools headers. (#833)
2019-10-07 rharrison Roll spirv-cross ahead and update known_failures to fix build breakage (#831)
2019-10-07 9856269+sarahM0 spvc: Add an empty opt pass (#816)
2019-10-07 9856269+sarahM0 spvc: Add known_invalid file (#823)
2019-10-04 dneto Add support for targeting SPIR-V 1.5 (#822)
2019-10-03 rharrison Revert "Add spvc compiler to returned result (#821)" (#827)
2019-10-03 rharrison Add spvc compiler to returned result (#821)
2019-10-02 rharrison Rolling 4 dependencies (#817)

Created with:
  roll-dep third_party/shaderc

Change-Id: I9e77d5c78eb647c1f117c356306e6dff7613722a
Reviewed-by: Corentin Wallez <>
Commit-Queue: Ryan Harrison <>
2 files changed
tree: ce75e6d52490a0e484d8fce19e985c975fea4c19
  1. .clang-format
  2. .gitattributes
  3. .gitignore
  4. .gn
  8. DEPS
  10. OWNERS
  12. README.chromium
  14. build_overrides/
  15. codereview.settings
  16. dawn.json
  17. dawn_wire.json
  18. docs/
  19. examples/
  20. generator/
  21. infra/
  22. scripts/
  23. src/
  24. third_party/

Dawn, a WebGPU implementation

Dawn (formerly NXT) is an open-source and cross-platform implementation of the work-in-progress WebGPU standard. It exposes a C/C++ API that maps almost one-to-one to the WebGPU IDL and can be managed as part of a larger system such as a Web browser.

Dawn provides several WebGPU building blocks:

  • WebGPU C/C++ headers that applications and other building blocks use.
  • A “native” implementation of WebGPU using platforms' GPU APIs:
    • D3D12 on Windows 10
    • Metal on OSX (and eventually iOS)
    • Vulkan on Windows, Linux (eventually ChromeOS and Android too)
    • OpenGL as best effort where available
  • A client-server implementation of WebGPU for applications that are in a sandbox without access to native drivers

Directory structure

  • dawn.json: description of the API used to drive code generators.
  • examples: examples showing how Dawn is used.
  • generator: code generator for files produces from dawn.json
    • templates: Jinja2 templates for the generator
  • scripts: scripts to support things like continuous testing, build files, etc.
  • src:
    • common: helper code shared between core Dawn libraries and tests/samples
    • dawn_native: native implementation of WebGPU, one subfolder per backend
    • dawn_wire: client-server implementation of WebGPU
    • include: public headers for Dawn
    • tests: internal Dawn tests
      • end2end: WebGPU tests performing GPU operations
      • unittests: unittests and by extension tests not using the GPU
        • validation: WebGPU validation tests not using the GPU (frontend tests)
    • utils: helper code to use Dawn used by tests and samples
  • third_party: directory where dependencies live as well as their buildfiles.

Building Dawn

Dawn uses the Chromium build system and dependency management so you need to install depot_tools and add it to the PATH.

On Linux you need to have the pkg-config command:

# Install pkg-config on Ubuntu
sudo apt-get install pkg-config

Then get the source as follows:

# Clone the repo as "dawn"
git clone dawn && cd dawn

# Bootstrap the gclient configuration
cp scripts/standalone.gclient .gclient

# Fetch external dependencies and toolchains with gclient
gclient sync

Then generate build files using gn args out/Debug or gn args out/Release. A text editor will appear asking build options, the most common option is is_debug=true/false; otherwise gn args out/Release --list shows all the possible options.

Then use ninja -C out/Release to build dawn and for example ./out/Release/dawn_end2end_tests to run the tests.


Please read and follow Dawn doesn‘t have a formal coding style yet, except what’s defined by our clang format style. Overall try to use the same style and convention as code around your change.

If you find issues with Dawn, please feel free to report them on the bug tracker. For other discussions, please post to Dawn's mailing list.


Please see LICENSE.


This is not an officially supported Google product.