Switch remaining stamp targets to phony targets

GN uses stamp files for a variety of output types as a mechanism for
completing a group of dependencies. Ninja's phony targets can be used in
a similar manner.

The GN 'group', 'generated_file', 'bundle_data', 'copy', 'action',
'action_for_each' and 'create_bundle' output types each generate a stamp
file as an output for other targets to depend on. This CL replaces those
stamp targets with a phony alias target.

For a few target types, GN optionally creates a "<target>.inputdeps"
and/or "<target>.input" stamp files to represent a group of input
dependencies or inputs, respectively. This is useful for limiting the
size of ninja files because the dependencies only have to be listed
once. As with the stamp files generated for the aforementioned output
types, this CL also replaces those stamp targets with a phony alias

Finally, there are several intermediate stamp files that are created for
certain outputs, such as the code signing stamp for `create_bundle`
targets. Where possible, these are also replaced with phony alias

Bug: 186, 188, 191, 194
Change-Id: I5b257147affc55bb8b093a3f39c7e9a5b56b6f6c
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/10100
Commit-Queue: Brett Wilson <brettw@chromium.org>
Reviewed-by: Brett Wilson <brettw@chromium.org>
31 files changed
tree: f8739ec49a01c221b47d816358dada4800537c98
  1. build/
  2. docs/
  3. examples/
  4. infra/
  5. misc/
  6. src/
  7. tools/
  8. .clang-format
  9. .editorconfig
  10. .gitignore
  11. .style.yapf
  14. OWNERS
  15. README.md


GN is a meta-build system that generates build files for Ninja.

Related resources:

Getting a binary

You can download the latest version of GN binary for Linux, macOS and Windows.

Alternatively, you can build GN from source:

git clone https://gn.googlesource.com/gn
cd gn
python build/gen.py
ninja -C out
# To run tests:

On Windows, it is expected that cl.exe, link.exe, and lib.exe can be found in PATH, so you'll want to run from a Visual Studio command prompt, or similar.

On Linux and Mac, the default compiler is clang++, a recent version is expected to be found in PATH. This can be overridden by setting CC, CXX, and AR.


There is a simple example in examples/simple_build directory that is a good place to get started with the minimal configuration.

To build and run the simple example with the default gcc compiler:

cd examples/simple_build
../../out/gn gen -C out
ninja -C out

For a maximal configuration see the Chromium setup:

and the Fuchsia setup:

Reporting bugs

If you find a bug, you can see if it is known or report it in the bug database.

Sending patches

GN uses Gerrit for code review. The short version of how to patch is:

Register at https://gn-review.googlesource.com.

... edit code ...
ninja -C out && out/gn_unittests

Then, to upload a change for review:

git commit
git push origin HEAD:refs/for/master

The first time you do this you'll get an error from the server about a missing change-ID. Follow the directions in the error message to install the change-ID hook and run git commit --amend to apply the hook to the current commit.

When revising a change, use:

git commit --amend
git push origin HEAD:refs/for/master

which will add the new changes to the existing code review, rather than creating a new one.

We ask that all contributors sign Google's Contributor License Agreement (either individual or corporate as appropriate, select ‘any other Google project’).


You may ask questions and follow along with GN‘s development on Chromium’s gn-dev@ Google Group.