|author||Sylvain Defresne <firstname.lastname@example.org>||Wed Mar 04 16:36:35 2020 +0100|
|committer||Commit Bot <email@example.com>||Wed Mar 04 16:20:01 2020 +0000|
Fix crash in "gn gen --ide=xcode" when project is malformed As found while investigating https://crbug.com/1056925, if the project was malformed, "gn gen --ide=xcode" could crash due to some undefined behaviour (likely dereferencing an uninitialised pointer). This was due to FindApplicationTargetByName() using DCHECK to enforce a property of the project when said property is not under the control of the programmer but under the control of the user writing the project's BUILD.gn files. Instead change the function implementation to return an error if the expected property is not verified. That error is then propagated back to the "gn gen" implementation and displayed to the user. All other uses of DCHECK/NOTREACHED in xcode_writer.cc have been inspected to verify they correspond to assertion about the state of the code and do not depend on the properties of the project's BUILD.gn files. Bug: 150 Change-Id: Ibe711f2d380ef0ed5dca637799563223c248ec7d Reviewed-on: https://gn-review.googlesource.com/c/gn/+/7560 Commit-Queue: Brett Wilson <firstname.lastname@example.org> Reviewed-by: Brett Wilson <email@example.com>
GN is a meta-build system that generates build files for Ninja.
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: out/gn_unittests
On Windows, it is expected that
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
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 ./out/hello
For a maximal configuration see the Chromium setup:
and the Fuchsia setup:
If you find a bug, you can see if it is known or report it in the bug database.
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.