| commit | 3030254733f0baae1353b99e72e85babfbf5fbce | [log] [tgz] |
|---|---|---|
| author | Tomasz Śniatowski <tsniatowski@vewd.com> | Mon Feb 15 13:06:30 2021 +0100 |
| committer | Tomasz Śniatowski <tsniatowski@vewd.com> | Mon Feb 22 23:48:58 2021 +0100 |
| tree | 96c06dc3f48c930eb1caa3b468eb00bdbdb308c0 | |
| parent | d0489c3863f6b2a0d0b0e15880217da3fd4e6d8f [diff] |
Add a -t missingdeps tool to detect some classes of build flakes The tool looks for targets that depend on a generated file, but do not properly specify a dependency on the generator. It needs to be run after a successful build, and will list all potential flakes that may have broken the build, but didn't due to accidental build step ordering. The search relies on the correctness of depfile and generator output information, but these are usually easier to get right than dependencies. The errors found can usually be verified as actual build flakes by trying to build the listed problematic files alone in a clean build directory. Such builds usually fail with a compile job lacking a generated file. There is some overlap between this tool and 'gn check', but not everyone uses gn, not everyone using gn uses gn check, and most importantly, gn check is more about modularity, and less about actual build-time deps without flakes. The tool needs to be run after a build completes and depfile data is collected. It may take several seconds to process, up to a dozen or two on a large, chromium-sized build.
Ninja is a small build system with a focus on speed. https://ninja-build.org/
See the manual or doc/manual.asciidoc included in the distribution for background and more details.
Binaries for Linux, Mac, and Windows are available at GitHub. Run ./ninja -h for Ninja help.
Installation is not necessary because the only required file is the resulting ninja binary. However, to enable features like Bash completion and Emacs and Vim editing modes, some files in misc/ must be copied to appropriate locations.
If you're interested in making changes to Ninja, read CONTRIBUTING.md first.
You can either build Ninja via the custom generator script written in Python or via CMake. For more details see the wiki.
./configure.py --bootstrap
This will generate the ninja binary and a build.ninja file you can now use to build Ninja with itself.
cmake -Bbuild-cmake -H. cmake --build build-cmake
The ninja binary will now be inside the build-cmake directory (you can choose any other name you like).
To run the unit tests:
./build-cmake/ninja_test