Everything is on fire on the CI because this fails to work on servo-mac5 for some
stupid reason. Let's avouid the issue for now because we need to be able to work.
Move global CI environment variables to servo
Migrate RUST_BACKTRACE out of saltfs.
SCCACHE_IDLE_TIMEOUT has already been migrated.
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Re-enable sccache for Linux builds
As far as I know, sccache is working properly
on the non-cross-compiling Linux builders.
For safety, only enable it for the builders that run on PRs,
to avoid breaking our nightly generation and scheduled test runs.
This will also allow testing new versions of sccache more easily.
This implements my suggestion from https://github.com/servo/servo/pull/19858#issuecomment-360514782, and should also let us
handle testing a new sccache: https://github.com/rust-lang/rust/issues/42867#issuecomment-358692077 (our current version of sccache [seems to be 2018-01-09](f50214b8fa/servo-build-dependencies/ci-map.jinja (L5))).
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- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).
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Originally, buildbot would try to directly execute `RUSTFLAGS=` as a binary
since it was the first token in the command string, which won't work.
Fix this by using the `env` command to set the environment variables,
as there is currently no support for setting per-step environment variables
in the `buildbot_steps.yml` file.
As far as I know, sccache is working properly
on the non-cross-compiling Linux builders.
For safety, only enable it for the builders that run on PRs,
to avoid breaking our nightly generation and scheduled test runs.
This will also allow testing new versions of sccache more easily.
Add script to automate pulling changes from upstream WPT.
I want to make automated WPT syncing happen this quarter. This script should allow us to run a nightly job on the builder that grabs the latest changes from upstream runs our testsuite, updates the expected test results, then open a PR with the changes. It still requires saltfs changes to allow it to actually run, but I don't see any harm in getting it reviewed and merged before everything is ready.
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