It's looking like we're still timing out all over the place with travis_wait
because the entire `make -j4 rustc-stage1` command is taking too long. Instead,
achieve roughly the same idea by just having `-Z time-passes` printing
information. We shouldn't have a pass that takes longer than 10 minutes in
isolation.
The most frequent failure for our travis builds is running into the timeout
limits when building the compiler itself. Building librustc takes a very long
amount of time, often hitting the 10 minutes with no output threshold that
travis imposes on us.
This commit switches the relevant `make` step to being wrapped in the
`travis_wait` command [1]. This command will print something once a minute so as
to not time out a build.
This will hopefully enable us to have fewer flaky builds on travis!
[1]: http://docs.travis-ci.com/user/build-timeouts/
This version is slightly more up to date and is closer to the 3.5 that we're
using. This also updates the travis config to have a build matrix which tests
rust against LLVM 3.3 and 3.4. For pull requests only LLVM 3.4 is tested to
reduce the load on travis.
This is mostly just fluff, there's no real reason to gate rust on these results,
it's more of just a nice thing to know when we break compatibility with LLVM 3.3
and 3.4 (and eventually 3.5). This turns off notifications of failed commits
(which are sent out for pushes to master).
Travis CI provides an easy-to-use continuous integration infrastructure for
github repos to use. Travis will automatically test all PRs which are opened
against the rust repository, informing PR owners of the test results.
I believe that this will be a very convenient piece of infrastructure as we'll
be able to reduce the load on bors quite a bit. In theory all PRs opened have
had the full test suite run against them, but unfortunately this is rarely the
case (I'm a prime suspect). Travis will be able to provide easy and relatively
quick (~30min) feedback for PRs. By ensuring fewer failures on bors, we can
hopefully feed more successful jobs to bors.
Overall, I expect this to be very helpful for new contributors as well as
regular contributors as it's another layer of tests being run which will
hopefully catch things sooner. One of the most convenient parts about using
Travis is that there's very little burden in terms of maintenance, and if things
go wrong we can easily turn travis completely off.
Note that this is *not* the metric by which a PR will be merged with. Using
travis will purely be another source for running tests, we will continue to gate
all PRs on bors.