This reverts commit e63bfca5, now
that Stem has been upgraded to fix the underlying issue.

This is a workaround for https://github.com/torproject/stem/issues/63

When a Travis chutney job fails, use chutney's new "diagnostics.sh" tool
to produce detailed diagnostic output.

Closes ticket 32792.

Putting the slowest jobs first takes full advantage of Travis
concurrency.

Closes 33194.

Part of 33194.

The job was previously set to fast_finish / allow_failure, to
speed up the build.

Closes ticket 33195.

Stop allowing failures on the Travis CI stem tests job. It looks like
all the stem hangs we were seeing are now fixed, but let's make sure we
see them if they happen again.

Closes ticket 33075.

Closes 32240.

We need to set "Sandbox 0", until we fix sandbox errors that are
triggered by Ubuntu Xenial and Bionic. See 32722.

Part of 32240.

NSS:
* test NSS-specific code with -std=gnu99
* use a recent gcc version from the latest Ubuntu image

Chutney:
* use clang, so we keep one clang Linux job
* keep clang on a fast job, so the overall build finishes quickly

Closes ticket 32500 for 0.3.5.

Require C99 standards-conforming code in Travis CI, but allow GNU gcc
extensions. Also activates clang's -Wtypedef-redefinition warnings.

Builds some jobs with -std=gnu99, and some jobs without.

Closes ticket 32500.

This time, we're disabling it because it's the lowest priority job.
(And also slow.)

Part of 32629.

This reverts commit 4c4a0d50.

This reverts commit 511aeba8.

Bionic has a recent coccinelle version, which passes our CI tests.

But Bionic (and Xenial) cause permissions errors for chutney.
We'll fix those in 32240.

Part of 31919.

Closes ticket 32241.

Recent Ubuntu versions have zstd >= 1.1, which is an optional tor build
dependency.

Closes ticket 32242.

This build was added in 0.3.5.

We need to mitigate slow scheduling of Travis macOS jobs.

Closes ticket 32177.

We need to mitigate slow scheduling of Travis macOS jobs.

Closes ticket 32177.

Since Rust on macOS is slow, don't wait for the macOS Rust job to finish.
Instead, split rust into slow rust (macOS) and fast rust (Linux). And
allow the build to finish before slow rust finishes.

Also make sure that we have:
* a Rust build on each platform,
* a Rust build with each compiler, and
* a check on all our Rust builds.

Finally, sort builds: allow fail last, macOS first, slowest first.

Closes 31859 for 0.3.5.

Part of 31859 for 0.3.5.

Since Travis macOS has IPv6 support (and Travis Linux does not), chutney
will now run its IPv6 networks as part of Travis CI.

But since chutney is slow, don't wait for the macOS chutney to finish.
(Travis have fixed the duplicate notification bug in fast_finish. So we
can use fast_finish and allow_failure to finish early. Unfortunately,
allow_failure also means we ignore failures in macOS chutney.)

Also make sure that we have:
* a compile on each platform, with each compiler,
* a check on each platform, and
* a check on each compiler.

Finally, sort builds: allow fail last, macOS first, slowest first.

Closes ticket 30860.
Closes ticket 31859 for 0.2.9.

Part of 31859.

The jobs should be the same, but Travis may display them differently.

Part of 31859.

Frequently, when a patch fails, it has failures in several files.
Using the "-k" flag will let us learn all the compilation errors,
not just the first one that the compiler hits.

Based on a patch by rl1987.

Sebastian Hahn authored Aug 20, 2019 and teor committed Aug 22, 2019

The main build doesn't use HARDENING_OPTIONS, so the exclude shouldn't,
either. Reduces the number of builders by one.

And add some comments about stem

Part of 29280.

Linux is the first item in the os matrix, so we don't need to specify
it under matrix: include: .

Part of 29280.

Part of 29280.

Part of 29280.

Also filter out stem's SocketClosed logs, and fix some nearby comments.

Part of 30591.

And fix some nearby comments.

Part of 30591.

Previously we had "make check" launched whenever DISTCHECK was
false.  Now we'd like to turn it off in a few other circumstances,
like running chutney.  Maybe stem too?

Skip test_rebind when the TOR_SKIP_TEST_REBIND environmental variable
is set.

Skip test_rebind on macOS in Travis builds, because it is unreliable
on macOS on Travis.

Fixes bug 30713; bugfix on 0.3.5.1-alpha.

Allow the test-stem job to fail in Travis, because it sometimes hangs.

Fixes bug 30744; bugfix on 0.3.5.4-alpha.

Closes ticket 30694.

In Travis, make stem log a controller trace to the console.
And tail stem's tor log after failure.

Closes ticket 30591.

See: https://blog.travis-ci.com/2018-11-19-required-linux-infrastructure-migration

See: https://blog.travis-ci.com/2018-11-19-required-linux-infrastructure-migration