Determine Rust support levels for our targeted platforms

We should go through https://trac.torproject.org/projects/tor/wiki/org/teams/NetworkTeam/SupportedPlatforms and determine how well these platforms are supported by Rust, and then document this information on https://trac.torproject.org/projects/tor/wiki/RustInTor.

changed milestone to %Tor: 0.3.2.x-final

added SponsorZ component::core tor/tor milestone::Tor: 0.3.2.x-final points::.5 priority::medium resolution::worksforme rust severity::normal sponsor::Z status::closed type::task labels

It appears to me that all our "Target" and "Maintained" platforms are in either Tier 1 or 2 on the Rust Platform Support page. (https://forge.rust-lang.org/platform-support.html)

Is there something I'm missing?

Trac:
Status: new to needs_information

64-bit android was mentioned on IRC; what's the status there? Also, I think the current tier 2 guarantees are a bit scary, though they are comparable to our own "maintained" verbiage.

In particular, is the expectation that Tier 2 will generally work well, and that the unit tests, when run, will pass? Or is Tier 2 full of some platforms that work and some that don't?

Replying to isis:

Is there something I'm missing? Those think i686 supports SSE, so don't trust them.

Replying to nickm:

64-bit android was mentioned on IRC; what's the status there? Also, I think the current tier 2 guarantees are a bit scary, though they are comparable to our own "maintained" verbiage.

So the Firefox Treeherder (their CI server) is running tests for aarch64 for Android 5.0 (grep for "Android 5.0 AArch64 opt", e.g. this job). I'm told by the people on the Servo team that all of the tests are running with Rust enabled. Since Firefox is targeting aarch64, there are discussions and general consensus that Rust needs to lift it to Tier 1 support.

In particular, is the expectation that Tier 2 will generally work well, and that the unit tests, when run, will pass? Or is Tier 2 full of some platforms that work and some that don't?

Tier 2 is supposed to build, but the tests are not automatically run. Anecdotally, I (and other people on our team, like ahf, and Firefox/Servo devs, and developers from a company which is using some of my Rust crypto on an HSM) have successfully run the unit tests on Tier 2 platforms without a hitch.

Replying to cypherpunks:

Replying to isis:

Is there something I'm missing? Those lamers

That's not a very excellent thing to say.

think i686 supports SSE, so don't trust them.

It does. In fact, SSE was introduced with the Pentium III, which was the 6th chip in the P6 (a.k.a. i686) microarchitecture series.

In any case, the details of microarchitecture history are pretty moot here, because — in the current draft at least — we consider x86 platforms without SSE2 support to be "unsupported". That is, if you expect Tor (with or without Rust) to run on your Pentium II, it's your job to get a clean patch to us.

Trac:
Milestone: N/A to Tor: 0.3.2.x-final

[Off-topic comment removed by another cypherpunk]

The only disgrace is to treat another person badly.

Trac:
Username: alexcrichton
Cc: N/A to acrichton@mozilla.com

It seems we took this as far as it can go. In summary: rust seems to work anecdotally approximately everywhere that we work anecdotally, and to work testedly where we work testedly.

Trac:
Resolution: N/A to worksforme
Status: needs_information to closed

closed

changed time estimate to 4h

moved to tpo/core/tor#22771 (closed)