Ralph Giles (:rillian) Reporter
	Description • 6 years ago

Test builds with rust 1.24 beta toolchains fail pretty universally in the try pushes I've done, usually with a trait bound error in slog or something similar in another crate:

> error[E0277]: the trait bound `*mut core::ops::Fn() + 'static: core::marker::Sync` is not satisfied in `core::fmt::Arguments<'static>`
>    --> /builds/worker/workspace/build/src/third_party/rust/slog/src/ser.rs:228:6
>     |
> 228 | impl SyncSerialize for fmt::Arguments<'static> {}
>     |      ^^^^^^^^^^^^^ `*mut core::ops::Fn() + 'static` cannot be shared between threads safely
>     |
>     = help: within `core::fmt::Arguments<'static>`, the trait `core::marker::Sync` is not implemented for `*mut core::ops::Fn() + 'static`
>     = note: required because it appears within the type `core::marker::PhantomData<*mut core::ops::Fn() + 'static>`
>     = note: required because it appears within the type `core::fmt::Void`
>     = note: required because it appears within the type `&'static core::fmt::Void`
>     = note: required because it appears within the type `core::fmt::ArgumentV1<'static>`
>     = note: required because it appears within the type `[core::fmt::ArgumentV1<'static>]`
>     = note: required because it appears within the type `&'static [core::fmt::ArgumentV1<'static>]`
>     = note: required because it appears within the type `core::fmt::Arguments<'static>`
> error: aborting due to previous error
> error: Could not compile `slog`.
> Caused by:
>   process didn't exit successfully: `/builds/worker/workspace/build/src/sccache2/sccache /builds/worker/workspace/build/src/rustc/bin/rustc --crate-name slog /builds/worker/workspace/build/src/third_party/rust/slog/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 --cfg feature="default" --cfg feature="std" -C metadata=d5e9d36edc8d74c4 -C extra-filename=-d5e9d36edc8d74c4 --out-dir /builds/worker/workspace/build/src/obj-firefox/testing/geckodriver/./x86_64-unknown-linux-gnu/debug/deps --target x86_64-unknown-linux-gnu -C linker=/builds/worker/workspace/build/src/build/cargo-linker -L dependency=/builds/worker/workspace/build/src/obj-firefox/testing/geckodriver/./x86_64-unknown-linux-gnu/debug/deps -L dependency=/builds/worker/workspace/build/src/obj-firefox/testing/geckodriver/./debug/deps --cap-lints allow -C opt-level=2 -C debuginfo=2` (exit code: 101)
> warning: build failed, waiting for other jobs to finish...

I cannot reproduce the failure in local builds, so it must be something with the automation environment or config.

	Nathan Froyd [:froydnj]
	Comment 1 • 6 years ago

Does it reproduce locally if you --enable-rust-simd?

	Ralph Giles (:rillian) Reporter
	Comment 2 • 6 years ago

Ah, I *can* reproduce by running 'cargo build' in third_party/rust/slog which is version 1.6.0. The current version is 2.1.1, which doesn't show the problem. Looks like it didn't show up in my local tests because it's a geckodriver dep. Hopefully we can just update slog.

	Ralph Giles (:rillian) Reporter
	Comment 3 • 6 years ago

(In reply to Nathan Froyd [:froydnj] from comment #1)
> Does it reproduce locally if you --enable-rust-simd?

That was my first thought too, but we're not so unlucky. --enable-geckodriver reproduces.

	Ralph Giles (:rillian) Reporter
	Comment 5 • 6 years ago

Andreas, I started a patch to bump slog, but geckodriver needs updating for the API changes. Do you might looking? It would be great if we could get this resolved before the Rust 1.24 stable release next week.

	Andreas Tolfsen ❲:ato❳ Assignee
	Comment 6 • 6 years ago

Thanks for the heads up, :rillian.  Since I added slog to
geckodriver I have thought it an unnecessarily complicated
dependency.  We use it only for changing the log level at runtime,
which is a requirement to geckodriver due to the moz:firefoxOptions
log level capability [1].

Instead of spending more time trying to figure out how to adapt
geckodriver to the new slog APIs I would like to remove the
dependency altogether.  I’ve filed https://bugzil.la/1436830 to
take care of this.

  [1] https://github.com/mozilla/geckodriver#log-object

	Andreas Tolfsen ❲:ato❳ Assignee
	Comment 7 • 6 years ago

This should now be fixed by removing the slog dependency in bug 1436830.  Happy times.