[INFO] cloning repository https://github.com/Restioson/umthombo
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Restioson/umthombo" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRestioson%2Fumthombo", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRestioson%2Fumthombo'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d327ddc8a85cefd818e280bb6ce63ee08335f54e
[INFO] checking Restioson/umthombo against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRestioson%2Fumthombo" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Restioson/umthombo on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Restioson/umthombo
[INFO] finished tweaking git repo https://github.com/Restioson/umthombo
[INFO] tweaked toml for git repo https://github.com/Restioson/umthombo written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Restioson/umthombo already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Updating git repository `https://github.com/Restioson/flume`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded event-listener v2.4.0
[INFO] [stderr]   Downloaded spinning_top v0.2.2
[INFO] [stderr]   Downloaded loom v0.3.5
[INFO] [stderr]   Downloaded tokio v0.2.22
[INFO] [stderr]   Downloaded barrage v0.2.1
[INFO] [stderr]   Downloaded generator v0.6.22
[INFO] [stderr]   Downloaded spinny v0.2.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d557eb0607718d53f51ce257d8f2c82e0214a240310fda1225a660a049cebf5a
[INFO] running `Command { std: "docker" "start" "-a" "d557eb0607718d53f51ce257d8f2c82e0214a240310fda1225a660a049cebf5a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d557eb0607718d53f51ce257d8f2c82e0214a240310fda1225a660a049cebf5a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d557eb0607718d53f51ce257d8f2c82e0214a240310fda1225a660a049cebf5a", kill_on_drop: false }`
[INFO] [stdout] d557eb0607718d53f51ce257d8f2c82e0214a240310fda1225a660a049cebf5a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7568badbbdab53eb25db2755bfcfdff411d9550103b032d34cf9ef3be019a63f
[INFO] running `Command { std: "docker" "start" "-a" "7568badbbdab53eb25db2755bfcfdff411d9550103b032d34cf9ef3be019a63f", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.21
[INFO] [stderr]    Compiling syn v1.0.41
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]    Compiling proc-macro-nested v0.1.6
[INFO] [stderr]    Compiling proc-macro-hack v0.5.18
[INFO] [stderr]     Checking once_cell v1.4.1
[INFO] [stderr]    Compiling libc v0.2.77
[INFO] [stderr]     Checking pin-project-lite v0.1.7
[INFO] [stderr]     Checking lock_api v0.4.1
[INFO] [stderr]     Checking futures-task v0.3.5
[INFO] [stderr]     Checking spinny v0.2.0
[INFO] [stderr]     Checking umthombo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/lib.rs:32:1
[INFO] [stdout]    |
[INFO] [stdout] 32 | / pin_project! {
[INFO] [stdout] 33 | |     struct SelectedProducer<'a, P: Producer<'a>> {
[INFO] [stdout] 34 | |         producer: &'a P,
[INFO] [stdout] 35 | |         #[pin]
[INFO] [stdout] ...  |
[INFO] [stdout] 39 | |     }
[INFO] [stdout] 40 | | }
[INFO] [stdout]    | |_^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `$crate::__pin_project_internal` which comes from the expansion of the macro `pin_project` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/select2.rs:19:1
[INFO] [stdout]    |
[INFO] [stdout] 19 | / pin_project! {
[INFO] [stdout] 20 | |     pub struct Select2<'p, A, B>
[INFO] [stdout] 21 | |         where A: Producer<'p>,
[INFO] [stdout] 22 | |               B: Producer<'p>
[INFO] [stdout] ...  |
[INFO] [stdout] 30 | |     }
[INFO] [stdout] 31 | | }
[INFO] [stdout]    | |_^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `$crate::__pin_project_internal` which comes from the expansion of the macro `pin_project` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/select3.rs:20:1
[INFO] [stdout]    |
[INFO] [stdout] 20 | / pin_project! {
[INFO] [stdout] 21 | |     pub struct Select3<'p, A, B, C>
[INFO] [stdout] 22 | |         where A: Producer<'p>,
[INFO] [stdout] 23 | |               B: Producer<'p>,
[INFO] [stdout] ...  |
[INFO] [stdout] 34 | |     }
[INFO] [stdout] 35 | | }
[INFO] [stdout]    | |_^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `$crate::__pin_project_internal` which comes from the expansion of the macro `pin_project` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]     Checking tokio v0.2.22
[INFO] [stderr]     Checking pin-project v0.4.23
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]     Checking futures-executor v0.3.5
[INFO] [stderr]     Checking futures v0.3.5
[INFO] [stdout] warning: unused import: `std::future::Future`
[INFO] [stdout]  --> tests/basic.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::future::Future;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Context`, `Poll`
[INFO] [stdout]  --> tests/basic.rs:5:17
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::task::{Poll, Context};
[INFO] [stdout]   |                 ^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::pin::Pin`
[INFO] [stdout]  --> tests/basic.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::pin::Pin;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next`
[INFO] [stdout]   --> tests/basic.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let next = selector.next().await;
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_next`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next`
[INFO] [stdout]   --> tests/basic.rs:13:48
[INFO] [stdout]    |
[INFO] [stdout] 13 |     assert!(matches!(Either2::<(), ()>::A(()), next));
[INFO] [stdout]    |                                                ^^^^ help: if this is intentional, prefix it with an underscore: `_next`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next`
[INFO] [stdout]   --> tests/basic.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let next = selector.next().await;
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_next`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next`
[INFO] [stdout]   --> tests/basic.rs:21:48
[INFO] [stdout]    |
[INFO] [stdout] 21 |     assert!(matches!(Either2::<(), ()>::A(()), next));
[INFO] [stdout]    |                                                ^^^^ help: if this is intentional, prefix it with an underscore: `_next`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next`
[INFO] [stdout]   --> tests/basic.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let next = selector.next().await;
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_next`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next`
[INFO] [stdout]   --> tests/basic.rs:29:52
[INFO] [stdout]    |
[INFO] [stdout] 29 |     assert!(matches!(Either3::<(), (), ()>::B(()), next));
[INFO] [stdout]    |                                                    ^^^^ help: if this is intentional, prefix it with an underscore: `_next`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/lib.rs:32:1
[INFO] [stdout]    |
[INFO] [stdout] 32 | / pin_project! {
[INFO] [stdout] 33 | |     struct SelectedProducer<'a, P: Producer<'a>> {
[INFO] [stdout] 34 | |         producer: &'a P,
[INFO] [stdout] 35 | |         #[pin]
[INFO] [stdout] ...  |
[INFO] [stdout] 39 | |     }
[INFO] [stdout] 40 | | }
[INFO] [stdout]    | |_^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `$crate::__pin_project_internal` which comes from the expansion of the macro `pin_project` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/select2.rs:19:1
[INFO] [stdout]    |
[INFO] [stdout] 19 | / pin_project! {
[INFO] [stdout] 20 | |     pub struct Select2<'p, A, B>
[INFO] [stdout] 21 | |         where A: Producer<'p>,
[INFO] [stdout] 22 | |               B: Producer<'p>
[INFO] [stdout] ...  |
[INFO] [stdout] 30 | |     }
[INFO] [stdout] 31 | | }
[INFO] [stdout]    | |_^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `$crate::__pin_project_internal` which comes from the expansion of the macro `pin_project` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 9 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/select3.rs:20:1
[INFO] [stdout]    |
[INFO] [stdout] 20 | / pin_project! {
[INFO] [stdout] 21 | |     pub struct Select3<'p, A, B, C>
[INFO] [stdout] 22 | |         where A: Producer<'p>,
[INFO] [stdout] 23 | |               B: Producer<'p>,
[INFO] [stdout] ...  |
[INFO] [stdout] 34 | |     }
[INFO] [stdout] 35 | | }
[INFO] [stdout]    | |_^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `$crate::__pin_project_internal` which comes from the expansion of the macro `pin_project` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 11.42s
[INFO] running `Command { std: "docker" "inspect" "7568badbbdab53eb25db2755bfcfdff411d9550103b032d34cf9ef3be019a63f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7568badbbdab53eb25db2755bfcfdff411d9550103b032d34cf9ef3be019a63f", kill_on_drop: false }`
[INFO] [stdout] 7568badbbdab53eb25db2755bfcfdff411d9550103b032d34cf9ef3be019a63f