[INFO] cloning repository https://github.com/davidbarsky/trace-prototype
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/davidbarsky/trace-prototype" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavidbarsky%2Ftrace-prototype", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavidbarsky%2Ftrace-prototype'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b14cbdf110c04525d9516a718e4b8b0449b9bfdb
[INFO] checking davidbarsky/trace-prototype against try#0269aeccce4fd29ce9ad0ebd47a62e584d7e25ef for pr-147859
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavidbarsky%2Ftrace-prototype" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/davidbarsky/trace-prototype
[INFO] finished tweaking git repo https://github.com/davidbarsky/trace-prototype
[INFO] tweaked toml for git repo https://github.com/davidbarsky/trace-prototype written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/davidbarsky/trace-prototype on toolchain 0269aeccce4fd29ce9ad0ebd47a62e584d7e25ef
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0269aeccce4fd29ce9ad0ebd47a62e584d7e25ef" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/davidbarsky/trace-prototype 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" "+0269aeccce4fd29ce9ad0ebd47a62e584d7e25ef" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: the cargo feature `edition` has been stabilized in the 1.31 release and is no longer necessary to be listed in the manifest
[INFO] [stderr]   See https://doc.rust-lang.org/nightly/cargo/reference/manifest.html#the-edition-field for more information about using this feature.
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded cc v1.0.22
[INFO] [stderr]   Downloaded cfg-if v0.1.5
[INFO] [stderr]   Downloaded lazy_static v1.1.0
[INFO] [stderr]   Downloaded lock_api v0.1.3
[INFO] [stderr]   Downloaded parking_lot v0.6.3
[INFO] [stderr]   Downloaded crossbeam-deque v0.5.2
[INFO] [stderr]   Downloaded proc-macro2 v0.4.13
[INFO] [stderr]   Downloaded crossbeam-channel v0.2.4
[INFO] [stderr]   Downloaded crossbeam v0.4.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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@sha256:61361fe0aef631f17e9d025a70c5a647956f8c671dd02950a60ad3f5cc5526d7" "/opt/rustwide/cargo-home/bin/cargo" "+0269aeccce4fd29ce9ad0ebd47a62e584d7e25ef" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] efa6afb4e94af74404d7ee2eb30f4fd3395a2cace0898bbba3a2f9d214e23dbf
[INFO] running `Command { std: "docker" "start" "-a" "efa6afb4e94af74404d7ee2eb30f4fd3395a2cace0898bbba3a2f9d214e23dbf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "efa6afb4e94af74404d7ee2eb30f4fd3395a2cace0898bbba3a2f9d214e23dbf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "efa6afb4e94af74404d7ee2eb30f4fd3395a2cace0898bbba3a2f9d214e23dbf", kill_on_drop: false }`
[INFO] [stdout] efa6afb4e94af74404d7ee2eb30f4fd3395a2cace0898bbba3a2f9d214e23dbf
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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@sha256:61361fe0aef631f17e9d025a70c5a647956f8c671dd02950a60ad3f5cc5526d7" "/opt/rustwide/cargo-home/bin/cargo" "+0269aeccce4fd29ce9ad0ebd47a62e584d7e25ef" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2869fa45c8f42d5aa50b02d732b31d3112b2a6c1e3405839c350266053bed067
[INFO] running `Command { std: "docker" "start" "-a" "2869fa45c8f42d5aa50b02d732b31d3112b2a6c1e3405839c350266053bed067", kill_on_drop: false }`
[INFO] [stderr] warning: the cargo feature `edition` has been stabilized in the 1.31 release and is no longer necessary to be listed in the manifest
[INFO] [stderr]   See https://doc.rust-lang.org/nightly/cargo/reference/manifest.html#the-edition-field for more information about using this feature.
[INFO] [stderr]     Checking libc v0.2.43
[INFO] [stderr]    Compiling version_check v0.1.4
[INFO] [stderr]    Compiling proc-macro2 v0.4.13
[INFO] [stderr]     Checking cfg-if v0.1.5
[INFO] [stderr]     Checking scopeguard v0.3.3
[INFO] [stderr]     Checking nodrop v0.1.12
[INFO] [stderr]     Checking stable_deref_trait v1.1.1
[INFO] [stderr]    Compiling cc v1.0.22
[INFO] [stderr]     Checking crossbeam-utils v0.5.0
[INFO] [stderr]     Checking memoffset v0.2.1
[INFO] [stderr]     Checking rand_core v0.2.1
[INFO] [stderr]    Compiling failure_derive v0.1.2
[INFO] [stderr]     Checking rustc-demangle v0.1.9
[INFO] [stderr]     Checking smallvec v0.6.5
[INFO] [stderr]     Checking owning_ref v0.3.3
[INFO] [stderr]     Checking arrayvec v0.4.7
[INFO] [stderr]    Compiling lazy_static v1.1.0
[INFO] [stderr]     Checking rand v0.4.3
[INFO] [stderr]     Checking rand v0.5.5
[INFO] [stderr]     Checking lock_api v0.1.3
[INFO] [stderr]    Compiling quote v0.6.8
[INFO] [stderr]     Checking crossbeam-epoch v0.5.2
[INFO] [stderr]    Compiling backtrace-sys v0.1.24
[INFO] [stderr]    Compiling syn v0.14.9
[INFO] [stderr]     Checking parking_lot_core v0.2.14
[INFO] [stderr]     Checking crossbeam-deque v0.5.2
[INFO] [stderr]     Checking parking_lot v0.6.3
[INFO] [stderr]     Checking crossbeam-channel v0.2.4
[INFO] [stderr]     Checking crossbeam v0.4.1
[INFO] [stderr]     Checking backtrace v0.3.9
[INFO] [stderr]    Compiling synstructure v0.9.0
[INFO] [stderr]     Checking failure v0.1.2
[INFO] [stderr]     Checking trace-prototype v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `channel`
[INFO] [stdout]   --> src/main.rs:15:17
[INFO] [stdout]    |
[INFO] [stdout] 15 | use crossbeam::{channel, queue::SegQueue, Receiver, Sender};
[INFO] [stdout]    |                 ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `channel`
[INFO] [stdout]   --> src/main.rs:15:17
[INFO] [stdout]    |
[INFO] [stdout] 15 | use crossbeam::{channel, queue::SegQueue, Receiver, Sender};
[INFO] [stdout]    |                 ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:24:13
[INFO] [stdout]    |
[INFO] [stdout] 24 | struct Span(String);
[INFO] [stdout]    |        ---- ^^^^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        field in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing this field
[INFO] [stdout]    = note: `Span` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Supervisor` is never used
[INFO] [stdout]   --> src/main.rs:32:7
[INFO] [stdout]    |
[INFO] [stdout] 32 | trait Supervisor {
[INFO] [stdout]    |       ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:24:13
[INFO] [stdout]    |
[INFO] [stdout] 24 | struct Span(String);
[INFO] [stdout]    |        ---- ^^^^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        field in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing this field
[INFO] [stdout]    = note: `Span` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `Channels` is never used
[INFO] [stdout]   --> src/main.rs:36:6
[INFO] [stdout]    |
[INFO] [stdout] 36 | type Channels = Vec<(Sender<Span>, Receiver<Span>)>;
[INFO] [stdout]    |      ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Supervisor` is never used
[INFO] [stdout]   --> src/main.rs:32:7
[INFO] [stdout]    |
[INFO] [stdout] 32 | trait Supervisor {
[INFO] [stdout]    |       ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Super` is never constructed
[INFO] [stdout]   --> src/main.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 | struct Super {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `Channels` is never used
[INFO] [stdout]   --> src/main.rs:36:6
[INFO] [stdout]    |
[INFO] [stdout] 36 | type Channels = Vec<(Sender<Span>, Receiver<Span>)>;
[INFO] [stdout]    |      ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Super` is never constructed
[INFO] [stdout]   --> src/main.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 | struct Super {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main.rs:43:8
[INFO] [stdout]    |
[INFO] [stdout] 42 | impl Super {
[INFO] [stdout]    | ---------- associated function in this implementation
[INFO] [stdout] 43 |     fn new(queue: SegQueue<Span>, channels: Channels) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main.rs:43:8
[INFO] [stdout]    |
[INFO] [stdout] 42 | impl Super {
[INFO] [stdout]    | ---------- associated function in this implementation
[INFO] [stdout] 43 |     fn new(queue: SegQueue<Span>, channels: Channels) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.44s
[INFO] [stderr] warning: the following packages contain code that will be rejected by a future version of Rust: syn v0.14.9
[INFO] [stderr] note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 7`
[INFO] running `Command { std: "docker" "inspect" "2869fa45c8f42d5aa50b02d732b31d3112b2a6c1e3405839c350266053bed067", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2869fa45c8f42d5aa50b02d732b31d3112b2a6c1e3405839c350266053bed067", kill_on_drop: false }`
[INFO] [stdout] 2869fa45c8f42d5aa50b02d732b31d3112b2a6c1e3405839c350266053bed067