[INFO] cloning repository https://github.com/GHvW/frothy-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/GHvW/frothy-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FGHvW%2Ffrothy-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FGHvW%2Ffrothy-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f122bce431b431b33644d4fbc77b4e575cfd4016
[INFO] testing GHvW/frothy-rs against 1.54.0 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FGHvW%2Ffrothy-rs" "/workspace/builds/worker-99/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-99/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/GHvW/frothy-rs on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/GHvW/frothy-rs
[INFO] finished tweaking git repo https://github.com/GHvW/frothy-rs
[INFO] tweaked toml for git repo https://github.com/GHvW/frothy-rs written to /workspace/builds/worker-99/source/Cargo.toml
[INFO] crate git repo https://github.com/GHvW/frothy-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-99/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-99/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c9f4e5b3b7f2bc5429100c03ae2893f7960f501e0175ee03d445d2377aea7732
[INFO] running `Command { std: "docker" "start" "-a" "c9f4e5b3b7f2bc5429100c03ae2893f7960f501e0175ee03d445d2377aea7732", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c9f4e5b3b7f2bc5429100c03ae2893f7960f501e0175ee03d445d2377aea7732", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9f4e5b3b7f2bc5429100c03ae2893f7960f501e0175ee03d445d2377aea7732", kill_on_drop: false }`
[INFO] [stdout] c9f4e5b3b7f2bc5429100c03ae2893f7960f501e0175ee03d445d2377aea7732
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-99/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-99/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=warn" "-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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6672bf14d86a9db3c89755cc8e5c50065180226e97f8356e27e24a4a47221d6a
[INFO] running `Command { std: "docker" "start" "-a" "6672bf14d86a9db3c89755cc8e5c50065180226e97f8356e27e24a4a47221d6a", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling frothy_rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> src/main.rs:3:22
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::io::{Write, Read};
[INFO] [stdout]   |                      ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `impl Stack<String>` doesn't implement `Debug`
[INFO] [stdout]   --> src/main.rs:72:37
[INFO] [stdout]    |
[INFO] [stdout] 72 |     println!("current stack: {:?}", *stack);
[INFO] [stdout]    |                                     ^^^^^^ `impl Stack<String>` cannot be formatted using `{:?}` because it doesn't implement `Debug`
[INFO] [stdout]    |
[INFO] [stdout]    = note: required by `std::fmt::Debug::fmt`
[INFO] [stdout]    = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]    |
[INFO] [stdout] 71 | fn repl(stack: &mut impl Stack<String> + std::fmt::Debug) -> () {
[INFO] [stdout]    |                                        ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `frothy_rs`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "6672bf14d86a9db3c89755cc8e5c50065180226e97f8356e27e24a4a47221d6a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6672bf14d86a9db3c89755cc8e5c50065180226e97f8356e27e24a4a47221d6a", kill_on_drop: false }`
[INFO] [stdout] 6672bf14d86a9db3c89755cc8e5c50065180226e97f8356e27e24a4a47221d6a
