[INFO] updating cached repository GHvW/frothy-rs
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/GHvW/frothy-rs
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/GHvW/frothy-rs" "work/ex/beta-1.38-1/sources/1.37.0/gh/GHvW/frothy-rs"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/GHvW/frothy-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/GHvW/frothy-rs" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/GHvW/frothy-rs"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/GHvW/frothy-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] f122bce431b431b33644d4fbc77b4e575cfd4016
[INFO] sha for GitHub repo GHvW/frothy-rs: f122bce431b431b33644d4fbc77b4e575cfd4016
[INFO] validating manifest of GHvW/frothy-rs on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of GHvW/frothy-rs on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing GHvW/frothy-rs
[INFO] finished frobbing GHvW/frothy-rs
[INFO] frobbed toml for GHvW/frothy-rs written to work/ex/beta-1.38-1/sources/1.37.0/gh/GHvW/frothy-rs/Cargo.toml
[INFO] started frobbing GHvW/frothy-rs
[INFO] finished frobbing GHvW/frothy-rs
[INFO] frobbed toml for GHvW/frothy-rs written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/GHvW/frothy-rs/Cargo.toml
[INFO] crate GHvW/frothy-rs already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing GHvW/frothy-rs against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-5/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/GHvW/frothy-rs:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] 1a5a99440463317a250fa2e3ba52f811938cd35fd1aa3e8bba482da8930534cb
[INFO] running `"docker" "start" "-a" "1a5a99440463317a250fa2e3ba52f811938cd35fd1aa3e8bba482da8930534cb"`
[INFO] [stderr]    Compiling frothy_rs v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `Read`
[INFO] [stderr]  --> src/main.rs:3:22
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::io::{Write, Read};
[INFO] [stderr]   |                      ^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error[E0277]: `impl Stack<String>` doesn't implement `std::fmt::Debug`
[INFO] [stderr]   --> src/main.rs:72:37
[INFO] [stderr]    |
[INFO] [stderr] 72 |     println!("current stack: {:?}", *stack);
[INFO] [stderr]    |                                     ^^^^^^ `impl Stack<String>` cannot be formatted using `{:?}` because it doesn't implement `std::fmt::Debug`
[INFO] [stderr]    |
[INFO] [stderr]    = help: the trait `std::fmt::Debug` is not implemented for `impl Stack<String>`
[INFO] [stderr]    = help: consider adding a `where impl Stack<String>: std::fmt::Debug` bound
[INFO] [stderr]    = note: required by `std::fmt::Debug::fmt`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0277`.
[INFO] [stderr] error: Could not compile `frothy_rs`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "1a5a99440463317a250fa2e3ba52f811938cd35fd1aa3e8bba482da8930534cb"`
[INFO] running `"docker" "rm" "-f" "1a5a99440463317a250fa2e3ba52f811938cd35fd1aa3e8bba482da8930534cb"`
[INFO] [stdout] 1a5a99440463317a250fa2e3ba52f811938cd35fd1aa3e8bba482da8930534cb