[INFO] cloning repository https://github.com/statianzo/imposters
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/statianzo/imposters" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fstatianzo%2Fimposters", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fstatianzo%2Fimposters'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 344a5027ba57464a424c1906376445b6e208cb57
[INFO] testing statianzo/imposters against 1.59.0 for beta-1.60-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fstatianzo%2Fimposters" "/workspace/builds/worker-28/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-28/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/statianzo/imposters on toolchain 1.59.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/statianzo/imposters
[INFO] finished tweaking git repo https://github.com/statianzo/imposters
[INFO] tweaked toml for git repo https://github.com/statianzo/imposters written to /workspace/builds/worker-28/source/Cargo.toml
[INFO] crate git repo https://github.com/statianzo/imposters already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-28/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-28/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6ed6a87e67ec2a96b98ad27c452e54b2e0fef7a1fa4a170ea89872b80fba6afe
[INFO] running `Command { std: "docker" "start" "-a" "6ed6a87e67ec2a96b98ad27c452e54b2e0fef7a1fa4a170ea89872b80fba6afe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6ed6a87e67ec2a96b98ad27c452e54b2e0fef7a1fa4a170ea89872b80fba6afe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6ed6a87e67ec2a96b98ad27c452e54b2e0fef7a1fa4a170ea89872b80fba6afe", kill_on_drop: false }`
[INFO] [stdout] 6ed6a87e67ec2a96b98ad27c452e54b2e0fef7a1fa4a170ea89872b80fba6afe
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-28/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-28/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 411cf1614b4724ca6a6b2fb9446863bc22c0add9b85bc5cff00e67515eb08ee0
[INFO] running `Command { std: "docker" "start" "-a" "411cf1614b4724ca6a6b2fb9446863bc22c0add9b85bc5cff00e67515eb08ee0", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling imposters v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.38s
[INFO] running `Command { std: "docker" "inspect" "411cf1614b4724ca6a6b2fb9446863bc22c0add9b85bc5cff00e67515eb08ee0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "411cf1614b4724ca6a6b2fb9446863bc22c0add9b85bc5cff00e67515eb08ee0", kill_on_drop: false }`
[INFO] [stdout] 411cf1614b4724ca6a6b2fb9446863bc22c0add9b85bc5cff00e67515eb08ee0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-28/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-28/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0bbfc640d8cbe39d39e5a3deb34951efddb182248f24a207fe977610d19c4aa8
[INFO] running `Command { std: "docker" "start" "-a" "0bbfc640d8cbe39d39e5a3deb34951efddb182248f24a207fe977610d19c4aa8", kill_on_drop: false }`
[INFO] [stderr]    Compiling regex v1.0.1
[INFO] [stderr]    Compiling lazy_static v1.0.1
[INFO] [stderr]    Compiling quick-error v1.2.2
[INFO] [stderr]    Compiling memchr v2.0.1
[INFO] [stderr]    Compiling atty v0.2.10
[INFO] [stderr]    Compiling rand v0.4.2
[INFO] [stderr]    Compiling regex-syntax v0.6.1
[INFO] [stderr]    Compiling log v0.4.3
[INFO] [stderr]    Compiling rand v0.5.3
[INFO] [stderr]    Compiling thread_local v0.3.5
[INFO] [stderr]    Compiling humantime v1.1.1
[INFO] [stderr]    Compiling aho-corasick v0.6.5
[INFO] [stderr]    Compiling env_logger v0.5.10
[INFO] [stderr]    Compiling quickcheck v0.6.2
[INFO] [stderr]    Compiling imposters v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:27
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(test, feature(test))]
[INFO] [stdout]   |                           ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021
[INFO] [stdout]   --> src/ch08_adv_algs/fib.rs:78:26
[INFO] [stdout]    |
[INFO] [stdout] 78 |         let mut iter = a.into_iter();
[INFO] [stdout]    |                          ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]    = warning: this changes meaning in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]    |
[INFO] [stdout] 78 |         let mut iter = a.iter();
[INFO] [stdout]    |                          ~~~~
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]    |
[INFO] [stdout] 78 |         let mut iter = IntoIterator::into_iter(a);
[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 E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `imposters` due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "0bbfc640d8cbe39d39e5a3deb34951efddb182248f24a207fe977610d19c4aa8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0bbfc640d8cbe39d39e5a3deb34951efddb182248f24a207fe977610d19c4aa8", kill_on_drop: false }`
[INFO] [stdout] 0bbfc640d8cbe39d39e5a3deb34951efddb182248f24a207fe977610d19c4aa8