[INFO] fetching crate argle 0.1.2...
[INFO] testing argle-0.1.2 against 1.59.0 for beta-1.60-1
[INFO] extracting crate argle 0.1.2 into /workspace/builds/worker-105/source
[INFO] validating manifest of crates.io crate argle 0.1.2 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 crates.io crate argle 0.1.2
[INFO] finished tweaking crates.io crate argle 0.1.2
[INFO] tweaked toml for crates.io crate argle 0.1.2 written to /workspace/builds/worker-105/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "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-105/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-105/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] 68193e4428f1ac76536cd431d53e54931589b2e93fcbaa70beb6e8b49e088d0d
[INFO] running `Command { std: "docker" "start" "-a" "68193e4428f1ac76536cd431d53e54931589b2e93fcbaa70beb6e8b49e088d0d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "68193e4428f1ac76536cd431d53e54931589b2e93fcbaa70beb6e8b49e088d0d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "68193e4428f1ac76536cd431d53e54931589b2e93fcbaa70beb6e8b49e088d0d", kill_on_drop: false }`
[INFO] [stdout] 68193e4428f1ac76536cd431d53e54931589b2e93fcbaa70beb6e8b49e088d0d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-105/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-105/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] a7005be0b9bef9002d81ab4ece11aa3f99c4eb15e30e078a571f356087ee345c
[INFO] running `Command { std: "docker" "start" "-a" "a7005be0b9bef9002d81ab4ece11aa3f99c4eb15e30e078a571f356087ee345c", kill_on_drop: false }`
[INFO] [stderr]    Compiling unicode-width v0.1.9
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling getopts v0.2.21
[INFO] [stderr]    Compiling argle v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(trace_macros)]
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:85:17
[INFO] [stdout]    |
[INFO] [stdout] 85 |                 write!(buf, "Default: {}", d);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:88:17
[INFO] [stdout]    |
[INFO] [stdout] 88 |                 write!(buf, "Dependency: {}", c);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:91:17
[INFO] [stdout]    |
[INFO] [stdout] 91 |                 write!(buf, "Required");
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:108:17
[INFO] [stdout]     |
[INFO] [stdout] 108 |                 write!(buf, "{}", sep);
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:133:17
[INFO] [stdout]     |
[INFO] [stdout] 133 |                 write!(buf, " (");
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:136:17
[INFO] [stdout]     |
[INFO] [stdout] 136 |                 write!(buf, ")");
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 6 warnings 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 `argle` due to 2 previous errors; 6 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "a7005be0b9bef9002d81ab4ece11aa3f99c4eb15e30e078a571f356087ee345c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a7005be0b9bef9002d81ab4ece11aa3f99c4eb15e30e078a571f356087ee345c", kill_on_drop: false }`
[INFO] [stdout] a7005be0b9bef9002d81ab4ece11aa3f99c4eb15e30e078a571f356087ee345c