[INFO] fetching crate utils 0.0.3...
[INFO] testing utils-0.0.3 against 1.55.0 for beta-1.56-1
[INFO] extracting crate utils 0.0.3 into /workspace/builds/worker-86/source
[INFO] validating manifest of crates.io crate utils 0.0.3 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate utils 0.0.3
[INFO] finished tweaking crates.io crate utils 0.0.3
[INFO] tweaked toml for crates.io crate utils 0.0.3 written to /workspace/builds/worker-86/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bbde197b70176e3482b48702bc82b9594d359d9578a75bf1c3b39707c8cdd12d
[INFO] running `Command { std: "docker" "start" "-a" "bbde197b70176e3482b48702bc82b9594d359d9578a75bf1c3b39707c8cdd12d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bbde197b70176e3482b48702bc82b9594d359d9578a75bf1c3b39707c8cdd12d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bbde197b70176e3482b48702bc82b9594d359d9578a75bf1c3b39707c8cdd12d", kill_on_drop: false }`
[INFO] [stdout] bbde197b70176e3482b48702bc82b9594d359d9578a75bf1c3b39707c8cdd12d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cca571751e4fe13eed302016086a03aa1ffe0037420229f6ebfc697bbdde02b5
[INFO] running `Command { std: "docker" "start" "-a" "cca571751e4fe13eed302016086a03aa1ffe0037420229f6ebfc697bbdde02b5", kill_on_drop: false }`
[INFO] [stderr]    Compiling commandext v0.1.0
[INFO] [stderr]    Compiling utils v0.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unknown lint: `unstable`
[INFO] [stdout]  --> src/lib.rs:1:10
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![allow(unstable)]
[INFO] [stdout]   |          ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unknown_lints)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/lib.rs:83:3
[INFO] [stdout]    |
[INFO] [stdout] 83 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/lib.rs:77:3
[INFO] [stdout]    |
[INFO] [stdout] 77 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/lib.rs:37:3
[INFO] [stdout]    |
[INFO] [stdout] 37 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/lib.rs:29:3
[INFO] [stdout]    |
[INFO] [stdout] 29 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/lib.rs:13:3
[INFO] [stdout]    |
[INFO] [stdout] 13 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/empty.rs:63:3
[INFO] [stdout]    |
[INFO] [stdout] 63 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/empty.rs:45:3
[INFO] [stdout]    |
[INFO] [stdout] 45 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/empty.rs:37:3
[INFO] [stdout]    |
[INFO] [stdout] 37 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/empty.rs:29:3
[INFO] [stdout]    |
[INFO] [stdout] 29 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/empty.rs:21:3
[INFO] [stdout]    |
[INFO] [stdout] 21 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `experimental` in this scope
[INFO] [stdout]   --> src/empty.rs:14:3
[INFO] [stdout]    |
[INFO] [stdout] 14 | #[experimental]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0609]: no field `output` on type `Output`
[INFO] [stdout]   --> src/lib.rs:17:36
[INFO] [stdout]    |
[INFO] [stdout] 17 |             match str::from_utf8(p.output.as_slice()).unwrap().trim().parse() {
[INFO] [stdout]    |                                    ^^^^^^ unknown field
[INFO] [stdout]    |
[INFO] [stdout]    = note: available fields are: `status`, `stdout`, `stderr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> src/lib.rs:18:17
[INFO] [stdout]    |
[INFO] [stdout] 17 |             match str::from_utf8(p.output.as_slice()).unwrap().trim().parse() {
[INFO] [stdout]    |                   ----------------------------------------------------------- this expression has type `Result<_, _>`
[INFO] [stdout] 18 |                 Some(i) => i,
[INFO] [stdout]    |                 ^^^^^^^ expected enum `Result`, found enum `Option`
[INFO] [stdout]    |
[INFO] [stdout]    = note: expected enum `Result<_, _>`
[INFO] [stdout]               found enum `Option<_>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> src/lib.rs:19:17
[INFO] [stdout]    |
[INFO] [stdout] 17 |             match str::from_utf8(p.output.as_slice()).unwrap().trim().parse() {
[INFO] [stdout]    |                   ----------------------------------------------------------- this expression has type `Result<_, _>`
[INFO] [stdout] 18 |                 Some(i) => i,
[INFO] [stdout] 19 |                 None    => panic!("unable to cast nproc output!"),
[INFO] [stdout]    |                 ^^^^ expected enum `Result`, found enum `Option`
[INFO] [stdout]    |
[INFO] [stdout]    = note: expected enum `Result<_, _>`
[INFO] [stdout]               found enum `Option<_>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0609]: no field `output` on type `Output`
[INFO] [stdout]   --> src/lib.rs:41:54
[INFO] [stdout]    |
[INFO] [stdout] 41 |             let mut res =  String::from_utf8_lossy(o.output.as_slice());
[INFO] [stdout]    |                                                      ^^^^^^ unknown field
[INFO] [stdout]    |
[INFO] [stdout]    = note: available fields are: `status`, `stdout`, `stderr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `as_slice` found for reference `&String` in the current scope
[INFO] [stdout]   --> src/empty.rs:32:14
[INFO] [stdout]    |
[INFO] [stdout] 32 |         self.as_slice().is_empty()
[INFO] [stdout]    |              ^^^^^^^^ method not found in `&String`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 16 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0308, E0599, E0609.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0308`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `utils` due to 17 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "cca571751e4fe13eed302016086a03aa1ffe0037420229f6ebfc697bbdde02b5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cca571751e4fe13eed302016086a03aa1ffe0037420229f6ebfc697bbdde02b5", kill_on_drop: false }`
[INFO] [stdout] cca571751e4fe13eed302016086a03aa1ffe0037420229f6ebfc697bbdde02b5