[INFO] fetching crate merkle_tree 0.1.0...
[INFO] testing merkle_tree-0.1.0 against 1.55.0 for beta-1.56-1
[INFO] extracting crate merkle_tree 0.1.0 into /workspace/builds/worker-15/source
[INFO] validating manifest of crates.io crate merkle_tree 0.1.0 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 merkle_tree 0.1.0
[INFO] finished tweaking crates.io crate merkle_tree 0.1.0
[INFO] tweaked toml for crates.io crate merkle_tree 0.1.0 written to /workspace/builds/worker-15/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-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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] ef5c02563567427117bfaa346a300f1bc5e4ebeda664581280b4f984c5f7f7c6
[INFO] running `Command { std: "docker" "start" "-a" "ef5c02563567427117bfaa346a300f1bc5e4ebeda664581280b4f984c5f7f7c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ef5c02563567427117bfaa346a300f1bc5e4ebeda664581280b4f984c5f7f7c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ef5c02563567427117bfaa346a300f1bc5e4ebeda664581280b4f984c5f7f7c6", kill_on_drop: false }`
[INFO] [stdout] ef5c02563567427117bfaa346a300f1bc5e4ebeda664581280b4f984c5f7f7c6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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] a73a41490d50ee0f4366031be17c84747f8af1f7d8f50d958d4be76569874f45
[INFO] running `Command { std: "docker" "start" "-a" "a73a41490d50ee0f4366031be17c84747f8af1f7d8f50d958d4be76569874f45", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.101
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]    Compiling proc-macro2 v1.0.29
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling ucd-util v0.1.8
[INFO] [stderr]    Compiling gcc v0.3.55
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]    Compiling utf8-ranges v1.0.4
[INFO] [stderr]    Compiling serde_json v1.0.67
[INFO] [stderr]    Compiling rustc-serialize v0.3.24
[INFO] [stderr]    Compiling itoa v0.4.8
[INFO] [stderr]    Compiling hex-slice v0.1.4
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]    Compiling log v0.3.9
[INFO] [stderr]    Compiling regex-syntax v0.5.6
[INFO] [stderr]    Compiling rust-crypto v0.2.36
[INFO] [stderr]    Compiling crossbeam-channel v0.5.1
[INFO] [stderr]    Compiling aho-corasick v0.6.10
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling time v0.1.44
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling crossbeam-deque v0.8.1
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling num-traits v0.1.43
[INFO] [stderr]    Compiling rmp v0.8.10
[INFO] [stderr]    Compiling rayon v0.7.1
[INFO] [stderr]    Compiling env_logger v0.4.3
[INFO] [stderr]    Compiling rmp-serde v0.13.7
[INFO] [stderr]    Compiling bincode v0.8.0
[INFO] [stderr]    Compiling merkle_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 15.64s
[INFO] running `Command { std: "docker" "inspect" "a73a41490d50ee0f4366031be17c84747f8af1f7d8f50d958d4be76569874f45", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a73a41490d50ee0f4366031be17c84747f8af1f7d8f50d958d4be76569874f45", kill_on_drop: false }`
[INFO] [stdout] a73a41490d50ee0f4366031be17c84747f8af1f7d8f50d958d4be76569874f45
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d5f1b741d91fd5c2205cf6584edc44062550217dd2c404de91e3debc981aa1e8
[INFO] running `Command { std: "docker" "start" "-a" "d5f1b741d91fd5c2205cf6584edc44062550217dd2c404de91e3debc981aa1e8", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling merkle_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> tests/bench_append.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `self::crypto::sha2::Sha256`
[INFO] [stdout]   --> tests/bench_append.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     use self::crypto::sha2::Sha256;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `self::crypto::digest::Digest`
[INFO] [stdout]   --> tests/bench_append.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     use self::crypto::digest::Digest;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> tests/bench_build_tree.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 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 `merkle_tree` due to 2 previous errors; 2 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "d5f1b741d91fd5c2205cf6584edc44062550217dd2c404de91e3debc981aa1e8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d5f1b741d91fd5c2205cf6584edc44062550217dd2c404de91e3debc981aa1e8", kill_on_drop: false }`
[INFO] [stdout] d5f1b741d91fd5c2205cf6584edc44062550217dd2c404de91e3debc981aa1e8