[INFO] fetching crate merkle_tree 0.1.0...
[INFO] testing merkle_tree-0.1.0 against 1.44.0 for beta-1.45-1
[INFO] extracting crate merkle_tree 0.1.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate merkle_tree 0.1.0 on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[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-9/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 949b726753614f4fc08698bf6661b7122efd36c063b7a05aa305f206e3e7aff8
[INFO] running `"docker" "start" "-a" "949b726753614f4fc08698bf6661b7122efd36c063b7a05aa305f206e3e7aff8"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling gcc v0.3.55
[INFO] [stderr]    Compiling rustc-serialize v0.3.24
[INFO] [stderr]    Compiling hex-slice v0.1.4
[INFO] [stderr]    Compiling num-traits v0.1.43
[INFO] [stderr]    Compiling rmp v0.8.9
[INFO] [stderr]    Compiling crossbeam-queue v0.2.2
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling bincode v0.8.0
[INFO] [stderr]    Compiling rayon-core v1.7.0
[INFO] [stderr]    Compiling rmp-serde v0.13.7
[INFO] [stderr]    Compiling rayon v0.7.1
[INFO] [stderr]    Compiling rust-crypto v0.2.36
[INFO] [stderr]    Compiling merkle_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 18.91s
[INFO] running `"docker" "inspect" "949b726753614f4fc08698bf6661b7122efd36c063b7a05aa305f206e3e7aff8"`
[INFO] running `"docker" "rm" "-f" "949b726753614f4fc08698bf6661b7122efd36c063b7a05aa305f206e3e7aff8"`
[INFO] [stdout] 949b726753614f4fc08698bf6661b7122efd36c063b7a05aa305f206e3e7aff8
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "test" "--frozen" "--no-run"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 4e82ad902644f226ced6129d9cb6bab6bba6abfa720d4bb59d2852764448b10f
[INFO] running `"docker" "start" "-a" "4e82ad902644f226ced6129d9cb6bab6bba6abfa720d4bb59d2852764448b10f"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling merkle_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> tests/bench_append.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(test)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `self::crypto::sha2::Sha256`
[INFO] [stderr]   --> tests/bench_append.rs:13:9
[INFO] [stderr]    |
[INFO] [stderr] 13 |     use self::crypto::sha2::Sha256;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `self::crypto::digest::Digest`
[INFO] [stderr]   --> tests/bench_append.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     use self::crypto::digest::Digest;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> tests/bench_build_tree.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(test)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error; 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `merkle_tree`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `merkle_tree`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "4e82ad902644f226ced6129d9cb6bab6bba6abfa720d4bb59d2852764448b10f"`
[INFO] running `"docker" "rm" "-f" "4e82ad902644f226ced6129d9cb6bab6bba6abfa720d4bb59d2852764448b10f"`
[INFO] [stdout] 4e82ad902644f226ced6129d9cb6bab6bba6abfa720d4bb59d2852764448b10f