[INFO] fetching crate prophet 0.4.2...
[INFO] checking prophet-0.4.2 against master#836c31742687ba4e2f857b5b698e1e9e6b67619c for pr-81789
[INFO] extracting crate prophet 0.4.2 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate prophet 0.4.2 on toolchain 836c31742687ba4e2f857b5b698e1e9e6b67619c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate prophet 0.4.2
[INFO] finished tweaking crates.io crate prophet 0.4.2
[INFO] tweaked toml for crates.io crate prophet 0.4.2 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "fetch" "--locked" "--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-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 719d31a26a5649e8e225855d37f3ab5b9ed577bbbbefacaf13e8bdd09f4816b3
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "719d31a26a5649e8e225855d37f3ab5b9ed577bbbbefacaf13e8bdd09f4816b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "719d31a26a5649e8e225855d37f3ab5b9ed577bbbbefacaf13e8bdd09f4816b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "719d31a26a5649e8e225855d37f3ab5b9ed577bbbbefacaf13e8bdd09f4816b3", kill_on_drop: false }`
[INFO] [stdout] 719d31a26a5649e8e225855d37f3ab5b9ed577bbbbefacaf13e8bdd09f4816b3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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=forbid" "-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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] e6dd2a5792874ee7722af1b153435891fea6167fa8a503f138bc799d5eca104c
[INFO] running `Command { std: "docker" "start" "-a" "e6dd2a5792874ee7722af1b153435891fea6167fa8a503f138bc799d5eca104c", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling libc v0.2.93
[INFO] [stderr]     Checking rustc-serialize v0.3.24
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling serde v1.0.125
[INFO] [stderr]    Compiling syn v1.0.70
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling ndarray v0.10.14
[INFO] [stderr]    Compiling serde_derive v1.0.125
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]     Checking log v0.3.9
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking num-traits v0.1.43
[INFO] [stderr]     Checking num-complex v0.1.43
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking num-bigint v0.1.44
[INFO] [stderr]     Checking num-rational v0.1.42
[INFO] [stderr]     Checking num v0.1.42
[INFO] [stderr]     Checking ndarray-rand v0.6.1
[INFO] [stderr]     Checking prophet v0.4.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `to_owned` that must be used
[INFO] [stdout]    --> src/neural_net.rs:418:4
[INFO] [stdout]     |
[INFO] [stdout] 418 |             layer.calculate_output_gradients(expected.view()).to_owned();
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 36.11s
[INFO] running `Command { std: "docker" "inspect" "e6dd2a5792874ee7722af1b153435891fea6167fa8a503f138bc799d5eca104c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e6dd2a5792874ee7722af1b153435891fea6167fa8a503f138bc799d5eca104c", kill_on_drop: false }`
[INFO] [stdout] e6dd2a5792874ee7722af1b153435891fea6167fa8a503f138bc799d5eca104c