[INFO] fetching crate fuzzcheck_mutators 0.4.1...
[INFO] checking fuzzcheck_mutators-0.4.1 against master#d62d3f7fa9a91d933213cc10e20e740608983f64 for pr-77015
[INFO] extracting crate fuzzcheck_mutators 0.4.1 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate fuzzcheck_mutators 0.4.1 on toolchain d62d3f7fa9a91d933213cc10e20e740608983f64
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate fuzzcheck_mutators 0.4.1
[INFO] finished tweaking crates.io crate fuzzcheck_mutators 0.4.1
[INFO] tweaked toml for crates.io crate fuzzcheck_mutators 0.4.1 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate crates.io crate fuzzcheck_mutators 0.4.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "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-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f4a8f910fcbbc79a0163df3516c4747ebfdf042e6e5c00e04e1cc7de622b3d55
[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" "f4a8f910fcbbc79a0163df3516c4747ebfdf042e6e5c00e04e1cc7de622b3d55", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f4a8f910fcbbc79a0163df3516c4747ebfdf042e6e5c00e04e1cc7de622b3d55", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f4a8f910fcbbc79a0163df3516c4747ebfdf042e6e5c00e04e1cc7de622b3d55", kill_on_drop: false }`
[INFO] [stdout] f4a8f910fcbbc79a0163df3516c4747ebfdf042e6e5c00e04e1cc7de622b3d55
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 389e59a4c8cefea5c7ed7f76b7c35f67b3b53ba46973575e2420aefa6fe5be13
[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" "389e59a4c8cefea5c7ed7f76b7c35f67b3b53ba46973575e2420aefa6fe5be13", kill_on_drop: false }`
[INFO] [stderr]     Checking fastrand v1.3.4
[INFO] [stderr]    Compiling fuzzcheck_mutators_derive v0.4.0
[INFO] [stderr]     Checking fuzzcheck_mutators v0.4.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `fuzzcheck_mutators::fuzzcheck_derive_mutator`
[INFO] [stdout]  --> examples/vector_u8.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use fuzzcheck_mutators::fuzzcheck_derive_mutator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> examples/derive_struct.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     for i in 0..10 {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.33s
[INFO] running `Command { std: "docker" "inspect" "389e59a4c8cefea5c7ed7f76b7c35f67b3b53ba46973575e2420aefa6fe5be13", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "389e59a4c8cefea5c7ed7f76b7c35f67b3b53ba46973575e2420aefa6fe5be13", kill_on_drop: false }`
[INFO] [stdout] 389e59a4c8cefea5c7ed7f76b7c35f67b3b53ba46973575e2420aefa6fe5be13