[INFO] updating cached repository https://github.com/adambudziak/shuffle
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 22bed45831e9f0bb0ca85f144e6d933d736102e2
[INFO] checking adambudziak/shuffle against master#fdc0011561c6365c596dfd8fa1ef388162bc89c7 for pr-66504-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fadambudziak%2Fshuffle" "/workspace/builds/worker-8/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/adambudziak/shuffle on toolchain fdc0011561c6365c596dfd8fa1ef388162bc89c7
[INFO] running `"/workspace/cargo-home/bin/cargo" "+fdc0011561c6365c596dfd8fa1ef388162bc89c7" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/adambudziak/shuffle
[INFO] finished tweaking git repo https://github.com/adambudziak/shuffle
[INFO] tweaked toml for git repo https://github.com/adambudziak/shuffle written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/adambudziak/shuffle already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+fdc0011561c6365c596dfd8fa1ef388162bc89c7" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] error: the lock file /workspace/builds/worker-8/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/workspace/cargo-home/bin/cargo" "+fdc0011561c6365c596dfd8fa1ef388162bc89c7" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+fdc0011561c6365c596dfd8fa1ef388162bc89c7" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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=forbid" "-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" "+fdc0011561c6365c596dfd8fa1ef388162bc89c7" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] f89cfee9e7aea89f43b3d1dc7e5cac26df7576c16af542b81540982464ebf387
[INFO] running `"docker" "start" "-a" "f89cfee9e7aea89f43b3d1dc7e5cac26df7576c16af542b81540982464ebf387"`
[INFO] [stderr]     Checking bitvec v0.15.2
[INFO] [stderr]     Checking getrandom v0.1.13
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.2
[INFO] [stderr]     Checking shuffle v0.1.3 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `rand::prelude`
[INFO] [stderr]    --> src/irs.rs:209:9
[INFO] [stderr]     |
[INFO] [stderr] 209 |     use rand::prelude::*;
[INFO] [stderr]     |         ^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/irs.rs:218:9
[INFO] [stderr]     |
[INFO] [stderr] 218 |         irs.shuffle(&mut target, &mut rng);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.55s
[INFO] running `"docker" "inspect" "f89cfee9e7aea89f43b3d1dc7e5cac26df7576c16af542b81540982464ebf387"`
[INFO] running `"docker" "rm" "-f" "f89cfee9e7aea89f43b3d1dc7e5cac26df7576c16af542b81540982464ebf387"`
[INFO] [stdout] f89cfee9e7aea89f43b3d1dc7e5cac26df7576c16af542b81540982464ebf387