[INFO] cloning repository https://github.com/schulke-214/connect-four
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/schulke-214/connect-four" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fschulke-214%2Fconnect-four"`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fschulke-214%2Fconnect-four'...
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d7ac09027d9e2bd6b2b54f4416ed1da38541c68b
[INFO] checking schulke-214/connect-four against try#e4dba30b9b475d8750370c4dfb49b6541990904d for pr-71393
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fschulke-214%2Fconnect-four" "/workspace/builds/worker-12/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/schulke-214/connect-four on toolchain e4dba30b9b475d8750370c4dfb49b6541990904d
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/schulke-214/connect-four
[INFO] finished tweaking git repo https://github.com/schulke-214/connect-four
[INFO] tweaked toml for git repo https://github.com/schulke-214/connect-four written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/schulke-214/connect-four already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "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-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] beaa00fb967033622f6894123edf5bd5e4e36dc58cc77567b8276d08f5b4f58b
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `"docker" "start" "-a" "beaa00fb967033622f6894123edf5bd5e4e36dc58cc77567b8276d08f5b4f58b"`
[INFO] [stderr]     Checking connect-four v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused return value of `std::string::String::split_off` that must be used
[INFO] [stderr]    --> src/main.rs:498:9
[INFO] [stderr]     |
[INFO] [stderr] 498 |         input.split_off(input.len() - 1);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: use `.truncate()` if you don't need the other half
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::string::String::split_off` that must be used
[INFO] [stderr]    --> src/main.rs:498:9
[INFO] [stderr]     |
[INFO] [stderr] 498 |         input.split_off(input.len() - 1);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: use `.truncate()` if you don't need the other half
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.64s
[INFO] running `"docker" "inspect" "beaa00fb967033622f6894123edf5bd5e4e36dc58cc77567b8276d08f5b4f58b"`
[INFO] running `"docker" "rm" "-f" "beaa00fb967033622f6894123edf5bd5e4e36dc58cc77567b8276d08f5b4f58b"`
[INFO] [stdout] beaa00fb967033622f6894123edf5bd5e4e36dc58cc77567b8276d08f5b4f58b