[INFO] updating cached repository https://github.com/psFried/roman-numerals-rust
[INFO] running `Command { std: "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", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a5eb19ba0468ee970bf2118998631a74df84ab43
[INFO] testing psFried/roman-numerals-rust against master#8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e for pr-74409
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FpsFried%2Froman-numerals-rust" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/psFried/roman-numerals-rust on toolchain 8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/psFried/roman-numerals-rust
[INFO] finished tweaking git repo https://github.com/psFried/roman-numerals-rust
[INFO] tweaked toml for git repo https://github.com/psFried/roman-numerals-rust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/psFried/roman-numerals-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 755c3a3cab986db2a4d7773c3edce741fddfdfea6d86a4daebdbbb8bfea8cb91
[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" "755c3a3cab986db2a4d7773c3edce741fddfdfea6d86a4daebdbbb8bfea8cb91", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "755c3a3cab986db2a4d7773c3edce741fddfdfea6d86a4daebdbbb8bfea8cb91", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "755c3a3cab986db2a4d7773c3edce741fddfdfea6d86a4daebdbbb8bfea8cb91", kill_on_drop: false }`
[INFO] [stdout] 755c3a3cab986db2a4d7773c3edce741fddfdfea6d86a4daebdbbb8bfea8cb91
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cea6dcbb67f9be6a664800b5af902e4cfcffd5ceabf5675c10850c331ae8ce76
[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" "cea6dcbb67f9be6a664800b5af902e4cfcffd5ceabf5675c10850c331ae8ce76", kill_on_drop: false }`
[INFO] [stderr]    Compiling roman v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0432]: unresolved import `std::slice::SliceConcatExt`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::slice::SliceConcatExt;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ no `SliceConcatExt` in `slice`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function `set_exit_status` in module `std::env`
[INFO] [stdout]   --> src/main.rs:27:15
[INFO] [stdout]    |
[INFO] [stdout] 27 |     std::env::set_exit_status(1);
[INFO] [stdout]    |               ^^^^^^^^^^^^^^^ not found in `std::env`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0425, E0432.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0425`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `roman`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "cea6dcbb67f9be6a664800b5af902e4cfcffd5ceabf5675c10850c331ae8ce76", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cea6dcbb67f9be6a664800b5af902e4cfcffd5ceabf5675c10850c331ae8ce76", kill_on_drop: false }`
[INFO] [stdout] cea6dcbb67f9be6a664800b5af902e4cfcffd5ceabf5675c10850c331ae8ce76