[INFO] cloning repository https://github.com/terakun/groebner-basis
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/terakun/groebner-basis" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fterakun%2Fgroebner-basis", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fterakun%2Fgroebner-basis'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] bacdd6d1ba0e4704e9dcbf7e774f8b87aeb29503
[INFO] checking terakun/groebner-basis against master#dfd7b8d03fb93d0e03147d28b3be6d93260fa94d for pr-87050
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fterakun%2Fgroebner-basis" "/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/terakun/groebner-basis on toolchain dfd7b8d03fb93d0e03147d28b3be6d93260fa94d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/terakun/groebner-basis
[INFO] finished tweaking git repo https://github.com/terakun/groebner-basis
[INFO] tweaked toml for git repo https://github.com/terakun/groebner-basis written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/terakun/groebner-basis already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "fetch" "--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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] fc5cbb0fc5516693a3b6f6775e55f2b620667abb48e261ea1ad023c30ef2b865
[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" "fc5cbb0fc5516693a3b6f6775e55f2b620667abb48e261ea1ad023c30ef2b865", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fc5cbb0fc5516693a3b6f6775e55f2b620667abb48e261ea1ad023c30ef2b865", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fc5cbb0fc5516693a3b6f6775e55f2b620667abb48e261ea1ad023c30ef2b865", kill_on_drop: false }`
[INFO] [stdout] fc5cbb0fc5516693a3b6f6775e55f2b620667abb48e261ea1ad023c30ef2b865
[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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2797fedd0cea339800398b140ccad81ca2638a94024e55564bd1ee90064173b6
[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" "2797fedd0cea339800398b140ccad81ca2638a94024e55564bd1ee90064173b6", kill_on_drop: false }`
[INFO] [stderr]     Checking groebner-basis v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0463]: can't find crate for `num_rational`
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | extern crate num_rational;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `groebner-basis`
[INFO] [stdout] error[E0463]: can't find crate for `num_rational`
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | extern crate num_rational;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "2797fedd0cea339800398b140ccad81ca2638a94024e55564bd1ee90064173b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2797fedd0cea339800398b140ccad81ca2638a94024e55564bd1ee90064173b6", kill_on_drop: false }`
[INFO] [stdout] 2797fedd0cea339800398b140ccad81ca2638a94024e55564bd1ee90064173b6