[INFO] cloning repository https://github.com/learn-you-a-rust/return_values
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/learn-you-a-rust/return_values" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flearn-you-a-rust%2Freturn_values", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flearn-you-a-rust%2Freturn_values'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 909d38d1f4f6cefcc5ba7ce7d8b1454ea4bcabe1
[INFO] testing learn-you-a-rust/return_values against beta-2021-01-01 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flearn-you-a-rust%2Freturn_values" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/learn-you-a-rust/return_values on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/learn-you-a-rust/return_values
[INFO] finished tweaking git repo https://github.com/learn-you-a-rust/return_values
[INFO] tweaked toml for git repo https://github.com/learn-you-a-rust/return_values written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/learn-you-a-rust/return_values already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5c3d837a6638e3ab84ebca0e4750b439a01774915df54762fe5050c92c186f9c
[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" "5c3d837a6638e3ab84ebca0e4750b439a01774915df54762fe5050c92c186f9c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5c3d837a6638e3ab84ebca0e4750b439a01774915df54762fe5050c92c186f9c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5c3d837a6638e3ab84ebca0e4750b439a01774915df54762fe5050c92c186f9c", kill_on_drop: false }`
[INFO] [stdout] 5c3d837a6638e3ab84ebca0e4750b439a01774915df54762fe5050c92c186f9c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 21101f2f16f802c4186f64fe1f7a340d043d378a775bf991ed90ac893b941ed6
[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" "21101f2f16f802c4186f64fe1f7a340d043d378a775bf991ed90ac893b941ed6", kill_on_drop: false }`
[INFO] [stderr]    Compiling return_values v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.08s
[INFO] running `Command { std: "docker" "inspect" "21101f2f16f802c4186f64fe1f7a340d043d378a775bf991ed90ac893b941ed6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21101f2f16f802c4186f64fe1f7a340d043d378a775bf991ed90ac893b941ed6", kill_on_drop: false }`
[INFO] [stdout] 21101f2f16f802c4186f64fe1f7a340d043d378a775bf991ed90ac893b941ed6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9640db3113eaa4b3135f4401c9fa35407fe5b76fec069fbf0e55b2c56614e79f
[INFO] running `Command { std: "docker" "start" "-a" "9640db3113eaa4b3135f4401c9fa35407fe5b76fec069fbf0e55b2c56614e79f", kill_on_drop: false }`
[INFO] [stderr]    Compiling return_values v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.71s
[INFO] running `Command { std: "docker" "inspect" "9640db3113eaa4b3135f4401c9fa35407fe5b76fec069fbf0e55b2c56614e79f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9640db3113eaa4b3135f4401c9fa35407fe5b76fec069fbf0e55b2c56614e79f", kill_on_drop: false }`
[INFO] [stdout] 9640db3113eaa4b3135f4401c9fa35407fe5b76fec069fbf0e55b2c56614e79f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 82cdf15fa5d45c53b26e247b9aa1bc81d55dddf30612398851cccf27ca7669e2
[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" "82cdf15fa5d45c53b26e247b9aa1bc81d55dddf30612398851cccf27ca7669e2", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stdout] running 0 tests
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/return_values-67b2bdeac5ecaf82
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "82cdf15fa5d45c53b26e247b9aa1bc81d55dddf30612398851cccf27ca7669e2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "82cdf15fa5d45c53b26e247b9aa1bc81d55dddf30612398851cccf27ca7669e2", kill_on_drop: false }`
[INFO] [stdout] 82cdf15fa5d45c53b26e247b9aa1bc81d55dddf30612398851cccf27ca7669e2