[INFO] cloning repository https://github.com/ezhang7423/understanding-borrowing
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ezhang7423/understanding-borrowing" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fezhang7423%2Funderstanding-borrowing", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fezhang7423%2Funderstanding-borrowing'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 03a3795c2b9e976093ec6a7bca7f8a1b65424247
[INFO] testing ezhang7423/understanding-borrowing against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fezhang7423%2Funderstanding-borrowing" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ezhang7423/understanding-borrowing on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/ezhang7423/understanding-borrowing
[INFO] finished tweaking git repo https://github.com/ezhang7423/understanding-borrowing
[INFO] tweaked toml for git repo https://github.com/ezhang7423/understanding-borrowing written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/ezhang7423/understanding-borrowing already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5d5f070c684575287b3159d61c90f86745be55e1be8928739eab438a9635113a
[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" "5d5f070c684575287b3159d61c90f86745be55e1be8928739eab438a9635113a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5d5f070c684575287b3159d61c90f86745be55e1be8928739eab438a9635113a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5d5f070c684575287b3159d61c90f86745be55e1be8928739eab438a9635113a", kill_on_drop: false }`
[INFO] [stdout] 5d5f070c684575287b3159d61c90f86745be55e1be8928739eab438a9635113a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 98bcebb3a6a659ade6545bd0a3740346262cc31a3ca34b65d1627a7f75636f99
[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" "98bcebb3a6a659ade6545bd0a3740346262cc31a3ca34b65d1627a7f75636f99", kill_on_drop: false }`
[INFO] [stderr]    Compiling understanding-borrowing v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `y` is never read
[INFO] [stdout]  --> src/main.rs:3:13
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let mut y = x;
[INFO] [stdout]   |             ^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.78s
[INFO] running `Command { std: "docker" "inspect" "98bcebb3a6a659ade6545bd0a3740346262cc31a3ca34b65d1627a7f75636f99", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98bcebb3a6a659ade6545bd0a3740346262cc31a3ca34b65d1627a7f75636f99", kill_on_drop: false }`
[INFO] [stdout] 98bcebb3a6a659ade6545bd0a3740346262cc31a3ca34b65d1627a7f75636f99
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9f52dd901631638ec83729a43d1f475b84e5412166817659739d1502c16c8d7b
[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" "9f52dd901631638ec83729a43d1f475b84e5412166817659739d1502c16c8d7b", kill_on_drop: false }`
[INFO] [stderr]    Compiling understanding-borrowing v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `y` is never read
[INFO] [stdout]  --> src/main.rs:3:13
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let mut y = x;
[INFO] [stdout]   |             ^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.96s
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "9f52dd901631638ec83729a43d1f475b84e5412166817659739d1502c16c8d7b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f52dd901631638ec83729a43d1f475b84e5412166817659739d1502c16c8d7b", kill_on_drop: false }`
[INFO] [stdout] 9f52dd901631638ec83729a43d1f475b84e5412166817659739d1502c16c8d7b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "test" "--frozen", 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] 5e6166f1b4163f3f87fc9d11700f92b78e268f1e2ff62be7a24d2a6d2e48f5d2
[INFO] running `Command { std: "docker" "start" "-a" "5e6166f1b4163f3f87fc9d11700f92b78e268f1e2ff62be7a24d2a6d2e48f5d2", kill_on_drop: false }`
[INFO] [stderr] warning: value assigned to `y` is never read
[INFO] [stderr]  --> src/main.rs:3:13
[INFO] [stderr]   |
[INFO] [stderr] 3 |     let mut y = x;
[INFO] [stderr]   |             ^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]   = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: `understanding-borrowing` (bin "understanding-borrowing" test) generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/understanding_borrowing-f0c6f8d87c6f8b6b)
[INFO] [stdout] running 0 tests
[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" "5e6166f1b4163f3f87fc9d11700f92b78e268f1e2ff62be7a24d2a6d2e48f5d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5e6166f1b4163f3f87fc9d11700f92b78e268f1e2ff62be7a24d2a6d2e48f5d2", kill_on_drop: false }`
[INFO] [stdout] 5e6166f1b4163f3f87fc9d11700f92b78e268f1e2ff62be7a24d2a6d2e48f5d2