[INFO] cloning repository https://github.com/PrVrSs/py-binary-tree
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/PrVrSs/py-binary-tree" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPrVrSs%2Fpy-binary-tree", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPrVrSs%2Fpy-binary-tree'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a111c976d9fdf9ad9db761d34a5448f6b4c09071
[INFO] checking PrVrSs/py-binary-tree against try#3e22d1f9053c0fc87629b3c6d5d9567856368e5d for pr-78714
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPrVrSs%2Fpy-binary-tree" "/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/PrVrSs/py-binary-tree on toolchain 3e22d1f9053c0fc87629b3c6d5d9567856368e5d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/PrVrSs/py-binary-tree
[INFO] finished tweaking git repo https://github.com/PrVrSs/py-binary-tree
[INFO] tweaked toml for git repo https://github.com/PrVrSs/py-binary-tree written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/PrVrSs/py-binary-tree already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded pyo3-derive-backend v0.9.2
[INFO] [stderr]   Downloaded pyo3cls v0.9.2
[INFO] [stderr]   Downloaded pyo3 v0.9.2
[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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "metadata" "--no-deps" "--format-version=1", 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] a3429cf4026d88251b81dce01e6a1d23a246a144fd47a9375bde4ef9b953ed5b
[INFO] running `Command { std: "docker" "start" "-a" "a3429cf4026d88251b81dce01e6a1d23a246a144fd47a9375bde4ef9b953ed5b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a3429cf4026d88251b81dce01e6a1d23a246a144fd47a9375bde4ef9b953ed5b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a3429cf4026d88251b81dce01e6a1d23a246a144fd47a9375bde4ef9b953ed5b", kill_on_drop: false }`
[INFO] [stdout] a3429cf4026d88251b81dce01e6a1d23a246a144fd47a9375bde4ef9b953ed5b
[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=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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 20fd493184a824b9f700b2846e5eea4ffb575d37b3990f0d639e8942f8833ff5
[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" "20fd493184a824b9f700b2846e5eea4ffb575d37b3990f0d639e8942f8833ff5", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling serde v1.0.106
[INFO] [stderr]    Compiling proc-macro-hack v0.5.15
[INFO] [stderr]    Compiling itoa v0.4.5
[INFO] [stderr]    Compiling regex-syntax v0.6.17
[INFO] [stderr]    Compiling unindent v0.1.5
[INFO] [stderr]    Compiling inventory v0.1.6
[INFO] [stderr]     Checking lock_api v0.3.4
[INFO] [stderr]    Compiling ryu v1.0.3
[INFO] [stderr]     Checking parking_lot_core v0.7.1
[INFO] [stderr]     Checking parking_lot v0.10.2
[INFO] [stderr]    Compiling regex v1.3.6
[INFO] [stderr]    Compiling pyo3-derive-backend v0.9.2
[INFO] [stderr]    Compiling serde_derive v1.0.106
[INFO] [stderr]    Compiling inventory-impl v0.1.6
[INFO] [stderr]    Compiling paste-impl v0.1.10
[INFO] [stderr]    Compiling ghost v0.1.1
[INFO] [stderr]    Compiling indoc-impl v0.3.5
[INFO] [stderr]    Compiling ctor v0.1.13
[INFO] [stderr]    Compiling pyo3cls v0.9.2
[INFO] [stderr]     Checking paste v0.1.10
[INFO] [stderr]     Checking indoc v0.3.5
[INFO] [stderr]    Compiling serde_json v1.0.51
[INFO] [stderr]    Compiling pyo3 v0.9.2
[INFO] [stderr]     Checking py-binary-tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/tree.rs:136:17
[INFO] [stdout]     |
[INFO] [stdout] 136 |                 mem::replace(target_node, Some(Box::new(new_node)));
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/tree.rs:136:17
[INFO] [stdout]     |
[INFO] [stdout] 136 |                 mem::replace(target_node, Some(Box::new(new_node)));
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 01s
[INFO] running `Command { std: "docker" "inspect" "20fd493184a824b9f700b2846e5eea4ffb575d37b3990f0d639e8942f8833ff5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "20fd493184a824b9f700b2846e5eea4ffb575d37b3990f0d639e8942f8833ff5", kill_on_drop: false }`
[INFO] [stdout] 20fd493184a824b9f700b2846e5eea4ffb575d37b3990f0d639e8942f8833ff5