[INFO] fetching crate liftoff 0.1.1...
[INFO] checking liftoff-0.1.1 against beta for pr-78714
[INFO] extracting crate liftoff 0.1.1 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate liftoff 0.1.1 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate liftoff 0.1.1
[INFO] finished tweaking crates.io crate liftoff 0.1.1
[INFO] tweaked toml for crates.io crate liftoff 0.1.1 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded leg v0.1.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "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] 95a7d17a92613fce8ce8698ed0c23a8a0dd0aa0bdb900e523ce0bf9238b02fba
[INFO] running `Command { std: "docker" "start" "-a" "95a7d17a92613fce8ce8698ed0c23a8a0dd0aa0bdb900e523ce0bf9238b02fba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "95a7d17a92613fce8ce8698ed0c23a8a0dd0aa0bdb900e523ce0bf9238b02fba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "95a7d17a92613fce8ce8698ed0c23a8a0dd0aa0bdb900e523ce0bf9238b02fba", kill_on_drop: false }`
[INFO] [stdout] 95a7d17a92613fce8ce8698ed0c23a8a0dd0aa0bdb900e523ce0bf9238b02fba
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--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] 709107e4091c207997ae7384762f1ac0fe194141b28263d9fb048abd0163e834
[INFO] running `Command { std: "docker" "start" "-a" "709107e4091c207997ae7384762f1ac0fe194141b28263d9fb048abd0163e834", kill_on_drop: false }`
[INFO] [stderr]    Compiling libz-sys v1.1.2
[INFO] [stderr]    Compiling curl-sys v0.4.38+curl-7.73.0
[INFO] [stderr]    Compiling libssh2-sys v0.2.19
[INFO] [stderr]    Compiling libgit2-sys v0.7.11
[INFO] [stderr]     Checking leg v0.1.3
[INFO] [stderr]     Checking sane v0.2.1
[INFO] [stderr]     Checking git2 v0.8.0
[INFO] [stderr]     Checking liftoff v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/config.rs:304:13
[INFO] [stdout]     |
[INFO] [stdout] 304 |         let mut file;
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/config.rs:304:13
[INFO] [stdout]     |
[INFO] [stdout] 304 |         let mut file;
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/variables.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     mem::replace(input, Cow::Owned(input.replace(from, to.as_ref())));
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/variables.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     mem::replace(input, Cow::Owned(input.replace(from, to.as_ref())));
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 56.01s
[INFO] running `Command { std: "docker" "inspect" "709107e4091c207997ae7384762f1ac0fe194141b28263d9fb048abd0163e834", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "709107e4091c207997ae7384762f1ac0fe194141b28263d9fb048abd0163e834", kill_on_drop: false }`
[INFO] [stdout] 709107e4091c207997ae7384762f1ac0fe194141b28263d9fb048abd0163e834