[INFO] cloning repository https://github.com/AnthonyP4312/i3-alt-tab
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/AnthonyP4312/i3-alt-tab" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAnthonyP4312%2Fi3-alt-tab", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAnthonyP4312%2Fi3-alt-tab'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 64efd56944d26cce816fc0e4b7cefb9b5e201b0e
[INFO] checking AnthonyP4312/i3-alt-tab against try#b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f for pr-76104
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAnthonyP4312%2Fi3-alt-tab" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/AnthonyP4312/i3-alt-tab on toolchain b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/AnthonyP4312/i3-alt-tab
[INFO] finished tweaking git repo https://github.com/AnthonyP4312/i3-alt-tab
[INFO] tweaked toml for git repo https://github.com/AnthonyP4312/i3-alt-tab written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/AnthonyP4312/i3-alt-tab already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded quote v0.6.3
[INFO] [stderr]   Downloaded serde v1.0.66
[INFO] [stderr]   Downloaded syn v0.14.2
[INFO] [stderr]   Downloaded serde_derive v1.0.66
[INFO] [stderr]   Downloaded proc-macro2 v0.4.6
[INFO] [stderr]   Downloaded dtoa v0.4.2
[INFO] [stderr]   Downloaded itoa v0.4.1
[INFO] [stderr]   Downloaded serde_json v1.0.21
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1a0799775c11320ac928f59b311257f653d73efa42bdeec78e3dfa42c5b1ad39
[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" "1a0799775c11320ac928f59b311257f653d73efa42bdeec78e3dfa42c5b1ad39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1a0799775c11320ac928f59b311257f653d73efa42bdeec78e3dfa42c5b1ad39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1a0799775c11320ac928f59b311257f653d73efa42bdeec78e3dfa42c5b1ad39", kill_on_drop: false }`
[INFO] [stdout] 1a0799775c11320ac928f59b311257f653d73efa42bdeec78e3dfa42c5b1ad39
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ed52374b3cf9e39ad82046b8c235ab8f921c0a70c572aa69df849fbac988f59f
[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" "ed52374b3cf9e39ad82046b8c235ab8f921c0a70c572aa69df849fbac988f59f", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.66
[INFO] [stderr]     Checking dtoa v0.4.2
[INFO] [stderr]     Checking itoa v0.4.1
[INFO] [stderr]    Compiling proc-macro2 v0.4.6
[INFO] [stderr]    Compiling quote v0.6.3
[INFO] [stderr]    Compiling syn v0.14.2
[INFO] [stderr]    Compiling serde_derive v1.0.66
[INFO] [stderr]     Checking serde_json v1.0.21
[INFO] [stderr]     Checking alt_tabber v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `child_c`
[INFO] [stdout]   --> src/main.rs:85:13
[INFO] [stdout]    |
[INFO] [stdout] 85 |         let child_c = Node {
[INFO] [stdout]    |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_child_c`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `node_with_children`
[INFO] [stdout]   --> src/main.rs:89:13
[INFO] [stdout]    |
[INFO] [stdout] 89 |         let node_with_children = Node {
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_node_with_children`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `setup`
[INFO] [stdout]   --> src/main.rs:67:8
[INFO] [stdout]    |
[INFO] [stdout] 67 |     fn setup() {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:39:5
[INFO] [stdout]    |
[INFO] [stdout] 39 | /     Command::new("i3-msg")
[INFO] [stdout] 40 | |         .arg(format!("[con_id={}] focus", next.id))
[INFO] [stdout] 41 | |         .output();
[INFO] [stdout]    | |__________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:39:5
[INFO] [stdout]    |
[INFO] [stdout] 39 | /     Command::new("i3-msg")
[INFO] [stdout] 40 | |         .arg(format!("[con_id={}] focus", next.id))
[INFO] [stdout] 41 | |         .output();
[INFO] [stdout]    | |__________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 22.78s
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "ed52374b3cf9e39ad82046b8c235ab8f921c0a70c572aa69df849fbac988f59f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ed52374b3cf9e39ad82046b8c235ab8f921c0a70c572aa69df849fbac988f59f", kill_on_drop: false }`
[INFO] [stdout] ed52374b3cf9e39ad82046b8c235ab8f921c0a70c572aa69df849fbac988f59f