[INFO] cloning repository https://github.com/skies-unbroken/matrix
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/skies-unbroken/matrix" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fskies-unbroken%2Fmatrix", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fskies-unbroken%2Fmatrix'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e820095a0ccc1eadc7ee5de7ff829b551fe18536
[INFO] checking skies-unbroken/matrix against master#0d37dca25a51fb900a402c94c8818ad1c2789e30 for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fskies-unbroken%2Fmatrix" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/skies-unbroken/matrix on toolchain 0d37dca25a51fb900a402c94c8818ad1c2789e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/skies-unbroken/matrix
[INFO] finished tweaking git repo https://github.com/skies-unbroken/matrix
[INFO] tweaked toml for git repo https://github.com/skies-unbroken/matrix written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/skies-unbroken/matrix already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 954656149d40dca10698af363856ac7eea7d9800d336b013a0e4b2d5b32c5355
[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" "954656149d40dca10698af363856ac7eea7d9800d336b013a0e4b2d5b32c5355", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "954656149d40dca10698af363856ac7eea7d9800d336b013a0e4b2d5b32c5355", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "954656149d40dca10698af363856ac7eea7d9800d336b013a0e4b2d5b32c5355", kill_on_drop: false }`
[INFO] [stdout] 954656149d40dca10698af363856ac7eea7d9800d336b013a0e4b2d5b32c5355
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c1acdab3e60e4df738bbaff66a38a1c7cb271c5cf3312dfae61ce8967df00a18
[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" "c1acdab3e60e4df738bbaff66a38a1c7cb271c5cf3312dfae61ce8967df00a18", kill_on_drop: false }`
[INFO] [stderr]     Checking calc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> src/lib.rs:327:33
[INFO] [stdout]     |
[INFO] [stdout] 327 |         pub fn submatrix(&self, r1: usize, r2: usize) -> Matrix {
[INFO] [stdout]     |                                 ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]    --> src/lib.rs:327:44
[INFO] [stdout]     |
[INFO] [stdout] 327 |         pub fn submatrix(&self, r1: usize, r2: usize) -> Matrix {
[INFO] [stdout]     |                                            ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> src/lib.rs:327:33
[INFO] [stdout]     |
[INFO] [stdout] 327 |         pub fn submatrix(&self, r1: usize, r2: usize) -> Matrix {
[INFO] [stdout]     |                                 ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]    --> src/lib.rs:327:44
[INFO] [stdout]     |
[INFO] [stdout] 327 |         pub fn submatrix(&self, r1: usize, r2: usize) -> Matrix {
[INFO] [stdout]     |                                            ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.48s
[INFO] running `Command { std: "docker" "inspect" "c1acdab3e60e4df738bbaff66a38a1c7cb271c5cf3312dfae61ce8967df00a18", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c1acdab3e60e4df738bbaff66a38a1c7cb271c5cf3312dfae61ce8967df00a18", kill_on_drop: false }`
[INFO] [stdout] c1acdab3e60e4df738bbaff66a38a1c7cb271c5cf3312dfae61ce8967df00a18