[INFO] cloning repository https://github.com/thara/mandelbrot-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/thara/mandelbrot-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fthara%2Fmandelbrot-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fthara%2Fmandelbrot-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 86144d0cc5c9da1850cb0205d8b75c0ecb514a85
[INFO] checking thara/mandelbrot-rust against master#5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fthara%2Fmandelbrot-rust" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/thara/mandelbrot-rust on toolchain 5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/thara/mandelbrot-rust
[INFO] finished tweaking git repo https://github.com/thara/mandelbrot-rust
[INFO] tweaked toml for git repo https://github.com/thara/mandelbrot-rust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/thara/mandelbrot-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "fetch" "--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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bf43ebaeafec3b4a25f01cd0184f04454aaa23768a9068a71bdd872a80e5e354
[INFO] running `Command { std: "docker" "start" "-a" "bf43ebaeafec3b4a25f01cd0184f04454aaa23768a9068a71bdd872a80e5e354", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bf43ebaeafec3b4a25f01cd0184f04454aaa23768a9068a71bdd872a80e5e354", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bf43ebaeafec3b4a25f01cd0184f04454aaa23768a9068a71bdd872a80e5e354", kill_on_drop: false }`
[INFO] [stdout] bf43ebaeafec3b4a25f01cd0184f04454aaa23768a9068a71bdd872a80e5e354
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 35e2cfb1f82f04b71be330a1381e0ff7db8321960099056bb01e30a9fe98008e
[INFO] running `Command { std: "docker" "start" "-a" "35e2cfb1f82f04b71be330a1381e0ff7db8321960099056bb01e30a9fe98008e", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.47
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling arrayvec v0.4.10
[INFO] [stderr]    Compiling autocfg v0.1.2
[INFO] [stderr]    Compiling proc-macro2 v0.4.25
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]     Checking void v1.0.2
[INFO] [stderr]    Compiling num-bigint v0.2.2
[INFO] [stderr]    Compiling num-rational v0.2.1
[INFO] [stderr]     Checking lzw v0.10.0
[INFO] [stderr]    Compiling num-complex v0.2.1
[INFO] [stderr]     Checking color_quant v1.0.1
[INFO] [stderr]     Checking safe-transmute v0.10.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking crossbeam-utils v0.6.3
[INFO] [stderr]     Checking inflate v0.4.4
[INFO] [stderr]     Checking unreachable v1.0.0
[INFO] [stderr]     Checking smallvec v0.6.7
[INFO] [stderr]     Checking gif v0.10.1
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.4
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]     Checking png v0.14.0
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]     Checking crossbeam-epoch v0.3.1
[INFO] [stderr]     Checking crossbeam-epoch v0.7.0
[INFO] [stderr]    Compiling quote v0.6.10
[INFO] [stderr]    Compiling rand_pcg v0.1.1
[INFO] [stderr]    Compiling parking_lot_core v0.4.0
[INFO] [stderr]     Checking crossbeam-deque v0.2.0
[INFO] [stderr]    Compiling syn v0.15.26
[INFO] [stderr]     Checking rand_os v0.1.1
[INFO] [stderr]     Checking num_cpus v1.9.0
[INFO] [stderr]     Checking crossbeam-deque v0.6.3
[INFO] [stderr]     Checking rayon-core v1.4.1
[INFO] [stderr]     Checking rayon v1.0.3
[INFO] [stderr]     Checking num v0.2.0
[INFO] [stderr]     Checking parking_lot v0.7.1
[INFO] [stderr]     Checking crossbeam-channel v0.3.6
[INFO] [stderr]     Checking jpeg-decoder v0.1.15
[INFO] [stderr]     Checking crossbeam v0.6.0
[INFO] [stderr]    Compiling num-derive v0.2.3
[INFO] [stderr]     Checking tiff v0.2.1
[INFO] [stderr]     Checking image v0.21.0
[INFO] [stderr]     Checking mandelbrot v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:120:5
[INFO] [stdout]     |
[INFO] [stdout] 120 | /     encoder.encode(
[INFO] [stdout] 121 | |         &pixels,
[INFO] [stdout] 122 | |         bounds.0 as u32,
[INFO] [stdout] 123 | |         bounds.1 as u32,
[INFO] [stdout] 124 | |         ColorType::Gray(8),
[INFO] [stdout] 125 | |     );
[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: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:157:9
[INFO] [stdout]     |
[INFO] [stdout] 157 | /         crossbeam::scope(|spawner| {
[INFO] [stdout] 158 | |             for (i, band) in bands.into_iter().enumerate() {
[INFO] [stdout] 159 | |                 let top = rows_per_band * i;
[INFO] [stdout] 160 | |                 let height = band.len() / bounds.0;
[INFO] [stdout] ...   |
[INFO] [stdout] 167 | |             }
[INFO] [stdout] 168 | |         });
[INFO] [stdout]     | |___________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:120:5
[INFO] [stdout]     |
[INFO] [stdout] 120 | /     encoder.encode(
[INFO] [stdout] 121 | |         &pixels,
[INFO] [stdout] 122 | |         bounds.0 as u32,
[INFO] [stdout] 123 | |         bounds.1 as u32,
[INFO] [stdout] 124 | |         ColorType::Gray(8),
[INFO] [stdout] 125 | |     );
[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: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:157:9
[INFO] [stdout]     |
[INFO] [stdout] 157 | /         crossbeam::scope(|spawner| {
[INFO] [stdout] 158 | |             for (i, band) in bands.into_iter().enumerate() {
[INFO] [stdout] 159 | |                 let top = rows_per_band * i;
[INFO] [stdout] 160 | |                 let height = band.len() / bounds.0;
[INFO] [stdout] ...   |
[INFO] [stdout] 167 | |             }
[INFO] [stdout] 168 | |         });
[INFO] [stdout]     | |___________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.78s
[INFO] running `Command { std: "docker" "inspect" "35e2cfb1f82f04b71be330a1381e0ff7db8321960099056bb01e30a9fe98008e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "35e2cfb1f82f04b71be330a1381e0ff7db8321960099056bb01e30a9fe98008e", kill_on_drop: false }`
[INFO] [stdout] 35e2cfb1f82f04b71be330a1381e0ff7db8321960099056bb01e30a9fe98008e