[INFO] updating cached repository thara/mandelbrot-rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/thara/mandelbrot-rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/thara/mandelbrot-rust" "work/ex/pr-61874/sources/master#9f06855064ed06a50c496577b21ca50f92a2e67d/gh/thara/mandelbrot-rust"`
[INFO] [stderr] Cloning into 'work/ex/pr-61874/sources/master#9f06855064ed06a50c496577b21ca50f92a2e67d/gh/thara/mandelbrot-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/thara/mandelbrot-rust" "work/ex/pr-61874/sources/try#d3301713b54af69ca9de941a8c6b0d8287dbd6df/gh/thara/mandelbrot-rust"`
[INFO] [stderr] Cloning into 'work/ex/pr-61874/sources/try#d3301713b54af69ca9de941a8c6b0d8287dbd6df/gh/thara/mandelbrot-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 86144d0cc5c9da1850cb0205d8b75c0ecb514a85
[INFO] sha for GitHub repo thara/mandelbrot-rust: 86144d0cc5c9da1850cb0205d8b75c0ecb514a85
[INFO] validating manifest of thara/mandelbrot-rust on toolchain master#9f06855064ed06a50c496577b21ca50f92a2e67d
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+9f06855064ed06a50c496577b21ca50f92a2e67d-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of thara/mandelbrot-rust on toolchain try#d3301713b54af69ca9de941a8c6b0d8287dbd6df
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+d3301713b54af69ca9de941a8c6b0d8287dbd6df-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing thara/mandelbrot-rust
[INFO] finished frobbing thara/mandelbrot-rust
[INFO] frobbed toml for thara/mandelbrot-rust written to work/ex/pr-61874/sources/master#9f06855064ed06a50c496577b21ca50f92a2e67d/gh/thara/mandelbrot-rust/Cargo.toml
[INFO] started frobbing thara/mandelbrot-rust
[INFO] finished frobbing thara/mandelbrot-rust
[INFO] frobbed toml for thara/mandelbrot-rust written to work/ex/pr-61874/sources/try#d3301713b54af69ca9de941a8c6b0d8287dbd6df/gh/thara/mandelbrot-rust/Cargo.toml
[INFO] crate thara/mandelbrot-rust already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+9f06855064ed06a50c496577b21ca50f92a2e67d-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+d3301713b54af69ca9de941a8c6b0d8287dbd6df-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache lock
[INFO] checking thara/mandelbrot-rust against try#d3301713b54af69ca9de941a8c6b0d8287dbd6df for pr-61874
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-61874/worker-7/try#d3301713b54af69ca9de941a8c6b0d8287dbd6df:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-61874/sources/try#d3301713b54af69ca9de941a8c6b0d8287dbd6df/gh/thara/mandelbrot-rust:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+d3301713b54af69ca9de941a8c6b0d8287dbd6df-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 71f1a22ce718b9f9c9297155d0899c3ea9c55d84ba3d1d90abe91eece001a3e3
[INFO] running `"docker" "start" "-a" "71f1a22ce718b9f9c9297155d0899c3ea9c55d84ba3d1d90abe91eece001a3e3"`
[INFO] [stderr]    Compiling num-complex v0.2.1
[INFO] [stderr]     Checking safe-transmute v0.10.1
[INFO] [stderr]     Checking crossbeam-epoch v0.3.1
[INFO] [stderr]    Compiling syn v0.15.26
[INFO] [stderr]     Checking num-bigint v0.2.2
[INFO] [stderr]     Checking png v0.14.0
[INFO] [stderr]     Checking crossbeam v0.6.0
[INFO] [stderr]     Checking crossbeam-deque v0.2.0
[INFO] [stderr]     Checking rayon-core v1.4.1
[INFO] [stderr]     Checking rayon v1.0.3
[INFO] [stderr]     Checking num-rational v0.2.1
[INFO] [stderr]     Checking num v0.2.0
[INFO] [stderr]    Compiling num-derive v0.2.3
[INFO] [stderr]     Checking jpeg-decoder v0.1.15
[INFO] [stderr]     Checking tiff v0.2.1
[INFO] [stderr]     Checking image v0.21.0
[INFO] [stderr]     Checking mandelbrot v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:120:5
[INFO] [stderr]     |
[INFO] [stderr] 120 | /     encoder.encode(
[INFO] [stderr] 121 | |         &pixels,
[INFO] [stderr] 122 | |         bounds.0 as u32,
[INFO] [stderr] 123 | |         bounds.1 as u32,
[INFO] [stderr] 124 | |         ColorType::Gray(8),
[INFO] [stderr] 125 | |     );
[INFO] [stderr]     | |______^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_must_use)] on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:157:9
[INFO] [stderr]     |
[INFO] [stderr] 157 | /         crossbeam::scope(|spawner| {
[INFO] [stderr] 158 | |             for (i, band) in bands.into_iter().enumerate() {
[INFO] [stderr] 159 | |                 let top = rows_per_band * i;
[INFO] [stderr] 160 | |                 let height = band.len() / bounds.0;
[INFO] [stderr] ...   |
[INFO] [stderr] 167 | |             }
[INFO] [stderr] 168 | |         });
[INFO] [stderr]     | |___________^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:120:5
[INFO] [stderr]     |
[INFO] [stderr] 120 | /     encoder.encode(
[INFO] [stderr] 121 | |         &pixels,
[INFO] [stderr] 122 | |         bounds.0 as u32,
[INFO] [stderr] 123 | |         bounds.1 as u32,
[INFO] [stderr] 124 | |         ColorType::Gray(8),
[INFO] [stderr] 125 | |     );
[INFO] [stderr]     | |______^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_must_use)] on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:157:9
[INFO] [stderr]     |
[INFO] [stderr] 157 | /         crossbeam::scope(|spawner| {
[INFO] [stderr] 158 | |             for (i, band) in bands.into_iter().enumerate() {
[INFO] [stderr] 159 | |                 let top = rows_per_band * i;
[INFO] [stderr] 160 | |                 let height = band.len() / bounds.0;
[INFO] [stderr] ...   |
[INFO] [stderr] 167 | |             }
[INFO] [stderr] 168 | |         });
[INFO] [stderr]     | |___________^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 26.18s
[INFO] running `"docker" "inspect" "71f1a22ce718b9f9c9297155d0899c3ea9c55d84ba3d1d90abe91eece001a3e3"`
[INFO] running `"docker" "rm" "-f" "71f1a22ce718b9f9c9297155d0899c3ea9c55d84ba3d1d90abe91eece001a3e3"`
[INFO] [stdout] 71f1a22ce718b9f9c9297155d0899c3ea9c55d84ba3d1d90abe91eece001a3e3