[INFO] cloning repository https://github.com/davesabra/Mandelbrot-set-graphic-by-Rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/davesabra/Mandelbrot-set-graphic-by-Rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavesabra%2FMandelbrot-set-graphic-by-Rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavesabra%2FMandelbrot-set-graphic-by-Rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9e15b2cc76e694ca8171bc28e720e432b455c4a5
[INFO] testing davesabra/Mandelbrot-set-graphic-by-Rust against beta-2021-01-01 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavesabra%2FMandelbrot-set-graphic-by-Rust" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/davesabra/Mandelbrot-set-graphic-by-Rust on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/davesabra/Mandelbrot-set-graphic-by-Rust
[INFO] finished tweaking git repo https://github.com/davesabra/Mandelbrot-set-graphic-by-Rust
[INFO] tweaked toml for git repo https://github.com/davesabra/Mandelbrot-set-graphic-by-Rust written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/davesabra/Mandelbrot-set-graphic-by-Rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded crossbeam v0.7.1
[INFO] [stderr]   Downloaded proc-macro2 v0.4.28
[INFO] [stderr]   Downloaded image v0.21.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "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] 55f82dc386c9f3d05c6ad11e6fc1133c92e077d5238a5af612100a05b4994d13
[INFO] running `Command { std: "docker" "start" "-a" "55f82dc386c9f3d05c6ad11e6fc1133c92e077d5238a5af612100a05b4994d13", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "55f82dc386c9f3d05c6ad11e6fc1133c92e077d5238a5af612100a05b4994d13", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "55f82dc386c9f3d05c6ad11e6fc1133c92e077d5238a5af612100a05b4994d13", kill_on_drop: false }`
[INFO] [stdout] 55f82dc386c9f3d05c6ad11e6fc1133c92e077d5238a5af612100a05b4994d13
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--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] 9ea5accba4215c3f3817a337add935a89ffb0b0ea5274f85a3cebf0e95fe0fe6
[INFO] running `Command { std: "docker" "start" "-a" "9ea5accba4215c3f3817a337add935a89ffb0b0ea5274f85a3cebf0e95fe0fe6", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.6
[INFO] [stderr]    Compiling num-integer v0.1.39
[INFO] [stderr]    Compiling libc v0.2.53
[INFO] [stderr]    Compiling proc-macro2 v0.4.28
[INFO] [stderr]    Compiling rayon-core v1.4.1
[INFO] [stderr]    Compiling num-iter v0.1.37
[INFO] [stderr]    Compiling syn v0.15.33
[INFO] [stderr]    Compiling num-bigint v0.2.2
[INFO] [stderr]    Compiling adler32 v1.0.3
[INFO] [stderr]    Compiling num-rational v0.2.1
[INFO] [stderr]    Compiling rayon v1.0.3
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]    Compiling either v1.5.2
[INFO] [stderr]    Compiling num-complex v0.2.1
[INFO] [stderr]    Compiling crossbeam-utils v0.2.2
[INFO] [stderr]    Compiling inflate v0.4.5
[INFO] [stderr]    Compiling gif v0.10.1
[INFO] [stderr]    Compiling crossbeam-epoch v0.3.1
[INFO] [stderr]    Compiling deflate v0.7.19
[INFO] [stderr]    Compiling crossbeam v0.7.1
[INFO] [stderr]    Compiling crossbeam-deque v0.2.0
[INFO] [stderr]    Compiling num_cpus v1.10.0
[INFO] [stderr]    Compiling quote v0.6.12
[INFO] [stderr]    Compiling png v0.14.1
[INFO] [stderr]    Compiling jpeg-decoder v0.1.15
[INFO] [stderr]    Compiling num v0.2.0
[INFO] [stderr]    Compiling tiff v0.2.2
[INFO] [stderr]    Compiling image v0.21.1
[INFO] [stderr]    Compiling mandelbrot v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0599]: no method named `write_fmt` found for struct `Stderr` in the current scope
[INFO] [stdout]     --> src/main.rs:140:9
[INFO] [stdout]      |
[INFO] [stdout] 140  | /         writeln!(
[INFO] [stdout] 141  | |             std::io::stderr(),
[INFO] [stdout] 142  | |             "Usage:    mandelbrot FILE    PIXELS UPPERLEFT LOWERRIGHT"
[INFO] [stdout] 143  | |         )
[INFO] [stdout]      | |_________^ method not found in `Stderr`
[INFO] [stdout]      |
[INFO] [stdout]      = help: items from traits can only be used if the trait is in scope
[INFO] [stdout]      = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: the following trait is implemented but not in scope; perhaps add a `use` for it:
[INFO] [stdout]      |
[INFO] [stdout] 2    | use std::io::Write;
[INFO] [stdout]      |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `write_fmt` found for struct `Stderr` in the current scope
[INFO] [stdout]     --> src/main.rs:145:9
[INFO] [stdout]      |
[INFO] [stdout] 145  | /         writeln!(
[INFO] [stdout] 146  | |             std::io::stderr(),
[INFO] [stdout] 147  | |             "Example: {} mandel.png    1000x750 -1.20,0.35    -1,0.20",
[INFO] [stdout] 148  | |             args[0]
[INFO] [stdout] 149  | |         )
[INFO] [stdout]      | |_________^ method not found in `Stderr`
[INFO] [stdout]      |
[INFO] [stdout]      = help: items from traits can only be used if the trait is in scope
[INFO] [stdout]      = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: the following trait is implemented but not in scope; perhaps add a `use` for it:
[INFO] [stdout]      |
[INFO] [stdout] 2    | use std::io::Write;
[INFO] [stdout]      |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0599`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mandelbrot`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "9ea5accba4215c3f3817a337add935a89ffb0b0ea5274f85a3cebf0e95fe0fe6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9ea5accba4215c3f3817a337add935a89ffb0b0ea5274f85a3cebf0e95fe0fe6", kill_on_drop: false }`
[INFO] [stdout] 9ea5accba4215c3f3817a337add935a89ffb0b0ea5274f85a3cebf0e95fe0fe6