[INFO] fetching crate lmarkov 0.1.0...
[INFO] checking lmarkov-0.1.0 against 1.55.0 for beta-1.56-3
[INFO] extracting crate lmarkov 0.1.0 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate lmarkov 0.1.0 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate lmarkov 0.1.0
[INFO] finished tweaking crates.io crate lmarkov 0.1.0
[INFO] tweaked toml for crates.io crate lmarkov 0.1.0 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "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] 32fb4ac2f3d85ad0961031f1117cb3d01b2112ed018d0bfbc2a0d124f7ae066c
[INFO] running `Command { std: "docker" "start" "-a" "32fb4ac2f3d85ad0961031f1117cb3d01b2112ed018d0bfbc2a0d124f7ae066c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "32fb4ac2f3d85ad0961031f1117cb3d01b2112ed018d0bfbc2a0d124f7ae066c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32fb4ac2f3d85ad0961031f1117cb3d01b2112ed018d0bfbc2a0d124f7ae066c", kill_on_drop: false }`
[INFO] [stdout] 32fb4ac2f3d85ad0961031f1117cb3d01b2112ed018d0bfbc2a0d124f7ae066c
[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=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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "check" "--frozen" "--all" "--all-targets" "--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] 3cef5ba2646655cd36e04f18c2bf06052489a27aa00c4a7cedbc82f3acf6ee0b
[INFO] running `Command { std: "docker" "start" "-a" "3cef5ba2646655cd36e04f18c2bf06052489a27aa00c4a7cedbc82f3acf6ee0b", kill_on_drop: false }`
[INFO] [stderr]     Checking lmarkov v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0277]: `Option<String>` doesn't implement `std::fmt::Display`
[INFO] [stdout]   --> src/tests.rs:10:20
[INFO] [stdout]    |
[INFO] [stdout] 10 |     println!("{}", chain.generate());
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^ `Option<String>` cannot be formatted with the default formatter
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `std::fmt::Display` is not implemented for `Option<String>`
[INFO] [stdout]    = note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead
[INFO] [stdout]    = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lmarkov` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "3cef5ba2646655cd36e04f18c2bf06052489a27aa00c4a7cedbc82f3acf6ee0b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3cef5ba2646655cd36e04f18c2bf06052489a27aa00c4a7cedbc82f3acf6ee0b", kill_on_drop: false }`
[INFO] [stdout] 3cef5ba2646655cd36e04f18c2bf06052489a27aa00c4a7cedbc82f3acf6ee0b
