[INFO] cloning repository https://github.com/cm-kazup0n/omc
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/cm-kazup0n/omc" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcm-kazup0n%2Fomc", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcm-kazup0n%2Fomc'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 464205d5204b5c69ef850c7a7ab13ad92d8937f2
[INFO] testing cm-kazup0n/omc against 1.54.0 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcm-kazup0n%2Fomc" "/workspace/builds/worker-30/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-30/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/cm-kazup0n/omc on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/cm-kazup0n/omc
[INFO] finished tweaking git repo https://github.com/cm-kazup0n/omc
[INFO] tweaked toml for git repo https://github.com/cm-kazup0n/omc written to /workspace/builds/worker-30/source/Cargo.toml
[INFO] crate git repo https://github.com/cm-kazup0n/omc already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-30/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-30/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" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a01194d9e68391cdbcc08b5ac55603a2385c311b8e24fc59057c9726bbf34c1c
[INFO] running `Command { std: "docker" "start" "-a" "a01194d9e68391cdbcc08b5ac55603a2385c311b8e24fc59057c9726bbf34c1c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a01194d9e68391cdbcc08b5ac55603a2385c311b8e24fc59057c9726bbf34c1c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a01194d9e68391cdbcc08b5ac55603a2385c311b8e24fc59057c9726bbf34c1c", kill_on_drop: false }`
[INFO] [stdout] a01194d9e68391cdbcc08b5ac55603a2385c311b8e24fc59057c9726bbf34c1c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-30/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-30/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c5113eab1361bedfbfe3c2c104373d0d3fe1fe304a71b9b54d98e3631664686c
[INFO] running `Command { std: "docker" "start" "-a" "c5113eab1361bedfbfe3c2c104373d0d3fe1fe304a71b9b54d98e3631664686c", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling libc v0.2.96
[INFO] [stderr]    Compiling syn v1.0.73
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling serde v1.0.126
[INFO] [stderr]    Compiling unicode-width v0.1.8
[INFO] [stderr]    Compiling ansi_term v0.11.0
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling dirs-sys v0.3.6
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling dirs v3.0.2
[INFO] [stderr]    Compiling toml v0.5.8
[INFO] [stderr]    Compiling opc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0277]: the `?` operator can only be used on `Option`s, not `Result`s, in a method that returns `Option`
[INFO] [stdout]   --> src/cache.rs:32:53
[INFO] [stdout]    |
[INFO] [stdout] 31 | /     pub fn restore_cache(&self) -> Option<TokenCache> {
[INFO] [stdout] 32 | |         let mut buf = Ok(BufReader::new(&self.file))?;
[INFO] [stdout]    | |                                                     ^ use `.ok()?` if you want to discard the `Result<Infallible, _>` error information
[INFO] [stdout] 33 | |         let mut line = String::new();
[INFO] [stdout] 34 | |         buf.read_line(&mut line).ok()?;
[INFO] [stdout] ...  |
[INFO] [stdout] 41 | |         };
[INFO] [stdout] 42 | |     }
[INFO] [stdout]    | |_____- this function returns an `Option`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `FromResidual<Result<Infallible, _>>` is not implemented for `std::option::Option<TokenCache>`
[INFO] [stdout]    = note: required by `from_residual`
[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 `opc`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "c5113eab1361bedfbfe3c2c104373d0d3fe1fe304a71b9b54d98e3631664686c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c5113eab1361bedfbfe3c2c104373d0d3fe1fe304a71b9b54d98e3631664686c", kill_on_drop: false }`
[INFO] [stdout] c5113eab1361bedfbfe3c2c104373d0d3fe1fe304a71b9b54d98e3631664686c
