[INFO] cloning repository https://github.com/qinyuhang/rust_coreutil
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/qinyuhang/rust_coreutil" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqinyuhang%2Frust_coreutil", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqinyuhang%2Frust_coreutil'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b4519ea4bf79c8cf6c6e3876c38e77b24a1d68e0
[INFO] checking qinyuhang/rust_coreutil against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqinyuhang%2Frust_coreutil" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/qinyuhang/rust_coreutil
[INFO] finished tweaking git repo https://github.com/qinyuhang/rust_coreutil
[INFO] tweaked toml for git repo https://github.com/qinyuhang/rust_coreutil written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/qinyuhang/rust_coreutil on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/qinyuhang/rust_coreutil already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "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-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ea2ba2030f94a87e89e05fd77fb5f1555791d5eef86b2eda1d23429e37cb7b88
[INFO] running `Command { std: "docker" "start" "-a" "ea2ba2030f94a87e89e05fd77fb5f1555791d5eef86b2eda1d23429e37cb7b88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ea2ba2030f94a87e89e05fd77fb5f1555791d5eef86b2eda1d23429e37cb7b88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ea2ba2030f94a87e89e05fd77fb5f1555791d5eef86b2eda1d23429e37cb7b88", kill_on_drop: false }`
[INFO] [stdout] ea2ba2030f94a87e89e05fd77fb5f1555791d5eef86b2eda1d23429e37cb7b88
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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 -Dunmustuse_in_always_ok" "-e" "RUSTDOCFLAGS=--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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7d4e6b461385207fdb114d8b7e4cca330af0285afae8bb447d6802c19d356384
[INFO] running `Command { std: "docker" "start" "-a" "7d4e6b461385207fdb114d8b7e4cca330af0285afae8bb447d6802c19d356384", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.36
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.89
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]    Compiling libc v0.2.121
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling serde_derive v1.0.136
[INFO] [stderr]    Compiling indexmap v1.8.0
[INFO] [stderr]    Compiling serde v1.0.136
[INFO] [stderr]    Compiling doc-comment v0.3.3
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]     Checking predicates-core v1.0.3
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]     Checking termtree v0.2.4
[INFO] [stderr]     Checking difflib v0.4.0
[INFO] [stderr]     Checking itertools v0.10.3
[INFO] [stderr]    Compiling serde_json v1.0.79
[INFO] [stderr]    Compiling heck v0.4.0
[INFO] [stderr]     Checking regex-automata v0.1.10
[INFO] [stderr]     Checking hashbrown v0.11.2
[INFO] [stderr]    Compiling quote v1.0.16
[INFO] [stderr]     Checking os_str_bytes v6.0.0
[INFO] [stderr]     Checking predicates-tree v1.0.5
[INFO] [stderr]     Checking bstr v0.2.17
[INFO] [stderr]     Checking textwrap v0.15.0
[INFO] [stderr]     Checking termcolor v1.1.3
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking wait-timeout v0.2.0
[INFO] [stderr]     Checking itoa v1.0.1
[INFO] [stderr]     Checking strsim v0.10.0
[INFO] [stderr]     Checking ryu v1.0.9
[INFO] [stderr]     Checking predicates v2.1.1
[INFO] [stderr]     Checking assert_cmd v2.0.4
[INFO] [stderr]    Compiling clap_derive v3.1.4
[INFO] [stderr]     Checking clap v3.1.6
[INFO] [stderr]     Checking rust_coreutil v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/bin/uniq.rs:60:5
[INFO] [stdout]    |
[INFO] [stdout] 60 | /     /// input file
[INFO] [stdout] 61 | |     #[clap(default_value = "-")]
[INFO] [stdout] 62 | |     input_file: String,
[INFO] [stdout]    | |______________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/bin/uniq.rs:64:5
[INFO] [stdout]    |
[INFO] [stdout] 64 | /     /// the output file
[INFO] [stdout] 65 | |     /// if not exist, create one
[INFO] [stdout] 66 | |     #[clap(default_value = "-")]
[INFO] [stdout] 67 | |     output_file: String,
[INFO] [stdout]    | |_______________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/uniq.rs:72:9
[INFO] [stdout]    |
[INFO] [stdout] 72 |         output.write(format!("{:>4} {}", line_data.1, line_data.0).as_bytes());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 72 |         let _ = output.write(format!("{:>4} {}", line_data.1, line_data.0).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/uniq.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |             output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 75 |             let _ = output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/uniq.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |         output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 78 |         let _ = output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust_coreutil` (bin "uniq" test) due to 2 previous errors; 3 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/bin/uniq.rs:60:5
[INFO] [stdout]    |
[INFO] [stdout] 60 | /     /// input file
[INFO] [stdout] 61 | |     #[clap(default_value = "-")]
[INFO] [stdout] 62 | |     input_file: String,
[INFO] [stdout]    | |______________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/bin/uniq.rs:64:5
[INFO] [stdout]    |
[INFO] [stdout] 64 | /     /// the output file
[INFO] [stdout] 65 | |     /// if not exist, create one
[INFO] [stdout] 66 | |     #[clap(default_value = "-")]
[INFO] [stdout] 67 | |     output_file: String,
[INFO] [stdout]    | |_______________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/uniq.rs:72:9
[INFO] [stdout]    |
[INFO] [stdout] 72 |         output.write(format!("{:>4} {}", line_data.1, line_data.0).as_bytes());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 72 |         let _ = output.write(format!("{:>4} {}", line_data.1, line_data.0).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/uniq.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |             output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 75 |             let _ = output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/uniq.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |         output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 78 |         let _ = output.write(format!("{}", line_data.0).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust_coreutil` (bin "uniq") due to 2 previous errors; 3 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "7d4e6b461385207fdb114d8b7e4cca330af0285afae8bb447d6802c19d356384", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d4e6b461385207fdb114d8b7e4cca330af0285afae8bb447d6802c19d356384", kill_on_drop: false }`
[INFO] [stdout] 7d4e6b461385207fdb114d8b7e4cca330af0285afae8bb447d6802c19d356384
