[INFO] fetching crate grrrrrrs 0.1.0...
[INFO] checking grrrrrrs-0.1.0 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate grrrrrrs 0.1.0 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate grrrrrrs 0.1.0
[INFO] finished tweaking crates.io crate grrrrrrs 0.1.0
[INFO] tweaked toml for crates.io crate grrrrrrs 0.1.0 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate grrrrrrs 0.1.0 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 crates.io crate grrrrrrs 0.1.0 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] 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] fb389a4373bdc777c42faa914e87b1e6183ad08e34138f16b76389db00bca542
[INFO] running `Command { std: "docker" "start" "-a" "fb389a4373bdc777c42faa914e87b1e6183ad08e34138f16b76389db00bca542", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fb389a4373bdc777c42faa914e87b1e6183ad08e34138f16b76389db00bca542", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fb389a4373bdc777c42faa914e87b1e6183ad08e34138f16b76389db00bca542", kill_on_drop: false }`
[INFO] [stdout] fb389a4373bdc777c42faa914e87b1e6183ad08e34138f16b76389db00bca542
[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] 25315889f1b7c2d1acdd2f1fe6a84166d4e11bb5f219f6506ad15bb08c3cb460
[INFO] running `Command { std: "docker" "start" "-a" "25315889f1b7c2d1acdd2f1fe6a84166d4e11bb5f219f6506ad15bb08c3cb460", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.36
[INFO] [stderr]    Compiling syn v1.0.89
[INFO] [stderr]    Compiling libc v0.2.121
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling indexmap v1.8.0
[INFO] [stderr]     Checking textwrap v0.15.0
[INFO] [stderr]    Compiling quote v1.0.16
[INFO] [stderr]     Checking os_str_bytes v6.0.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling clap_derive v3.1.4
[INFO] [stderr]     Checking clap v3.1.6
[INFO] [stderr]     Checking grrrrrrs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `CustomError` is never constructed
[INFO] [stdout]  --> src/main.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | struct CustomError(String);
[INFO] [stdout]   |        ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     pattern: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `grrrrrrs` (bin "grrrrrrs" test) due to 1 previous error; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: struct `CustomError` is never constructed
[INFO] [stdout]  --> src/main.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | struct CustomError(String);
[INFO] [stdout]   |        ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     pattern: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `grrrrrrs` (bin "grrrrrrs") due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "25315889f1b7c2d1acdd2f1fe6a84166d4e11bb5f219f6506ad15bb08c3cb460", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "25315889f1b7c2d1acdd2f1fe6a84166d4e11bb5f219f6506ad15bb08c3cb460", kill_on_drop: false }`
[INFO] [stdout] 25315889f1b7c2d1acdd2f1fe6a84166d4e11bb5f219f6506ad15bb08c3cb460