[INFO] cloning repository https://github.com/mikaelmello/tac
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mikaelmello/tac" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmikaelmello%2Ftac", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmikaelmello%2Ftac'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b006b35671369ea43ff89313e3854b9ff1cd8beb
[INFO] checking mikaelmello/tac 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%2Fmikaelmello%2Ftac" "/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/mikaelmello/tac
[INFO] finished tweaking git repo https://github.com/mikaelmello/tac
[INFO] tweaked toml for git repo https://github.com/mikaelmello/tac written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/mikaelmello/tac 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/mikaelmello/tac 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] 00cffc46541e98a5d48f153dc05d001aaafa461c65e27081069095c2fd98ef03
[INFO] running `Command { std: "docker" "start" "-a" "00cffc46541e98a5d48f153dc05d001aaafa461c65e27081069095c2fd98ef03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "00cffc46541e98a5d48f153dc05d001aaafa461c65e27081069095c2fd98ef03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "00cffc46541e98a5d48f153dc05d001aaafa461c65e27081069095c2fd98ef03", kill_on_drop: false }`
[INFO] [stdout] 00cffc46541e98a5d48f153dc05d001aaafa461c65e27081069095c2fd98ef03
[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] 08f7b2f41f19e3c7b0fef27f8060334da1e2235a67f0a2588a411af6296ec9d6
[INFO] running `Command { std: "docker" "start" "-a" "08f7b2f41f19e3c7b0fef27f8060334da1e2235a67f0a2588a411af6296ec9d6", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.101
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]    Compiling indexmap v1.7.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]     Checking nibble_vec v0.1.0
[INFO] [stderr]     Checking textwrap v0.14.2
[INFO] [stderr]     Checking os_str_bytes v3.1.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking utf8parse v0.2.0
[INFO] [stderr]     Checking radix_trie v0.2.1
[INFO] [stderr]     Checking dirs-sys-next v0.1.2
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking nix v0.22.1
[INFO] [stderr]     Checking fd-lock v3.0.0
[INFO] [stderr]     Checking dirs-next v2.0.0
[INFO] [stderr]    Compiling clap_derive v3.0.0-beta.4
[INFO] [stderr]     Checking rustyline v9.0.0
[INFO] [stderr]     Checking clap v3.0.0-beta.4
[INFO] [stderr]     Checking tac v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: method `disassemble` is never used
[INFO] [stdout]   --> src/disassembler.rs:12:12
[INFO] [stdout]    |
[INFO] [stdout]  7 | impl<'a> Disassembler<'a> {
[INFO] [stdout]    | ------------------------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 12 |     pub fn disassemble(self, name: &str) {
[INFO] [stdout]    |            ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tac` (bin "tac") due to 1 previous error; 1 warning emitted
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]  --> src/opts.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | /     /// File path for script to be run
[INFO] [stdout] 8 | |     pub script: Option<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] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: method `disassemble` is never used
[INFO] [stdout]   --> src/disassembler.rs:12:12
[INFO] [stdout]    |
[INFO] [stdout]  7 | impl<'a> Disassembler<'a> {
[INFO] [stdout]    | ------------------------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 12 |     pub fn disassemble(self, name: &str) {
[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<String, Infallible>
[INFO] [stdout]  --> src/opts.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | /     /// File path for script to be run
[INFO] [stdout] 8 | |     pub script: Option<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 `tac` (bin "tac" test) due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "08f7b2f41f19e3c7b0fef27f8060334da1e2235a67f0a2588a411af6296ec9d6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "08f7b2f41f19e3c7b0fef27f8060334da1e2235a67f0a2588a411af6296ec9d6", kill_on_drop: false }`
[INFO] [stdout] 08f7b2f41f19e3c7b0fef27f8060334da1e2235a67f0a2588a411af6296ec9d6