[INFO] fetching crate rust_io 0.6.0...
[INFO] building rust_io-0.6.0 against try#4987e9d4227139400384ab59296ffee3b0fb1183 for pr-146237-2
[INFO] extracting crate rust_io 0.6.0 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate rust_io 0.6.0
[INFO] finished tweaking crates.io crate rust_io 0.6.0
[INFO] tweaked toml for crates.io crate rust_io 0.6.0 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate rust_io 0.6.0 on toolchain 4987e9d4227139400384ab59296ffee3b0fb1183
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 70 packages to latest compatible versions
[INFO] [stderr]       Adding rand v0.8.5 (available: v0.9.2)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a6bcbc28a2a58b31d0cde41d0fe0ab395cacd05e0d25c98259e1ca3021559080
[INFO] running `Command { std: "docker" "start" "-a" "a6bcbc28a2a58b31d0cde41d0fe0ab395cacd05e0d25c98259e1ca3021559080", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a6bcbc28a2a58b31d0cde41d0fe0ab395cacd05e0d25c98259e1ca3021559080", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a6bcbc28a2a58b31d0cde41d0fe0ab395cacd05e0d25c98259e1ca3021559080", kill_on_drop: false }`
[INFO] [stdout] a6bcbc28a2a58b31d0cde41d0fe0ab395cacd05e0d25c98259e1ca3021559080
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 202985bf4e8b6c09c372e299737147e4c85f260cc8db58a3f269e0600c3c291d
[INFO] running `Command { std: "docker" "start" "-a" "202985bf4e8b6c09c372e299737147e4c85f260cc8db58a3f269e0600c3c291d", kill_on_drop: false }`
[INFO] [stderr]    Compiling event-listener v5.4.1
[INFO] [stderr]    Compiling rustix v1.1.2
[INFO] [stderr]    Compiling linux-raw-sys v0.11.0
[INFO] [stderr]    Compiling async-io v2.6.0
[INFO] [stderr]    Compiling getrandom v0.2.16
[INFO] [stderr]    Compiling futures-macro v0.3.31
[INFO] [stderr]    Compiling log v0.4.28
[INFO] [stderr]    Compiling async-executor v1.13.3
[INFO] [stderr]    Compiling event-listener-strategy v0.5.4
[INFO] [stderr]    Compiling async-channel v2.5.0
[INFO] [stderr]    Compiling rand_core v0.6.4
[INFO] [stderr]    Compiling async-lock v3.4.1
[INFO] [stderr]    Compiling kv-log-macro v1.0.7
[INFO] [stderr]    Compiling blocking v1.6.2
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling futures-util v0.3.31
[INFO] [stderr]    Compiling rand v0.8.5
[INFO] [stderr]    Compiling futures-executor v0.3.31
[INFO] [stderr]    Compiling futures v0.3.31
[INFO] [stderr]    Compiling polling v3.11.0
[INFO] [stderr]    Compiling async-global-executor v2.4.1
[INFO] [stderr]    Compiling async-std v1.13.2
[INFO] [stderr]    Compiling rust_io v0.6.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `Rng` and `thread_rng`
[INFO] [stdout]  --> src/lib.rs:7:12
[INFO] [stdout]   |
[INFO] [stdout] 7 | use rand::{Rng, thread_rng};
[INFO] [stdout]   |            ^^^  ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 18.85s
[INFO] running `Command { std: "docker" "inspect" "202985bf4e8b6c09c372e299737147e4c85f260cc8db58a3f269e0600c3c291d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "202985bf4e8b6c09c372e299737147e4c85f260cc8db58a3f269e0600c3c291d", kill_on_drop: false }`
[INFO] [stdout] 202985bf4e8b6c09c372e299737147e4c85f260cc8db58a3f269e0600c3c291d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8486f99d8322e10a7e1f914c8416e6e3035e5b1171cab7719b43da2c570598af
[INFO] running `Command { std: "docker" "start" "-a" "8486f99d8322e10a7e1f914c8416e6e3035e5b1171cab7719b43da2c570598af", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_io v0.6.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `Rng` and `thread_rng`
[INFO] [stdout]  --> src/lib.rs:7:12
[INFO] [stdout]   |
[INFO] [stdout] 7 | use rand::{Rng, thread_rng};
[INFO] [stdout]   |            ^^^  ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> src/lib.rs:782:29
[INFO] [stdout]     |
[INFO] [stdout] 782 |                 .map_error(|t| String::from("Error B"));
[INFO] [stdout]     |                             ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> src/lib.rs:930:29
[INFO] [stdout]     |
[INFO] [stdout] 930 |                 .map_error(|t| String::from("Error B"))
[INFO] [stdout]     |                             ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 1.34s
[INFO] running `Command { std: "docker" "inspect" "8486f99d8322e10a7e1f914c8416e6e3035e5b1171cab7719b43da2c570598af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8486f99d8322e10a7e1f914c8416e6e3035e5b1171cab7719b43da2c570598af", kill_on_drop: false }`
[INFO] [stdout] 8486f99d8322e10a7e1f914c8416e6e3035e5b1171cab7719b43da2c570598af