[INFO] fetching crate buffer_io 1.0.3...
[INFO] checking buffer_io-1.0.3 against try#a7a572ce3edd6d476191fbfe92c9c1986e009b34 for pr-87190-3
[INFO] extracting crate buffer_io 1.0.3 into /workspace/builds/worker-58/source
[INFO] validating manifest of crates.io crate buffer_io 1.0.3 on toolchain a7a572ce3edd6d476191fbfe92c9c1986e009b34
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a7a572ce3edd6d476191fbfe92c9c1986e009b34" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate buffer_io 1.0.3
[INFO] finished tweaking crates.io crate buffer_io 1.0.3
[INFO] tweaked toml for crates.io crate buffer_io 1.0.3 written to /workspace/builds/worker-58/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a7a572ce3edd6d476191fbfe92c9c1986e009b34" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a7a572ce3edd6d476191fbfe92c9c1986e009b34" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-58/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-58/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" "+a7a572ce3edd6d476191fbfe92c9c1986e009b34" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e90e7acc1d53031efd60b65e00b5b0987e6587de6c29d631a587709916d49519
[INFO] running `Command { std: "docker" "start" "-a" "e90e7acc1d53031efd60b65e00b5b0987e6587de6c29d631a587709916d49519", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e90e7acc1d53031efd60b65e00b5b0987e6587de6c29d631a587709916d49519", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e90e7acc1d53031efd60b65e00b5b0987e6587de6c29d631a587709916d49519", kill_on_drop: false }`
[INFO] [stdout] e90e7acc1d53031efd60b65e00b5b0987e6587de6c29d631a587709916d49519
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-58/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-58/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" "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" "+a7a572ce3edd6d476191fbfe92c9c1986e009b34" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 06781940728f57239ab5a7e80b7cb755cf58e85a5a6c8046cd45921c8420b841
[INFO] running `Command { std: "docker" "start" "-a" "06781940728f57239ab5a7e80b7cb755cf58e85a5a6c8046cd45921c8420b841", kill_on_drop: false }`
[INFO] [stderr] Copying to /tmp/fixit
[INFO] [stderr] Running `cargo fix --edition`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.75
[INFO] [stderr]    Compiling thiserror-impl v1.0.26
[INFO] [stderr]     Checking thiserror v1.0.26
[INFO] [stderr]     Checking buffer_io v1.0.3 (/tmp/fixit)
[INFO] [stderr]    Migrating src/lib.rs from 2018 edition to 2021
[INFO] [stdout] warning: value assigned to `b` is never read
[INFO] [stdout]    --> src/lib.rs:211:21
[INFO] [stdout]     |
[INFO] [stdout] 211 |             let mut b: u8 = 0;
[INFO] [stdout]     |                     ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `b` is never read
[INFO] [stdout]    --> src/lib.rs:211:21
[INFO] [stdout]     |
[INFO] [stdout] 211 |             let mut b: u8 = 0;
[INFO] [stdout]     |                     ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 8.38s
[INFO] [stderr] Running `cargo check` to verify 2021
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking buffer_io v1.0.3 (/tmp/fixit)
[INFO] [stdout] warning: value assigned to `b` is never read
[INFO] [stdout]    --> src/lib.rs:211:21
[INFO] [stdout]     |
[INFO] [stdout] 211 |             let mut b: u8 = 0;
[INFO] [stdout]     |                     ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `b` is never read
[INFO] [stdout]    --> src/lib.rs:211:21
[INFO] [stdout]     |
[INFO] [stdout] 211 |             let mut b: u8 = 0;
[INFO] [stdout]     |                     ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.71s
[INFO] running `Command { std: "docker" "inspect" "06781940728f57239ab5a7e80b7cb755cf58e85a5a6c8046cd45921c8420b841", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "06781940728f57239ab5a7e80b7cb755cf58e85a5a6c8046cd45921c8420b841", kill_on_drop: false }`
[INFO] [stdout] 06781940728f57239ab5a7e80b7cb755cf58e85a5a6c8046cd45921c8420b841