[INFO] fetching crate regalloc 0.0.34...
[INFO] checking regalloc-0.0.34 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] extracting crate regalloc 0.0.34 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate regalloc 0.0.34 on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate regalloc 0.0.34
[INFO] finished tweaking crates.io crate regalloc 0.0.34
[INFO] tweaked toml for crates.io crate regalloc 0.0.34 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 10 packages to latest compatible versions
[INFO] [stderr]       Adding rustc-hash v1.1.0 (latest: v2.0.0)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f00883e41b27007657b819a720cb8ee9db3f5631e4df0d292be2d9c108693952
[INFO] running `Command { std: "docker" "start" "-a" "f00883e41b27007657b819a720cb8ee9db3f5631e4df0d292be2d9c108693952", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f00883e41b27007657b819a720cb8ee9db3f5631e4df0d292be2d9c108693952", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f00883e41b27007657b819a720cb8ee9db3f5631e4df0d292be2d9c108693952", kill_on_drop: false }`
[INFO] [stdout] f00883e41b27007657b819a720cb8ee9db3f5631e4df0d292be2d9c108693952
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ed73fcdd9c0bf882cbd1b6b99256279e55423d4e577faf0ebf6f8cda044ee862
[INFO] running `Command { std: "docker" "start" "-a" "ed73fcdd9c0bf882cbd1b6b99256279e55423d4e577faf0ebf6f8cda044ee862", kill_on_drop: false }`
[INFO] [stderr]     Checking regalloc v0.0.34 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/linear_scan/resolve_moves.rs:679:33
[INFO] [stdout]     |
[INFO] [stdout] 679 |                     if let Some(mut cycled) = find_cycled_move(stack, &mut stack_cur, blocking) {
[INFO] [stdout]     |                                 ----^^^^^^
[INFO] [stdout]     |                                 |
[INFO] [stdout]     |                                 help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/linear_scan/resolve_moves.rs:679:33
[INFO] [stdout]     |
[INFO] [stdout] 679 |                     if let Some(mut cycled) = find_cycled_move(stack, &mut stack_cur, blocking) {
[INFO] [stdout]     |                                 ----^^^^^^
[INFO] [stdout]     |                                 |
[INFO] [stdout]     |                                 help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `vreg` is never read
[INFO] [stdout]   --> src/snapshot.rs:20:13
[INFO] [stdout]    |
[INFO] [stdout] 20 |     Spill { vreg: Option<VirtualReg> },
[INFO] [stdout]    |     -----   ^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `IRInstKind` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `vreg` is never read
[INFO] [stdout]   --> src/snapshot.rs:21:14
[INFO] [stdout]    |
[INFO] [stdout] 21 |     Reload { vreg: Option<VirtualReg> },
[INFO] [stdout]    |     ------   ^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `IRInstKind` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `vreg` is never read
[INFO] [stdout]   --> src/snapshot.rs:22:12
[INFO] [stdout]    |
[INFO] [stdout] 22 |     Move { vreg: VirtualReg },
[INFO] [stdout]    |     ----   ^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `IRInstKind` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `vreg` is never read
[INFO] [stdout]   --> src/snapshot.rs:20:13
[INFO] [stdout]    |
[INFO] [stdout] 20 |     Spill { vreg: Option<VirtualReg> },
[INFO] [stdout]    |     -----   ^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `IRInstKind` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `vreg` is never read
[INFO] [stdout]   --> src/snapshot.rs:21:14
[INFO] [stdout]    |
[INFO] [stdout] 21 |     Reload { vreg: Option<VirtualReg> },
[INFO] [stdout]    |     ------   ^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `IRInstKind` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `vreg` is never read
[INFO] [stdout]   --> src/snapshot.rs:22:12
[INFO] [stdout]    |
[INFO] [stdout] 22 |     Move { vreg: VirtualReg },
[INFO] [stdout]    |     ----   ^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `IRInstKind` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.47s
[INFO] running `Command { std: "docker" "inspect" "ed73fcdd9c0bf882cbd1b6b99256279e55423d4e577faf0ebf6f8cda044ee862", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ed73fcdd9c0bf882cbd1b6b99256279e55423d4e577faf0ebf6f8cda044ee862", kill_on_drop: false }`
[INFO] [stdout] ed73fcdd9c0bf882cbd1b6b99256279e55423d4e577faf0ebf6f8cda044ee862