[INFO] fetching crate jec-rccow 0.1.0...
[INFO] checking jec-rccow-0.1.0 against master#5ad98b4026d5172f27615b105658bc8bfd677be8 for pr-129422
[INFO] extracting crate jec-rccow 0.1.0 into /workspace/builds/worker-0-tc1/source
[INFO] validating manifest of crates.io crate jec-rccow 0.1.0 on toolchain 5ad98b4026d5172f27615b105658bc8bfd677be8
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+5ad98b4026d5172f27615b105658bc8bfd677be8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate jec-rccow 0.1.0
[INFO] finished tweaking crates.io crate jec-rccow 0.1.0
[INFO] tweaked toml for crates.io crate jec-rccow 0.1.0 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+5ad98b4026d5172f27615b105658bc8bfd677be8" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+5ad98b4026d5172f27615b105658bc8bfd677be8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "+5ad98b4026d5172f27615b105658bc8bfd677be8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7c8b3d58d45ab115e39d4a59c5f450739095e1675c151908a943257da68c2c71
[INFO] running `Command { std: "docker" "start" "-a" "7c8b3d58d45ab115e39d4a59c5f450739095e1675c151908a943257da68c2c71", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7c8b3d58d45ab115e39d4a59c5f450739095e1675c151908a943257da68c2c71", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7c8b3d58d45ab115e39d4a59c5f450739095e1675c151908a943257da68c2c71", kill_on_drop: false }`
[INFO] [stdout] 7c8b3d58d45ab115e39d4a59c5f450739095e1675c151908a943257da68c2c71
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "+5ad98b4026d5172f27615b105658bc8bfd677be8" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] bf1207aadaba775d67020f46210b3c24af39488db5ef532f8a26f97c5c50866c
[INFO] running `Command { std: "docker" "start" "-a" "bf1207aadaba775d67020f46210b3c24af39488db5ef532f8a26f97c5c50866c", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] [stderr]     Checking jec-rccow v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:73:13
[INFO] [stdout]    |
[INFO] [stdout] 73 |         let mut a = RcCow::new(5i32);
[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/lib.rs:77:13
[INFO] [stdout]    |
[INFO] [stdout] 77 |         let mut c = b.clone();
[INFO] [stdout]    |             ----^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.20s
[INFO] running `Command { std: "docker" "inspect" "bf1207aadaba775d67020f46210b3c24af39488db5ef532f8a26f97c5c50866c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bf1207aadaba775d67020f46210b3c24af39488db5ef532f8a26f97c5c50866c", kill_on_drop: false }`
[INFO] [stdout] bf1207aadaba775d67020f46210b3c24af39488db5ef532f8a26f97c5c50866c