[INFO] fetching crate cold 0.0.2...
[INFO] checking cold-0.0.2 against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] extracting crate cold 0.0.2 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate cold 0.0.2 on toolchain ceab6128fa48a616bfd3e3adf4bc80133b8ee223
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate cold 0.0.2
[INFO] finished tweaking crates.io crate cold 0.0.2
[INFO] tweaked toml for crates.io crate cold 0.0.2 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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 37 packages
[INFO] [stderr]       Adding mio v0.7.14 (latest: v0.8.11)
[INFO] [stderr]       Adding miow v0.3.7 (latest: v0.6.0)
[INFO] [stderr]       Adding ntapi v0.3.7 (latest: v0.4.1)
[INFO] [stderr]       Adding redox_syscall v0.1.57 (latest: v0.5.1)
[INFO] [stderr]       Adding thread-id v3.3.0 (latest: v4.2.1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 71346f8d3dc9886ada79ea2b910e3bf7810f05061d5d4539ca928642a3b164bc
[INFO] running `Command { std: "docker" "start" "-a" "71346f8d3dc9886ada79ea2b910e3bf7810f05061d5d4539ca928642a3b164bc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "71346f8d3dc9886ada79ea2b910e3bf7810f05061d5d4539ca928642a3b164bc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "71346f8d3dc9886ada79ea2b910e3bf7810f05061d5d4539ca928642a3b164bc", kill_on_drop: false }`
[INFO] [stdout] 71346f8d3dc9886ada79ea2b910e3bf7810f05061d5d4539ca928642a3b164bc
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b9e1460bc7ee6db030f6913d73b82671e7ba5697a5fe2287ff122a7a9992b367
[INFO] running `Command { std: "docker" "start" "-a" "b9e1460bc7ee6db030f6913d73b82671e7ba5697a5fe2287ff122a7a9992b367", kill_on_drop: false }`
[INFO] [stderr]     Checking crossbeam-epoch v0.9.18
[INFO] [stderr]     Checking crossbeam-queue v0.3.11
[INFO] [stderr]     Checking crossbeam-channel v0.5.12
[INFO] [stderr]     Checking mio v0.7.14
[INFO] [stderr]     Checking thread-id v3.3.0
[INFO] [stderr]    Compiling futures-macro v0.3.30
[INFO] [stderr]     Checking simple-logging v2.0.2
[INFO] [stderr]     Checking crossbeam-deque v0.8.5
[INFO] [stderr]     Checking crossbeam v0.8.4
[INFO] [stderr]     Checking futures-util v0.3.30
[INFO] [stderr]     Checking futures-executor v0.3.30
[INFO] [stderr]     Checking futures v0.3.30
[INFO] [stderr]     Checking cold v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/rt.rs:127:13
[INFO] [stdout]     |
[INFO] [stdout] 127 |         let mut ctx = ctxs.get_mut(&self.this).unwrap();
[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/rt.rs:127:13
[INFO] [stdout]     |
[INFO] [stdout] 127 |         let mut ctx = ctxs.get_mut(&self.this).unwrap();
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.89s
[INFO] running `Command { std: "docker" "inspect" "b9e1460bc7ee6db030f6913d73b82671e7ba5697a5fe2287ff122a7a9992b367", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b9e1460bc7ee6db030f6913d73b82671e7ba5697a5fe2287ff122a7a9992b367", kill_on_drop: false }`
[INFO] [stdout] b9e1460bc7ee6db030f6913d73b82671e7ba5697a5fe2287ff122a7a9992b367