[INFO] cloning repository https://github.com/MatthiasvB/concurrent_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/MatthiasvB/concurrent_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMatthiasvB%2Fconcurrent_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMatthiasvB%2Fconcurrent_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c48d30a3929e27f6d34fceab0a9cbf2ddac18dcb
[INFO] checking MatthiasvB/concurrent_rust against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMatthiasvB%2Fconcurrent_rust" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/MatthiasvB/concurrent_rust 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 git repo https://github.com/MatthiasvB/concurrent_rust
[INFO] finished tweaking git repo https://github.com/MatthiasvB/concurrent_rust
[INFO] tweaked toml for git repo https://github.com/MatthiasvB/concurrent_rust written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/MatthiasvB/concurrent_rust already has a lockfile, it will not be regenerated
[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-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] f04f2654a6a621d9b560e0d4e08ea4e474b106d3b0a9f08542e787541c9c6101
[INFO] running `Command { std: "docker" "start" "-a" "f04f2654a6a621d9b560e0d4e08ea4e474b106d3b0a9f08542e787541c9c6101", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f04f2654a6a621d9b560e0d4e08ea4e474b106d3b0a9f08542e787541c9c6101", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f04f2654a6a621d9b560e0d4e08ea4e474b106d3b0a9f08542e787541c9c6101", kill_on_drop: false }`
[INFO] [stdout] f04f2654a6a621d9b560e0d4e08ea4e474b106d3b0a9f08542e787541c9c6101
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] c0275262c0fcd0b5253d6bea57d2f1bd5f10734d3047cbeebfb68a421a268aea
[INFO] running `Command { std: "docker" "start" "-a" "c0275262c0fcd0b5253d6bea57d2f1bd5f10734d3047cbeebfb68a421a268aea", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.147
[INFO] [stderr]    Compiling crossbeam-utils v0.8.16
[INFO] [stderr]    Compiling memoffset v0.9.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.15
[INFO] [stderr]    Compiling slab v0.4.9
[INFO] [stderr]    Compiling futures-util v0.3.28
[INFO] [stderr]    Compiling rayon-core v1.11.0
[INFO] [stderr]     Checking memchr v2.6.3
[INFO] [stderr]     Checking bytes v1.5.0
[INFO] [stderr]     Checking either v1.9.0
[INFO] [stderr]    Compiling syn v2.0.32
[INFO] [stderr]     Checking getrandom v0.2.10
[INFO] [stderr]     Checking num_cpus v1.16.0
[INFO] [stderr]     Checking parking_lot_core v0.9.8
[INFO] [stderr]     Checking socket2 v0.5.4
[INFO] [stderr]     Checking signal-hook-registry v1.4.1
[INFO] [stderr]     Checking mio v0.8.8
[INFO] [stderr]     Checking crossbeam-channel v0.5.8
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking parking_lot v0.12.1
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking crossbeam-deque v0.8.3
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking rayon v1.7.0
[INFO] [stderr]    Compiling futures-macro v0.3.28
[INFO] [stderr]    Compiling tokio-macros v2.1.0
[INFO] [stderr]     Checking tokio v1.32.0
[INFO] [stderr]     Checking futures-executor v0.3.28
[INFO] [stderr]     Checking futures v0.3.28
[INFO] [stderr]     Checking concurrent_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `futures` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use futures;
[INFO] [stdout]   |     ^^^^^^^ the item `futures` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `std` is imported redundantly
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std;
[INFO] [stdout]   |     ^^^ the item `std` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `tokio` is imported redundantly
[INFO] [stdout]  --> src/main.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use tokio;
[INFO] [stdout]   |     ^^^^^ the item `tokio` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `futures` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use futures;
[INFO] [stdout]   |     ^^^^^^^ the item `futures` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `std` is imported redundantly
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std;
[INFO] [stdout]   |     ^^^ the item `std` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `tokio` is imported redundantly
[INFO] [stdout]  --> src/main.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use tokio;
[INFO] [stdout]   |     ^^^^^ the item `tokio` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 5.94s
[INFO] running `Command { std: "docker" "inspect" "c0275262c0fcd0b5253d6bea57d2f1bd5f10734d3047cbeebfb68a421a268aea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c0275262c0fcd0b5253d6bea57d2f1bd5f10734d3047cbeebfb68a421a268aea", kill_on_drop: false }`
[INFO] [stdout] c0275262c0fcd0b5253d6bea57d2f1bd5f10734d3047cbeebfb68a421a268aea