[INFO] cloning repository https://github.com/sebasmagri/rust-concurrency-patterns
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sebasmagri/rust-concurrency-patterns" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsebasmagri%2Frust-concurrency-patterns", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsebasmagri%2Frust-concurrency-patterns'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c916fe831faec73a7fb5d652e91fa9da528d85c4
[INFO] checking sebasmagri/rust-concurrency-patterns against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsebasmagri%2Frust-concurrency-patterns" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sebasmagri/rust-concurrency-patterns on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sebasmagri/rust-concurrency-patterns
[INFO] finished tweaking git repo https://github.com/sebasmagri/rust-concurrency-patterns
[INFO] tweaked toml for git repo https://github.com/sebasmagri/rust-concurrency-patterns written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/sebasmagri/rust-concurrency-patterns 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 56024a1d4d86504dcda2b149f6ef26a5d5fd67b53f4a080c6f62775128ab2ee9
[INFO] running `Command { std: "docker" "start" "-a" "56024a1d4d86504dcda2b149f6ef26a5d5fd67b53f4a080c6f62775128ab2ee9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "56024a1d4d86504dcda2b149f6ef26a5d5fd67b53f4a080c6f62775128ab2ee9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "56024a1d4d86504dcda2b149f6ef26a5d5fd67b53f4a080c6f62775128ab2ee9", kill_on_drop: false }`
[INFO] [stdout] 56024a1d4d86504dcda2b149f6ef26a5d5fd67b53f4a080c6f62775128ab2ee9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b2c31962352850770f9301b4ba75933a983ec0786e042317bbdace5903b4a179
[INFO] running `Command { std: "docker" "start" "-a" "b2c31962352850770f9301b4ba75933a983ec0786e042317bbdace5903b4a179", kill_on_drop: false }`
[INFO] [stderr]     Checking concurrency-patterns v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/04-fan-in.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 32 |     consumer(Arc::new(Mutex::new(rx))).join();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let _ = consumer(Arc::new(Mutex::new(rx))).join();
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.24s
[INFO] running `Command { std: "docker" "inspect" "b2c31962352850770f9301b4ba75933a983ec0786e042317bbdace5903b4a179", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b2c31962352850770f9301b4ba75933a983ec0786e042317bbdace5903b4a179", kill_on_drop: false }`
[INFO] [stdout] b2c31962352850770f9301b4ba75933a983ec0786e042317bbdace5903b4a179
[INFO] checking sebasmagri/rust-concurrency-patterns against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsebasmagri%2Frust-concurrency-patterns" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sebasmagri/rust-concurrency-patterns on toolchain 2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sebasmagri/rust-concurrency-patterns
[INFO] finished tweaking git repo https://github.com/sebasmagri/rust-concurrency-patterns
[INFO] tweaked toml for git repo https://github.com/sebasmagri/rust-concurrency-patterns written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/sebasmagri/rust-concurrency-patterns 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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ad49df523dad732c1ae8756f6ae707b09d8d06df74cb82894b5079707e2ae50d
[INFO] running `Command { std: "docker" "start" "-a" "ad49df523dad732c1ae8756f6ae707b09d8d06df74cb82894b5079707e2ae50d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ad49df523dad732c1ae8756f6ae707b09d8d06df74cb82894b5079707e2ae50d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ad49df523dad732c1ae8756f6ae707b09d8d06df74cb82894b5079707e2ae50d", kill_on_drop: false }`
[INFO] [stdout] ad49df523dad732c1ae8756f6ae707b09d8d06df74cb82894b5079707e2ae50d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 556e33672ff6734e35d3eb4be6af222c23f20c8084b65c959b98dfa1845e4ca3
[INFO] running `Command { std: "docker" "start" "-a" "556e33672ff6734e35d3eb4be6af222c23f20c8084b65c959b98dfa1845e4ca3", kill_on_drop: false }`
[INFO] [stderr]     Checking concurrency-patterns v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/04-fan-in.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 32 |     consumer(Arc::new(Mutex::new(rx))).join();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let _ = consumer(Arc::new(Mutex::new(rx))).join();
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.21s
[INFO] running `Command { std: "docker" "inspect" "556e33672ff6734e35d3eb4be6af222c23f20c8084b65c959b98dfa1845e4ca3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "556e33672ff6734e35d3eb4be6af222c23f20c8084b65c959b98dfa1845e4ca3", kill_on_drop: false }`
[INFO] [stdout] 556e33672ff6734e35d3eb4be6af222c23f20c8084b65c959b98dfa1845e4ca3