[INFO] cloning repository https://github.com/ladislaff93/flat_map_implementation
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ladislaff93/flat_map_implementation" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fladislaff93%2Fflat_map_implementation", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fladislaff93%2Fflat_map_implementation'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 971d20f7e7daf42c1eb9c41b438332572bac82ec
[INFO] checking ladislaff93/flat_map_implementation against master#1f12b9b0fdbe735968ac002792a720f0ba4faca6 for crater-rollup-uwu
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fladislaff93%2Fflat_map_implementation" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ladislaff93/flat_map_implementation on toolchain 1f12b9b0fdbe735968ac002792a720f0ba4faca6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/ladislaff93/flat_map_implementation
[INFO] finished tweaking git repo https://github.com/ladislaff93/flat_map_implementation
[INFO] tweaked toml for git repo https://github.com/ladislaff93/flat_map_implementation written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/ladislaff93/flat_map_implementation 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" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6d34327fbb04e3c94eaf50e89bf9d77428892946e40f1069598606f54b88b0e4
[INFO] running `Command { std: "docker" "start" "-a" "6d34327fbb04e3c94eaf50e89bf9d77428892946e40f1069598606f54b88b0e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6d34327fbb04e3c94eaf50e89bf9d77428892946e40f1069598606f54b88b0e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6d34327fbb04e3c94eaf50e89bf9d77428892946e40f1069598606f54b88b0e4", kill_on_drop: false }`
[INFO] [stdout] 6d34327fbb04e3c94eaf50e89bf9d77428892946e40f1069598606f54b88b0e4
[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" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4a1e73847dfc684355bbeb02a47501adb6695c7c9c1290120e4b9a2e0957c749
[INFO] running `Command { std: "docker" "start" "-a" "4a1e73847dfc684355bbeb02a47501adb6695c7c9c1290120e4b9a2e0957c749", kill_on_drop: false }`
[INFO] [stderr]     Checking flat_map_implementation v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function `flat_map` is never used
[INFO] [stdout]  --> src/lib.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn flat_map<O,F,U>(iter: O, f: F) -> MySimpleIterator<O::IntoIter,F,U> 
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `MySimpleIterator` is never constructed
[INFO] [stdout]   --> src/lib.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct MySimpleIterator<O,F,U> 
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/lib.rs:28:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | / impl <O,F,U> MySimpleIterator<O,F,U>
[INFO] [stdout] 23 | | where 
[INFO] [stdout] 24 | |     O: Iterator,
[INFO] [stdout] 25 | |     U: IntoIterator,
[INFO] [stdout] 26 | |     F: FnMut(O::Item) -> U
[INFO] [stdout]    | |__________________________- associated function in this implementation
[INFO] [stdout] 27 |   {
[INFO] [stdout] 28 |       fn new(iter: O, f: F) -> Self {
[INFO] [stdout]    |          ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.06s
[INFO] running `Command { std: "docker" "inspect" "4a1e73847dfc684355bbeb02a47501adb6695c7c9c1290120e4b9a2e0957c749", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4a1e73847dfc684355bbeb02a47501adb6695c7c9c1290120e4b9a2e0957c749", kill_on_drop: false }`
[INFO] [stdout] 4a1e73847dfc684355bbeb02a47501adb6695c7c9c1290120e4b9a2e0957c749