[INFO] cloning repository https://github.com/Sarath191181208/learning_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Sarath191181208/learning_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSarath191181208%2Flearning_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSarath191181208%2Flearning_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5426edef82532fd0fdf409c70db2dae5091c60d4
[INFO] checking Sarath191181208/learning_rust against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSarath191181208%2Flearning_rust" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/Sarath191181208/learning_rust
[INFO] finished tweaking git repo https://github.com/Sarath191181208/learning_rust
[INFO] tweaked toml for git repo https://github.com/Sarath191181208/learning_rust written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/Sarath191181208/learning_rust on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/Sarath191181208/learning_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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 24434856a77c8c978c566443f782fe60bafe92b1198632baf17a9180c8dcb546
[INFO] running `Command { std: "docker" "start" "-a" "24434856a77c8c978c566443f782fe60bafe92b1198632baf17a9180c8dcb546", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "24434856a77c8c978c566443f782fe60bafe92b1198632baf17a9180c8dcb546", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "24434856a77c8c978c566443f782fe60bafe92b1198632baf17a9180c8dcb546", kill_on_drop: false }`
[INFO] [stdout] 24434856a77c8c978c566443f782fe60bafe92b1198632baf17a9180c8dcb546
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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 -Dunmustuse_in_always_ok" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c953a1942078a5e2d204f8826442d3921cea7e65a5626d0d3271ed0503a8fa18
[INFO] running `Command { std: "docker" "start" "-a" "c953a1942078a5e2d204f8826442d3921cea7e65a5626d0d3271ed0503a8fa18", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v0.1.8
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_jitter v0.1.4
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking colored v2.0.0
[INFO] [stderr]     Checking rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: this type will no longer be must used: Result<usize, Infallible>
[INFO] [stdout]   --> src/connect_four/board_handler.rs:41:29
[INFO] [stdout]    |
[INFO] [stdout] 41 |         let col_no: usize = col_no.try_into().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<usize, Infallible>
[INFO] [stdout]   --> src/connect_four/board_handler.rs:89:29
[INFO] [stdout]    |
[INFO] [stdout] 89 |         let row_no: usize = row_idx.try_into().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<usize, Infallible>
[INFO] [stdout]   --> src/connect_four/board_handler.rs:41:29
[INFO] [stdout]    |
[INFO] [stdout] 41 |         let col_no: usize = col_no.try_into().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<usize, Infallible>
[INFO] [stdout]   --> src/connect_four/board_handler.rs:89:29
[INFO] [stdout]    |
[INFO] [stdout] 89 |         let row_no: usize = row_idx.try_into().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust` (bin "rust") due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `rust` (bin "rust" test) due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "c953a1942078a5e2d204f8826442d3921cea7e65a5626d0d3271ed0503a8fa18", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c953a1942078a5e2d204f8826442d3921cea7e65a5626d0d3271ed0503a8fa18", kill_on_drop: false }`
[INFO] [stdout] c953a1942078a5e2d204f8826442d3921cea7e65a5626d0d3271ed0503a8fa18