[INFO] cloning repository https://github.com/Fedor-Bystrov/pngr
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Fedor-Bystrov/pngr" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFedor-Bystrov%2Fpngr", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFedor-Bystrov%2Fpngr'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ce9f163f22c111d8324c731f6f20b6d8a2781a44
[INFO] checking Fedor-Bystrov/pngr 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%2FFedor-Bystrov%2Fpngr" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/Fedor-Bystrov/pngr
[INFO] finished tweaking git repo https://github.com/Fedor-Bystrov/pngr
[INFO] tweaked toml for git repo https://github.com/Fedor-Bystrov/pngr written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/Fedor-Bystrov/pngr 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/Fedor-Bystrov/pngr 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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] 34d209a721232784ea16681faf1fc3d4445b4a77fdb9b5c95ef74b7558a8ce28
[INFO] running `Command { std: "docker" "start" "-a" "34d209a721232784ea16681faf1fc3d4445b4a77fdb9b5c95ef74b7558a8ce28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "34d209a721232784ea16681faf1fc3d4445b4a77fdb9b5c95ef74b7558a8ce28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "34d209a721232784ea16681faf1fc3d4445b4a77fdb9b5c95ef74b7558a8ce28", kill_on_drop: false }`
[INFO] [stdout] 34d209a721232784ea16681faf1fc3d4445b4a77fdb9b5c95ef74b7558a8ce28
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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] 4b4603ec8f77e67213f211fa68732e376b1299de363a820264387619138b0274
[INFO] running `Command { std: "docker" "start" "-a" "4b4603ec8f77e67213f211fa68732e376b1299de363a820264387619138b0274", kill_on_drop: false }`
[INFO] [stderr]    Compiling crc32fast v1.3.2
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]     Checking miniz_oxide v0.5.3
[INFO] [stderr]     Checking flate2 v1.0.24
[INFO] [stderr]     Checking pngr v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: this type will no longer be must used: Result<Vec<u8>, Infallible>
[INFO] [stdout]   --> src/lib.rs:27:44
[INFO] [stdout]    |
[INFO] [stdout] 27 |         let chunk_type = String::from_utf8(chunk_data[4..8].try_into().unwrap()).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<Vec<u8>, Infallible>
[INFO] [stdout]   --> src/lib.rs:27:44
[INFO] [stdout]    |
[INFO] [stdout] 27 |         let chunk_type = String::from_utf8(chunk_data[4..8].try_into().unwrap()).unwrap();
[INFO] [stdout]    |                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `pngr` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `pngr` (lib test) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "4b4603ec8f77e67213f211fa68732e376b1299de363a820264387619138b0274", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b4603ec8f77e67213f211fa68732e376b1299de363a820264387619138b0274", kill_on_drop: false }`
[INFO] [stdout] 4b4603ec8f77e67213f211fa68732e376b1299de363a820264387619138b0274