[INFO] cloning repository https://github.com/popey456963/lingo
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/popey456963/lingo" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpopey456963%2Flingo", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpopey456963%2Flingo'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 49682c180974983fd7afeef50784dcca4b9030b2
[INFO] checking popey456963/lingo against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpopey456963%2Flingo" "/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/popey456963/lingo 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] removed /workspace/builds/worker-7-tc1/source/.cargo/config.toml
[INFO] started tweaking git repo https://github.com/popey456963/lingo
[INFO] finished tweaking git repo https://github.com/popey456963/lingo
[INFO] tweaked toml for git repo https://github.com/popey456963/lingo written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/popey456963/lingo 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] [stderr] warning: unused manifest key: unstable
[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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e68d0ed32c7b367a020705773f16a51138ffabf09f29e85105cfca86a85a96eb
[INFO] running `Command { std: "docker" "start" "-a" "e68d0ed32c7b367a020705773f16a51138ffabf09f29e85105cfca86a85a96eb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e68d0ed32c7b367a020705773f16a51138ffabf09f29e85105cfca86a85a96eb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e68d0ed32c7b367a020705773f16a51138ffabf09f29e85105cfca86a85a96eb", kill_on_drop: false }`
[INFO] [stdout] e68d0ed32c7b367a020705773f16a51138ffabf09f29e85105cfca86a85a96eb
[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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 91e1315481da8d27bfa7390ded30d9a71d4322724fe23463e4d489b3daee12f5
[INFO] running `Command { std: "docker" "start" "-a" "91e1315481da8d27bfa7390ded30d9a71d4322724fe23463e4d489b3daee12f5", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: unstable
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking crossbeam-channel v0.5.1
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]     Checking lingo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function `read_u8_from_stdin` is never used
[INFO] [stdout]   --> src/main.rs:88:4
[INFO] [stdout]    |
[INFO] [stdout] 88 | fn read_u8_from_stdin() -> u8 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `c` is never used
[INFO] [stdout]    --> src/main.rs:135:4
[INFO] [stdout]     |
[INFO] [stdout] 135 | fn c(a: &str) -> Vec<char> {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_u8_from_stdin` is never used
[INFO] [stdout]   --> src/main.rs:88:4
[INFO] [stdout]    |
[INFO] [stdout] 88 | fn read_u8_from_stdin() -> u8 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.79s
[INFO] running `Command { std: "docker" "inspect" "91e1315481da8d27bfa7390ded30d9a71d4322724fe23463e4d489b3daee12f5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "91e1315481da8d27bfa7390ded30d9a71d4322724fe23463e4d489b3daee12f5", kill_on_drop: false }`
[INFO] [stdout] 91e1315481da8d27bfa7390ded30d9a71d4322724fe23463e4d489b3daee12f5
[INFO] checking popey456963/lingo against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpopey456963%2Flingo" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/popey456963/lingo 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] removed /workspace/builds/worker-7-tc2/source/.cargo/config.toml
[INFO] started tweaking git repo https://github.com/popey456963/lingo
[INFO] finished tweaking git repo https://github.com/popey456963/lingo
[INFO] tweaked toml for git repo https://github.com/popey456963/lingo written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/popey456963/lingo 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] [stderr] warning: unused manifest key: unstable
[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-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] 6b39a458f7fd66b192d8df640a7cc1163768ced569c95ae94ffadbfb59413140
[INFO] running `Command { std: "docker" "start" "-a" "6b39a458f7fd66b192d8df640a7cc1163768ced569c95ae94ffadbfb59413140", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6b39a458f7fd66b192d8df640a7cc1163768ced569c95ae94ffadbfb59413140", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b39a458f7fd66b192d8df640a7cc1163768ced569c95ae94ffadbfb59413140", kill_on_drop: false }`
[INFO] [stdout] 6b39a458f7fd66b192d8df640a7cc1163768ced569c95ae94ffadbfb59413140
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] 3512a5b7cdcfde7b0d36d9f4cf2349a04d5ecf72f3c58f53f843c99c386b68a4
[INFO] running `Command { std: "docker" "start" "-a" "3512a5b7cdcfde7b0d36d9f4cf2349a04d5ecf72f3c58f53f843c99c386b68a4", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: unstable
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking crossbeam-channel v0.5.1
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]     Checking lingo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function `read_u8_from_stdin` is never used
[INFO] [stdout]   --> src/main.rs:88:4
[INFO] [stdout]    |
[INFO] [stdout] 88 | fn read_u8_from_stdin() -> u8 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `c` is never used
[INFO] [stdout]    --> src/main.rs:135:4
[INFO] [stdout]     |
[INFO] [stdout] 135 | fn c(a: &str) -> Vec<char> {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_u8_from_stdin` is never used
[INFO] [stdout]   --> src/main.rs:88:4
[INFO] [stdout]    |
[INFO] [stdout] 88 | fn read_u8_from_stdin() -> u8 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.89s
[INFO] running `Command { std: "docker" "inspect" "3512a5b7cdcfde7b0d36d9f4cf2349a04d5ecf72f3c58f53f843c99c386b68a4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3512a5b7cdcfde7b0d36d9f4cf2349a04d5ecf72f3c58f53f843c99c386b68a4", kill_on_drop: false }`
[INFO] [stdout] 3512a5b7cdcfde7b0d36d9f4cf2349a04d5ecf72f3c58f53f843c99c386b68a4