[INFO] cloning repository https://github.com/chxry/rock
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/chxry/rock" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchxry%2Frock", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchxry%2Frock'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 23d2d2b77ec1131d2299ddbb8f3c042f9ee20ccb
[INFO] checking chxry/rock against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchxry%2Frock" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/chxry/rock 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/chxry/rock
[INFO] finished tweaking git repo https://github.com/chxry/rock
[INFO] tweaked toml for git repo https://github.com/chxry/rock written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/chxry/rock 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]  Downloading crates ...
[INFO] [stderr]   Downloaded cxxbridge-flags v1.0.79
[INFO] [stderr]   Downloaded scratch v1.0.2
[INFO] [stderr]   Downloaded link-cplusplus v1.0.7
[INFO] [stderr]   Downloaded iana-time-zone v0.1.51
[INFO] [stderr]   Downloaded cxxbridge-macro v1.0.79
[INFO] [stderr]   Downloaded cxx v1.0.79
[INFO] [stderr]   Downloaded cxx-build v1.0.79
[INFO] [stderr]   Downloaded libc v0.2.135
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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] d4950a267f0d81c5e6c0a73ba8b314510dc803a9478e572190a4b457b4e07ad9
[INFO] running `Command { std: "docker" "start" "-a" "d4950a267f0d81c5e6c0a73ba8b314510dc803a9478e572190a4b457b4e07ad9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d4950a267f0d81c5e6c0a73ba8b314510dc803a9478e572190a4b457b4e07ad9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d4950a267f0d81c5e6c0a73ba8b314510dc803a9478e572190a4b457b4e07ad9", kill_on_drop: false }`
[INFO] [stdout] d4950a267f0d81c5e6c0a73ba8b314510dc803a9478e572190a4b457b4e07ad9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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] 4ee56208138a16b583c2da96314b070d479d653ee656bda4c1220df45e72f016
[INFO] running `Command { std: "docker" "start" "-a" "4ee56208138a16b583c2da96314b070d479d653ee656bda4c1220df45e72f016", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.135
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]     Checking iana-time-zone v0.1.51
[INFO] [stderr]     Checking numtoa v0.1.0
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking termion v1.5.6
[INFO] [stderr]     Checking chrono v0.4.22
[INFO] [stderr]     Checking rock v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 57 |     stdout().flush();
[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] 57 |     let _ = stdout().flush();
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 57 |     stdout().flush();
[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] 57 |     let _ = stdout().flush();
[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 3.24s
[INFO] running `Command { std: "docker" "inspect" "4ee56208138a16b583c2da96314b070d479d653ee656bda4c1220df45e72f016", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4ee56208138a16b583c2da96314b070d479d653ee656bda4c1220df45e72f016", kill_on_drop: false }`
[INFO] [stdout] 4ee56208138a16b583c2da96314b070d479d653ee656bda4c1220df45e72f016
[INFO] checking chxry/rock against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchxry%2Frock" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/chxry/rock 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/chxry/rock
[INFO] finished tweaking git repo https://github.com/chxry/rock
[INFO] tweaked toml for git repo https://github.com/chxry/rock written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/chxry/rock 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-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 28a01192adddd457f2d187c11137150aec34c449ccc67c5d425fa26ef3d09dc5
[INFO] running `Command { std: "docker" "start" "-a" "28a01192adddd457f2d187c11137150aec34c449ccc67c5d425fa26ef3d09dc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "28a01192adddd457f2d187c11137150aec34c449ccc67c5d425fa26ef3d09dc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "28a01192adddd457f2d187c11137150aec34c449ccc67c5d425fa26ef3d09dc5", kill_on_drop: false }`
[INFO] [stdout] 28a01192adddd457f2d187c11137150aec34c449ccc67c5d425fa26ef3d09dc5
[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" "-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] c6ab1903f1bfa585473685f4a06bb0b1784459efbf379dd61ec104586b2b9461
[INFO] running `Command { std: "docker" "start" "-a" "c6ab1903f1bfa585473685f4a06bb0b1784459efbf379dd61ec104586b2b9461", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.135
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]     Checking numtoa v0.1.0
[INFO] [stderr]     Checking iana-time-zone v0.1.51
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking termion v1.5.6
[INFO] [stderr]     Checking chrono v0.4.22
[INFO] [stderr]     Checking rock v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 57 |     stdout().flush();
[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] 57 |     let _ = stdout().flush();
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 57 |     stdout().flush();
[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] 57 |     let _ = stdout().flush();
[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 3.09s
[INFO] running `Command { std: "docker" "inspect" "c6ab1903f1bfa585473685f4a06bb0b1784459efbf379dd61ec104586b2b9461", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c6ab1903f1bfa585473685f4a06bb0b1784459efbf379dd61ec104586b2b9461", kill_on_drop: false }`
[INFO] [stdout] c6ab1903f1bfa585473685f4a06bb0b1784459efbf379dd61ec104586b2b9461