[INFO] cloning repository https://github.com/laoer536/rust-learn
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/laoer536/rust-learn" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flaoer536%2Frust-learn", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flaoer536%2Frust-learn'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 28b75af155f3d99e8e9cabf4c09f164ba5827438
[INFO] checking laoer536/rust-learn against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flaoer536%2Frust-learn" "/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/laoer536/rust-learn 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/laoer536/rust-learn
[INFO] finished tweaking git repo https://github.com/laoer536/rust-learn
[INFO] tweaked toml for git repo https://github.com/laoer536/rust-learn written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/laoer536/rust-learn 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] 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] 49c09603f3adb4f06e660faee326d9db24dc2f022fd8d421e2ba9289a15c2b0b
[INFO] running `Command { std: "docker" "start" "-a" "49c09603f3adb4f06e660faee326d9db24dc2f022fd8d421e2ba9289a15c2b0b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "49c09603f3adb4f06e660faee326d9db24dc2f022fd8d421e2ba9289a15c2b0b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "49c09603f3adb4f06e660faee326d9db24dc2f022fd8d421e2ba9289a15c2b0b", kill_on_drop: false }`
[INFO] [stdout] 49c09603f3adb4f06e660faee326d9db24dc2f022fd8d421e2ba9289a15c2b0b
[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] 7745792e2d1f7dc9cc5dbd5d58b4a9f9301f04bb5dd5bce5d36f89654aa3960d
[INFO] running `Command { std: "docker" "start" "-a" "7745792e2d1f7dc9cc5dbd5d58b4a9f9301f04bb5dd5bce5d36f89654aa3960d", kill_on_drop: false }`
[INFO] [stderr]    Compiling wasm-bindgen-shared v0.2.91
[INFO] [stderr]    Compiling bumpalo v3.15.3
[INFO] [stderr]    Compiling wasm-bindgen v0.2.91
[INFO] [stderr]    Compiling syn v2.0.51
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.91
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.91
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.91
[INFO] [stderr]     Checking console_error_panic_hook v0.1.7
[INFO] [stderr]     Checking rust-learn v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function `set_panic_hook` is never used
[INFO] [stdout]  --> src/utils.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn set_panic_hook() {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `set_panic_hook` is never used
[INFO] [stdout]  --> src/utils.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn set_panic_hook() {
[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] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 10.87s
[INFO] running `Command { std: "docker" "inspect" "7745792e2d1f7dc9cc5dbd5d58b4a9f9301f04bb5dd5bce5d36f89654aa3960d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7745792e2d1f7dc9cc5dbd5d58b4a9f9301f04bb5dd5bce5d36f89654aa3960d", kill_on_drop: false }`
[INFO] [stdout] 7745792e2d1f7dc9cc5dbd5d58b4a9f9301f04bb5dd5bce5d36f89654aa3960d
[INFO] checking laoer536/rust-learn against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flaoer536%2Frust-learn" "/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/laoer536/rust-learn 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/laoer536/rust-learn
[INFO] finished tweaking git repo https://github.com/laoer536/rust-learn
[INFO] tweaked toml for git repo https://github.com/laoer536/rust-learn written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/laoer536/rust-learn 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-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] f6280a90aed1c8951cfd8642556288f8cece666c9363317fd2c3a1fd55249988
[INFO] running `Command { std: "docker" "start" "-a" "f6280a90aed1c8951cfd8642556288f8cece666c9363317fd2c3a1fd55249988", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f6280a90aed1c8951cfd8642556288f8cece666c9363317fd2c3a1fd55249988", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f6280a90aed1c8951cfd8642556288f8cece666c9363317fd2c3a1fd55249988", kill_on_drop: false }`
[INFO] [stdout] f6280a90aed1c8951cfd8642556288f8cece666c9363317fd2c3a1fd55249988
[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] 660d508e9817abf1bf937c3b3fc9fe3c2d4cbf4d9f05bd360f7ceadeb991d8fe
[INFO] running `Command { std: "docker" "start" "-a" "660d508e9817abf1bf937c3b3fc9fe3c2d4cbf4d9f05bd360f7ceadeb991d8fe", kill_on_drop: false }`
[INFO] [stderr]    Compiling wasm-bindgen-shared v0.2.91
[INFO] [stderr]    Compiling syn v2.0.51
[INFO] [stderr]    Compiling bumpalo v3.15.3
[INFO] [stderr]    Compiling wasm-bindgen v0.2.91
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.91
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.91
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.91
[INFO] [stderr]     Checking console_error_panic_hook v0.1.7
[INFO] [stderr]     Checking rust-learn v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function `set_panic_hook` is never used
[INFO] [stdout]  --> src/utils.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn set_panic_hook() {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `set_panic_hook` is never used
[INFO] [stdout]  --> src/utils.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn set_panic_hook() {
[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] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 10.66s
[INFO] running `Command { std: "docker" "inspect" "660d508e9817abf1bf937c3b3fc9fe3c2d4cbf4d9f05bd360f7ceadeb991d8fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "660d508e9817abf1bf937c3b3fc9fe3c2d4cbf4d9f05bd360f7ceadeb991d8fe", kill_on_drop: false }`
[INFO] [stdout] 660d508e9817abf1bf937c3b3fc9fe3c2d4cbf4d9f05bd360f7ceadeb991d8fe