[INFO] cloning repository https://github.com/takechee/rust-livecording
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/takechee/rust-livecording" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftakechee%2Frust-livecording", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftakechee%2Frust-livecording'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9f336c8e7fe1db771e3f43f41a5a7b6d8ccb99ce
[INFO] checking takechee/rust-livecording against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftakechee%2Frust-livecording" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/takechee/rust-livecording 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/takechee/rust-livecording
[INFO] finished tweaking git repo https://github.com/takechee/rust-livecording
[INFO] tweaked toml for git repo https://github.com/takechee/rust-livecording written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/takechee/rust-livecording 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]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 1227df11bb119d23dd1231bab02c64884237bf1a633c61650a178b7ac1fc40f5
[INFO] running `Command { std: "docker" "start" "-a" "1227df11bb119d23dd1231bab02c64884237bf1a633c61650a178b7ac1fc40f5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1227df11bb119d23dd1231bab02c64884237bf1a633c61650a178b7ac1fc40f5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1227df11bb119d23dd1231bab02c64884237bf1a633c61650a178b7ac1fc40f5", kill_on_drop: false }`
[INFO] [stdout] 1227df11bb119d23dd1231bab02c64884237bf1a633c61650a178b7ac1fc40f5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 4b82e7d3753ec13069fb7d4052e5d6752aeb518178793b7269ee5c856f522008
[INFO] running `Command { std: "docker" "start" "-a" "4b82e7d3753ec13069fb7d4052e5d6752aeb518178793b7269ee5c856f522008", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.86
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]     Checking livecording v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Err` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::result::Result::Err;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/385fa9d845dd326c6bbfd58c22244215e431948a/library/std/src/prelude/mod.rs:134:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Err` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Err` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::result::Result::Err;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/385fa9d845dd326c6bbfd58c22244215e431948a/library/std/src/prelude/mod.rs:134:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Err` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` 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 1.85s
[INFO] running `Command { std: "docker" "inspect" "4b82e7d3753ec13069fb7d4052e5d6752aeb518178793b7269ee5c856f522008", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b82e7d3753ec13069fb7d4052e5d6752aeb518178793b7269ee5c856f522008", kill_on_drop: false }`
[INFO] [stdout] 4b82e7d3753ec13069fb7d4052e5d6752aeb518178793b7269ee5c856f522008
[INFO] checking takechee/rust-livecording against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftakechee%2Frust-livecording" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/takechee/rust-livecording 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/takechee/rust-livecording
[INFO] finished tweaking git repo https://github.com/takechee/rust-livecording
[INFO] tweaked toml for git repo https://github.com/takechee/rust-livecording written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/takechee/rust-livecording 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]     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-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 34a041d6b9452b51b6d7c13e2c44fe96f7a4053754ba3850420d401a00a93a9f
[INFO] running `Command { std: "docker" "start" "-a" "34a041d6b9452b51b6d7c13e2c44fe96f7a4053754ba3850420d401a00a93a9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "34a041d6b9452b51b6d7c13e2c44fe96f7a4053754ba3850420d401a00a93a9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "34a041d6b9452b51b6d7c13e2c44fe96f7a4053754ba3850420d401a00a93a9f", kill_on_drop: false }`
[INFO] [stdout] 34a041d6b9452b51b6d7c13e2c44fe96f7a4053754ba3850420d401a00a93a9f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 7be9eb5c8f498fd716c40373593e877b4b8105b5c93f8ea88a4c255a158ef6a6
[INFO] running `Command { std: "docker" "start" "-a" "7be9eb5c8f498fd716c40373593e877b4b8105b5c93f8ea88a4c255a158ef6a6", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.86
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]     Checking livecording v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Err` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::result::Result::Err;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2/library/std/src/prelude/mod.rs:134:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Err` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Err` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::result::Result::Err;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2/library/std/src/prelude/mod.rs:134:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Err` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` 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 2.01s
[INFO] running `Command { std: "docker" "inspect" "7be9eb5c8f498fd716c40373593e877b4b8105b5c93f8ea88a4c255a158ef6a6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7be9eb5c8f498fd716c40373593e877b4b8105b5c93f8ea88a4c255a158ef6a6", kill_on_drop: false }`
[INFO] [stdout] 7be9eb5c8f498fd716c40373593e877b4b8105b5c93f8ea88a4c255a158ef6a6