[INFO] cloning repository https://github.com/timbby/substrate_course_4
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/timbby/substrate_course_4" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftimbby%2Fsubstrate_course_4", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftimbby%2Fsubstrate_course_4'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8976134fc673f3d4975ad26f22324144396e0e22
[INFO] checking timbby/substrate_course_4 against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftimbby%2Fsubstrate_course_4" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/timbby/substrate_course_4 on toolchain ceab6128fa48a616bfd3e3adf4bc80133b8ee223
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/timbby/substrate_course_4
[INFO] finished tweaking git repo https://github.com/timbby/substrate_course_4
[INFO] tweaked toml for git repo https://github.com/timbby/substrate_course_4 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/timbby/substrate_course_4 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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[ERROR] error running command: no output for 300 seconds
[ERROR] this task or one of its parent failed!
[ERROR] no output for 300 seconds
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.
[INFO] checking timbby/substrate_course_4 against try#3a4bc97f6385a3aa300a4fd689b44350e54fd676 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftimbby%2Fsubstrate_course_4" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/timbby/substrate_course_4 on toolchain 3a4bc97f6385a3aa300a4fd689b44350e54fd676
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/timbby/substrate_course_4
[INFO] finished tweaking git repo https://github.com/timbby/substrate_course_4
[INFO] tweaked toml for git repo https://github.com/timbby/substrate_course_4 written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/timbby/substrate_course_4 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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "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-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 921cca24c03c63793d061bb5cad837661eeb460804a418e328451c271f68c100
[INFO] running `Command { std: "docker" "start" "-a" "921cca24c03c63793d061bb5cad837661eeb460804a418e328451c271f68c100", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "921cca24c03c63793d061bb5cad837661eeb460804a418e328451c271f68c100", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "921cca24c03c63793d061bb5cad837661eeb460804a418e328451c271f68c100", kill_on_drop: false }`
[INFO] [stdout] 921cca24c03c63793d061bb5cad837661eeb460804a418e328451c271f68c100
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a96f15e0d80bd18045be339b0f204729d44a38bfe5095530e5342fb3f613ebc7
[INFO] running `Command { std: "docker" "start" "-a" "a96f15e0d80bd18045be339b0f204729d44a38bfe5095530e5342fb3f613ebc7", kill_on_drop: false }`
[INFO] [stderr]     Checking substrate_course_4 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variants `Green` and `Yellow` are never constructed
[INFO] [stdout]   --> src/test.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 8  | enum TrafficLight {
[INFO] [stdout]    |      ------------ variants in this enum
[INFO] [stdout] 9  |     Red,
[INFO] [stdout] 10 |     Green,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 11 |     Yellow,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `x` and `y` are never read
[INFO] [stdout]    --> src/test.rs:135:9
[INFO] [stdout]     |
[INFO] [stdout] 134 |     struct Point<T> {
[INFO] [stdout]     |            ----- fields in this struct
[INFO] [stdout] 135 |         x: T,
[INFO] [stdout]     |         ^
[INFO] [stdout] 136 |         y: T,
[INFO] [stdout]     |         ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `Point` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `x` is never used
[INFO] [stdout]    --> src/test.rs:140:12
[INFO] [stdout]     |
[INFO] [stdout] 139 |     impl<T> Point<T> {
[INFO] [stdout]     |     ---------------- method in this implementation
[INFO] [stdout] 140 |         fn x(&self) -> &T {
[INFO] [stdout]     |            ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Green` and `Yellow` are never constructed
[INFO] [stdout]   --> src/test.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 8  | enum TrafficLight {
[INFO] [stdout]    |      ------------ variants in this enum
[INFO] [stdout] 9  |     Red,
[INFO] [stdout] 10 |     Green,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 11 |     Yellow,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `x` and `y` are never read
[INFO] [stdout]    --> src/test.rs:135:9
[INFO] [stdout]     |
[INFO] [stdout] 134 |     struct Point<T> {
[INFO] [stdout]     |            ----- fields in this struct
[INFO] [stdout] 135 |         x: T,
[INFO] [stdout]     |         ^
[INFO] [stdout] 136 |         y: T,
[INFO] [stdout]     |         ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `Point` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `x` is never used
[INFO] [stdout]    --> src/test.rs:140:12
[INFO] [stdout]     |
[INFO] [stdout] 139 |     impl<T> Point<T> {
[INFO] [stdout]     |     ---------------- method in this implementation
[INFO] [stdout] 140 |         fn x(&self) -> &T {
[INFO] [stdout]     |            ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.09s
[INFO] running `Command { std: "docker" "inspect" "a96f15e0d80bd18045be339b0f204729d44a38bfe5095530e5342fb3f613ebc7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a96f15e0d80bd18045be339b0f204729d44a38bfe5095530e5342fb3f613ebc7", kill_on_drop: false }`
[INFO] [stdout] a96f15e0d80bd18045be339b0f204729d44a38bfe5095530e5342fb3f613ebc7