[INFO] cloning repository https://github.com/yangcancai/hello_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/yangcancai/hello_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyangcancai%2Fhello_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyangcancai%2Fhello_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e88d80e733790b50adbc195f1caf859fca359046
[INFO] checking yangcancai/hello_rust against master#4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5 for pr-81174
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyangcancai%2Fhello_rust" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/yangcancai/hello_rust on toolchain 4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/yangcancai/hello_rust
[INFO] finished tweaking git repo https://github.com/yangcancai/hello_rust
[INFO] tweaked toml for git repo https://github.com/yangcancai/hello_rust written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/yangcancai/hello_rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] d1447e86bcfd86cd149fba9f010de4f01da60a1d229d14a8afd04bcab8ab34ec
[INFO] running `Command { std: "docker" "start" "-a" "d1447e86bcfd86cd149fba9f010de4f01da60a1d229d14a8afd04bcab8ab34ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d1447e86bcfd86cd149fba9f010de4f01da60a1d229d14a8afd04bcab8ab34ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d1447e86bcfd86cd149fba9f010de4f01da60a1d229d14a8afd04bcab8ab34ec", kill_on_drop: false }`
[INFO] [stdout] d1447e86bcfd86cd149fba9f010de4f01da60a1d229d14a8afd04bcab8ab34ec
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 488376a71b13003f685d59c08c464079a16d4efa8a54a03340ba4890b5a64338
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "488376a71b13003f685d59c08c464079a16d4efa8a54a03340ba4890b5a64338", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.80
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]     Checking guess_game v0.1.0 (/opt/rustwide/workdir/guess_game)
[INFO] [stderr]     Checking hello_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `b`
[INFO] [stdout]    --> src/lib.rs:221:5
[INFO] [stdout]     |
[INFO] [stdout] 221 |     b: &'a P
[INFO] [stdout]     |     ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:215:8
[INFO] [stdout]     |
[INFO] [stdout] 215 | #[warn(dead_code)]
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `b`
[INFO] [stdout]    --> src/lib.rs:221:5
[INFO] [stdout]     |
[INFO] [stdout] 221 |     b: &'a P
[INFO] [stdout]     |     ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:215:8
[INFO] [stdout]     |
[INFO] [stdout] 215 | #[warn(dead_code)]
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `b`
[INFO] [stdout]    --> src/lib.rs:221:5
[INFO] [stdout]     |
[INFO] [stdout] 221 |     b: &'a P
[INFO] [stdout]     |     ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:215:8
[INFO] [stdout]     |
[INFO] [stdout] 215 | #[warn(dead_code)]
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Context`
[INFO] [stdout]    --> src/lib.rs:370:16
[INFO] [stdout]     |
[INFO] [stdout] 370 |     pub struct Context<T: Task>{
[INFO] [stdout]     |                ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `run`
[INFO] [stdout]    --> src/lib.rs:374:16
[INFO] [stdout]     |
[INFO] [stdout] 374 |         pub fn run(&self){
[INFO] [stdout]     |                ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `install`
[INFO] [stdout]    --> src/lib.rs:379:16
[INFO] [stdout]     |
[INFO] [stdout] 379 |         pub fn install(&mut self, plug: T){
[INFO] [stdout]     |                ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `b`
[INFO] [stdout]    --> src/lib.rs:221:5
[INFO] [stdout]     |
[INFO] [stdout] 221 |     b: &'a P
[INFO] [stdout]     |     ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:215:8
[INFO] [stdout]     |
[INFO] [stdout] 215 | #[warn(dead_code)]
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Context`
[INFO] [stdout]    --> src/lib.rs:370:16
[INFO] [stdout]     |
[INFO] [stdout] 370 |     pub struct Context<T: Task>{
[INFO] [stdout]     |                ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `run`
[INFO] [stdout]    --> src/lib.rs:374:16
[INFO] [stdout]     |
[INFO] [stdout] 374 |         pub fn run(&self){
[INFO] [stdout]     |                ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `install`
[INFO] [stdout]    --> src/lib.rs:379:16
[INFO] [stdout]     |
[INFO] [stdout] 379 |         pub fn install(&mut self, plug: T){
[INFO] [stdout]     |                ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.94s
[INFO] running `Command { std: "docker" "inspect" "488376a71b13003f685d59c08c464079a16d4efa8a54a03340ba4890b5a64338", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "488376a71b13003f685d59c08c464079a16d4efa8a54a03340ba4890b5a64338", kill_on_drop: false }`
[INFO] [stdout] 488376a71b13003f685d59c08c464079a16d4efa8a54a03340ba4890b5a64338