[INFO] cloning repository https://github.com/amitbikram/ru_conc
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/amitbikram/ru_conc" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famitbikram%2Fru_conc", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famitbikram%2Fru_conc'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5e1f5e7a951122951a9637bcd47b9b42e1faa0ef
[INFO] checking amitbikram/ru_conc against master#dfd7b8d03fb93d0e03147d28b3be6d93260fa94d for pr-87050
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famitbikram%2Fru_conc" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/amitbikram/ru_conc on toolchain dfd7b8d03fb93d0e03147d28b3be6d93260fa94d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/amitbikram/ru_conc
[INFO] finished tweaking git repo https://github.com/amitbikram/ru_conc
[INFO] tweaked toml for git repo https://github.com/amitbikram/ru_conc written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/amitbikram/ru_conc already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "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-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e4b659e2b76af591527d94db94d670520495db1bdef9299c422f79f0685ed3b6
[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" "e4b659e2b76af591527d94db94d670520495db1bdef9299c422f79f0685ed3b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e4b659e2b76af591527d94db94d670520495db1bdef9299c422f79f0685ed3b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e4b659e2b76af591527d94db94d670520495db1bdef9299c422f79f0685ed3b6", kill_on_drop: false }`
[INFO] [stdout] e4b659e2b76af591527d94db94d670520495db1bdef9299c422f79f0685ed3b6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 140c60498c5362a82d51e5780d6c701198fcf0440bfcf8557e1bf59740beca5b
[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" "140c60498c5362a82d51e5780d6c701198fcf0440bfcf8557e1bf59740beca5b", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.70
[INFO] [stderr]    Compiling memchr v2.3.4
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling futures-macro v0.3.14
[INFO] [stderr]     Checking futures-util v0.3.14
[INFO] [stderr]     Checking futures-executor v0.3.14
[INFO] [stderr]     Checking futures v0.3.14
[INFO] [stderr]     Checking ru_conc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let mut state  = State {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let mut state  = State {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 27.39s
[INFO] running `Command { std: "docker" "inspect" "140c60498c5362a82d51e5780d6c701198fcf0440bfcf8557e1bf59740beca5b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "140c60498c5362a82d51e5780d6c701198fcf0440bfcf8557e1bf59740beca5b", kill_on_drop: false }`
[INFO] [stdout] 140c60498c5362a82d51e5780d6c701198fcf0440bfcf8557e1bf59740beca5b