[INFO] cloning repository https://github.com/cj495840252/async-test
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/cj495840252/async-test" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcj495840252%2Fasync-test", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcj495840252%2Fasync-test'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ad829bb4ad05c146d065fccf22bfadb8416212a4
[INFO] checking cj495840252/async-test/ad829bb4ad05c146d065fccf22bfadb8416212a4 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcj495840252%2Fasync-test" "/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/cj495840252/async-test on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/cj495840252/async-test
[INFO] finished tweaking git repo https://github.com/cj495840252/async-test
[INFO] tweaked toml for git repo https://github.com/cj495840252/async-test written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/cj495840252/async-test 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" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d7b4f234174dff79ab4694e030c3b4abd3f7bdce9c016b9a5c2ccd49a9f14cd7
[INFO] running `Command { std: "docker" "start" "-a" "d7b4f234174dff79ab4694e030c3b4abd3f7bdce9c016b9a5c2ccd49a9f14cd7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d7b4f234174dff79ab4694e030c3b4abd3f7bdce9c016b9a5c2ccd49a9f14cd7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d7b4f234174dff79ab4694e030c3b4abd3f7bdce9c016b9a5c2ccd49a9f14cd7", kill_on_drop: false }`
[INFO] [stdout] d7b4f234174dff79ab4694e030c3b4abd3f7bdce9c016b9a5c2ccd49a9f14cd7
[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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fd106f36102d288a71051f4f51934968a77724614c02c1264b8f1fc7d394e13a
[INFO] running `Command { std: "docker" "start" "-a" "fd106f36102d288a71051f4f51934968a77724614c02c1264b8f1fc7d394e13a", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.67
[INFO] [stderr]    Compiling futures-core v0.3.28
[INFO] [stderr]    Compiling futures-channel v0.3.28
[INFO] [stderr]    Compiling futures-task v0.3.28
[INFO] [stderr]     Checking futures-sink v0.3.28
[INFO] [stderr]    Compiling futures-util v0.3.28
[INFO] [stderr]     Checking futures-io v0.3.28
[INFO] [stderr]     Checking memchr v2.6.3
[INFO] [stderr]    Compiling quote v1.0.33
[INFO] [stderr]    Compiling syn v2.0.37
[INFO] [stderr]    Compiling futures-macro v0.3.28
[INFO] [stderr]     Checking futures-executor v0.3.28
[INFO] [stderr]     Checking futures v0.3.28
[INFO] [stderr]     Checking async-test v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: denote infinite loops with `loop { ... }`
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     while true {
[INFO] [stdout]   |     ^^^^^^^^^^ help: use `loop`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(while_true)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: denote infinite loops with `loop { ... }`
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     while true {
[INFO] [stdout]   |     ^^^^^^^^^^ help: use `loop`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(while_true)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `poll`
[INFO] [stdout]  --> src/test.rs:1:47
[INFO] [stdout]   |
[INFO] [stdout] 1 | use futures::{future::{BoxFuture, FutureExt}, poll, task::{waker_ref, ArcWake}};
[INFO] [stdout]   |                                               ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `poll`
[INFO] [stdout]  --> src/test.rs:1:47
[INFO] [stdout]   |
[INFO] [stdout] 1 | use futures::{future::{BoxFuture, FutureExt}, poll, task::{waker_ref, ArcWake}};
[INFO] [stdout]   |                                               ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let mut a = Mutex::new(Some(0));
[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: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let mut a = Mutex::new(Some(0));
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[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 5.21s
[INFO] running `Command { std: "docker" "inspect" "fd106f36102d288a71051f4f51934968a77724614c02c1264b8f1fc7d394e13a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fd106f36102d288a71051f4f51934968a77724614c02c1264b8f1fc7d394e13a", kill_on_drop: false }`
[INFO] [stdout] fd106f36102d288a71051f4f51934968a77724614c02c1264b8f1fc7d394e13a