[INFO] cloning repository https://github.com/loriopatrick/mem-help
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/loriopatrick/mem-help" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Floriopatrick%2Fmem-help", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Floriopatrick%2Fmem-help'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c78a24327a503add587f9dd0e72ec2d6bb465cb3
[INFO] checking loriopatrick/mem-help against try#f47dd4da3ae8c32c9e65d307bfe640b143e674df for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Floriopatrick%2Fmem-help" "/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/loriopatrick/mem-help on toolchain f47dd4da3ae8c32c9e65d307bfe640b143e674df
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/loriopatrick/mem-help
[INFO] finished tweaking git repo https://github.com/loriopatrick/mem-help
[INFO] tweaked toml for git repo https://github.com/loriopatrick/mem-help written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/loriopatrick/mem-help already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a5297f3d9273bb1900f2977f2b26ca2946e3277b7cd668883f1638b1f012da59
[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" "a5297f3d9273bb1900f2977f2b26ca2946e3277b7cd668883f1638b1f012da59", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a5297f3d9273bb1900f2977f2b26ca2946e3277b7cd668883f1638b1f012da59", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a5297f3d9273bb1900f2977f2b26ca2946e3277b7cd668883f1638b1f012da59", kill_on_drop: false }`
[INFO] [stdout] a5297f3d9273bb1900f2977f2b26ca2946e3277b7cd668883f1638b1f012da59
[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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 44dadf734d55a4ca953426814b26c2df5d93d2c6c1e7f7660b3ca811e763d2b2
[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" "44dadf734d55a4ca953426814b26c2df5d93d2c6c1e7f7660b3ca811e763d2b2", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.7
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]     Checking slab v0.4.2
[INFO] [stderr]     Checking futures-core v0.3.1
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]     Checking arc-swap v0.4.4
[INFO] [stderr]     Checking pin-project-lite v0.1.2
[INFO] [stderr]     Checking bytes v0.5.3
[INFO] [stderr]     Checking fnv v1.0.6
[INFO] [stderr]     Checking futures-channel v0.3.1
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking signal-hook-registry v1.2.0
[INFO] [stderr]     Checking num_cpus v1.11.1
[INFO] [stderr]     Checking mio v0.6.21
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]    Compiling proc-macro-hack v0.5.11
[INFO] [stderr]    Compiling tokio-macros v0.2.3
[INFO] [stderr]     Checking tokio v0.2.9
[INFO] [stderr]    Compiling futures-macro v0.3.1
[INFO] [stderr]     Checking futures-util v0.3.1
[INFO] [stderr]     Checking futures-executor v0.3.1
[INFO] [stderr]     Checking futures v0.3.1
[INFO] [stderr]     Checking mem-help v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `Sender`
[INFO] [stdout]  --> src/main.rs:5:44
[INFO] [stdout]   |
[INFO] [stdout] 5 | use tokio::sync::mpsc::{channel, Receiver, Sender};
[INFO] [stdout]   |                                            ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Sender`
[INFO] [stdout]  --> src/main.rs:5:44
[INFO] [stdout]   |
[INFO] [stdout] 5 | use tokio::sync::mpsc::{channel, Receiver, Sender};
[INFO] [stdout]   |                                            ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:51:17
[INFO] [stdout]    |
[INFO] [stdout] 51 |             for i in 0..500000 {
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:51:17
[INFO] [stdout]    |
[INFO] [stdout] 51 |             for i in 0..500000 {
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/main.rs:24:21
[INFO] [stdout]    |
[INFO] [stdout] 24 |                     std::mem::replace(&mut self.items, Vec::new());
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:52:17
[INFO] [stdout]    |
[INFO] [stdout] 52 |                 sender.send("Hello".to_string()).await;
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:57:13
[INFO] [stdout]    |
[INFO] [stdout] 57 |             sender.send("Hello".to_string()).await;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/main.rs:24:21
[INFO] [stdout]    |
[INFO] [stdout] 24 |                     std::mem::replace(&mut self.items, Vec::new());
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:52:17
[INFO] [stdout]    |
[INFO] [stdout] 52 |                 sender.send("Hello".to_string()).await;
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:57:13
[INFO] [stdout]    |
[INFO] [stdout] 57 |             sender.send("Hello".to_string()).await;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 38.44s
[INFO] running `Command { std: "docker" "inspect" "44dadf734d55a4ca953426814b26c2df5d93d2c6c1e7f7660b3ca811e763d2b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "44dadf734d55a4ca953426814b26c2df5d93d2c6c1e7f7660b3ca811e763d2b2", kill_on_drop: false }`
[INFO] [stdout] 44dadf734d55a4ca953426814b26c2df5d93d2c6c1e7f7660b3ca811e763d2b2