[INFO] cloning repository https://github.com/SyedHzf/Rusting
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/SyedHzf/Rusting" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSyedHzf%2FRusting", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSyedHzf%2FRusting'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a5e4e7eb14bd82ab1429aa9c4210bc208bbc3e48
[INFO] checking SyedHzf/Rusting against try#84addd32a13fa2d3f62fe5d99031611147b7fb13 for pr-147565
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSyedHzf%2FRusting" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/SyedHzf/Rusting
[INFO] finished tweaking git repo https://github.com/SyedHzf/Rusting
[INFO] tweaked toml for git repo https://github.com/SyedHzf/Rusting written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/SyedHzf/Rusting on toolchain 84addd32a13fa2d3f62fe5d99031611147b7fb13
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+84addd32a13fa2d3f62fe5d99031611147b7fb13" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/SyedHzf/Rusting 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" "+84addd32a13fa2d3f62fe5d99031611147b7fb13" "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
[ERROR] error running command: no output for 300 seconds
[INFO] checking SyedHzf/Rusting against try#84addd32a13fa2d3f62fe5d99031611147b7fb13 for pr-147565
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSyedHzf%2FRusting" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/SyedHzf/Rusting
[INFO] finished tweaking git repo https://github.com/SyedHzf/Rusting
[INFO] tweaked toml for git repo https://github.com/SyedHzf/Rusting written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/SyedHzf/Rusting on toolchain 84addd32a13fa2d3f62fe5d99031611147b7fb13
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+84addd32a13fa2d3f62fe5d99031611147b7fb13" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/SyedHzf/Rusting 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" "+84addd32a13fa2d3f62fe5d99031611147b7fb13" "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-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+84addd32a13fa2d3f62fe5d99031611147b7fb13" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a9cd0e0121c187207c7f45b461130b81c8d92ebf7194cd2779371c0391d02730
[INFO] running `Command { std: "docker" "start" "-a" "a9cd0e0121c187207c7f45b461130b81c8d92ebf7194cd2779371c0391d02730", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a9cd0e0121c187207c7f45b461130b81c8d92ebf7194cd2779371c0391d02730", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a9cd0e0121c187207c7f45b461130b81c8d92ebf7194cd2779371c0391d02730", kill_on_drop: false }`
[INFO] [stdout] a9cd0e0121c187207c7f45b461130b81c8d92ebf7194cd2779371c0391d02730
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+84addd32a13fa2d3f62fe5d99031611147b7fb13" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] da7c041e8574e3fe4d6f0259e8d35e1e6a7a73de42ffaa58573bbcf2eace7a3f
[INFO] running `Command { std: "docker" "start" "-a" "da7c041e8574e3fe4d6f0259e8d35e1e6a7a73de42ffaa58573bbcf2eace7a3f", kill_on_drop: false }`
[INFO] [stderr]     Checking hello_cargo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/Ref_count.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let c = Node(6,Rc::clone(&a));
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/Ref_count.rs:17:13
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let b = Node(5,Rc::clone(&a));
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/Ref_count.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let c = Node(6,Rc::clone(&a));
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/Ref_count.rs:17:13
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let b = Node(5,Rc::clone(&a));
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> src/Ref_count.rs:3:10
[INFO] [stdout]   |
[INFO] [stdout] 3 |     Node(i32,Rc<List>),
[INFO] [stdout]   |     ---- ^^^ ^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 3 -     Node(i32,Rc<List>),
[INFO] [stdout] 3 +     Node((),()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> src/Ref_count.rs:3:10
[INFO] [stdout]   |
[INFO] [stdout] 3 |     Node(i32,Rc<List>),
[INFO] [stdout]   |     ---- ^^^ ^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 3 -     Node(i32,Rc<List>),
[INFO] [stdout] 3 +     Node((),()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `Ref_count` should have a snake case name
[INFO] [stdout]   --> src/main.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 | mod Ref_count;
[INFO] [stdout]    |     ^^^^^^^^^ help: convert the identifier to snake case: `ref_count`
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/main.rs:1:9
[INFO] [stdout]    |
[INFO] [stdout]  1 | #![warn(non_snake_case)]
[INFO] [stdout]    |         ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `Ref_count` should have a snake case name
[INFO] [stdout]   --> src/main.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 | mod Ref_count;
[INFO] [stdout]    |     ^^^^^^^^^ help: convert the identifier to snake case: `ref_count`
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/main.rs:1:9
[INFO] [stdout]    |
[INFO] [stdout]  1 | #![warn(non_snake_case)]
[INFO] [stdout]    |         ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.06s
[INFO] running `Command { std: "docker" "inspect" "da7c041e8574e3fe4d6f0259e8d35e1e6a7a73de42ffaa58573bbcf2eace7a3f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da7c041e8574e3fe4d6f0259e8d35e1e6a7a73de42ffaa58573bbcf2eace7a3f", kill_on_drop: false }`
[INFO] [stdout] da7c041e8574e3fe4d6f0259e8d35e1e6a7a73de42ffaa58573bbcf2eace7a3f