[INFO] cloning repository https://github.com/raiker/persistent-rope
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/raiker/persistent-rope" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fraiker%2Fpersistent-rope", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fraiker%2Fpersistent-rope'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7f638488c32998e1683a0a3ba8de4846c9a5dee7
[INFO] checking raiker/persistent-rope against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fraiker%2Fpersistent-rope" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/raiker/persistent-rope on toolchain 45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/raiker/persistent-rope
[INFO] finished tweaking git repo https://github.com/raiker/persistent-rope
[INFO] tweaked toml for git repo https://github.com/raiker/persistent-rope written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/raiker/persistent-rope already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "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] 5f08dcc27319ba3a4854c037026f53c8b2cc7245968094053e1b68b46760b491
[INFO] running `Command { std: "docker" "start" "-a" "5f08dcc27319ba3a4854c037026f53c8b2cc7245968094053e1b68b46760b491", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5f08dcc27319ba3a4854c037026f53c8b2cc7245968094053e1b68b46760b491", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f08dcc27319ba3a4854c037026f53c8b2cc7245968094053e1b68b46760b491", kill_on_drop: false }`
[INFO] [stdout] 5f08dcc27319ba3a4854c037026f53c8b2cc7245968094053e1b68b46760b491
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] f50cfd0a52e39961d4ff66607d9035666a666764c9dcc830af2b50398d10c0a2
[INFO] running `Command { std: "docker" "start" "-a" "f50cfd0a52e39961d4ff66607d9035666a666764c9dcc830af2b50398d10c0a2", kill_on_drop: false }`
[INFO] [stderr]     Checking persistent-rope v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `parent`
[INFO] [stdout]    --> src/main.rs:141:69
[INFO] [stdout]     |
[INFO] [stdout] 141 | ... &Rc<Option<TreeNode<K,V>>>, parent: Option<&Rc<Option<TreeNode<K,V>>>>) -> InsertionResultRecursion<K,V>{
[INFO] [stdout]     |                                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_parent`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `RcSliceableString`
[INFO] [stdout]  --> src/rcstr.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub struct RcSliceableString {
[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: `new`
[INFO] [stdout]   --> src/rcstr.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     pub fn new(s: String) -> RcSliceableString {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `slice`
[INFO] [stdout]   --> src/rcstr.rs:19:9
[INFO] [stdout]    |
[INFO] [stdout] 19 |     pub fn slice(&self, start: usize, len: usize) -> RcSliceableString {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `as_str`
[INFO] [stdout]   --> src/rcstr.rs:34:9
[INFO] [stdout]    |
[INFO] [stdout] 34 |     pub fn as_str(&self) -> &str {
[INFO] [stdout]    |            ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `parent`
[INFO] [stdout]    --> src/main.rs:141:69
[INFO] [stdout]     |
[INFO] [stdout] 141 | ... &Rc<Option<TreeNode<K,V>>>, parent: Option<&Rc<Option<TreeNode<K,V>>>>) -> InsertionResultRecursion<K,V>{
[INFO] [stdout]     |                                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_parent`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` 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 0.51s
[INFO] running `Command { std: "docker" "inspect" "f50cfd0a52e39961d4ff66607d9035666a666764c9dcc830af2b50398d10c0a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f50cfd0a52e39961d4ff66607d9035666a666764c9dcc830af2b50398d10c0a2", kill_on_drop: false }`
[INFO] [stdout] f50cfd0a52e39961d4ff66607d9035666a666764c9dcc830af2b50398d10c0a2