[INFO] cloning repository https://github.com/raiker/persistent-rope
[INFO] running `"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"`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fraiker%2Fpersistent-rope'...
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 7f638488c32998e1683a0a3ba8de4846c9a5dee7
[INFO] checking raiker/persistent-rope against try#ea663bba38739867a4b75ac820991b4f5d093c3b for pr-62262-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fraiker%2Fpersistent-rope" "/workspace/builds/worker-10/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-10/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/raiker/persistent-rope on toolchain ea663bba38739867a4b75ac820991b4f5d093c3b
[INFO] running `"/workspace/cargo-home/bin/cargo" "+ea663bba38739867a4b75ac820991b4f5d093c3b" "read-manifest" "--manifest-path" "Cargo.toml"`
[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-10/source/Cargo.toml
[INFO] crate git repo https://github.com/raiker/persistent-rope already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+ea663bba38739867a4b75ac820991b4f5d093c3b" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+ea663bba38739867a4b75ac820991b4f5d093c3b" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 6ee7a92e931d6f15529cb2a68ef457dec4425ee4647855c00b85f93d01a04dbe
[INFO] running `"docker" "start" "-a" "6ee7a92e931d6f15529cb2a68ef457dec4425ee4647855c00b85f93d01a04dbe"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking persistent-rope v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused variable: `parent`
[INFO] [stderr]    --> src/main.rs:141:69
[INFO] [stderr]     |
[INFO] [stderr] 141 |     fn rec_insert(key: K, val: V, current: &Rc<Option<TreeNode<K,V>>>, parent: Option<&Rc<Option<TreeNode<K,V>>>>) -> InsertionResultRecursion<K,V>{
[INFO] [stderr]     |                                                                        ^^^^^^ help: consider prefixing with an underscore: `_parent`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `RcSliceableString`
[INFO] [stderr]  --> src/rcstr.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | pub struct RcSliceableString {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/rcstr.rs:10:2
[INFO] [stderr]    |
[INFO] [stderr] 10 |     pub fn new(s: String) -> RcSliceableString {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `slice`
[INFO] [stderr]   --> src/rcstr.rs:19:2
[INFO] [stderr]    |
[INFO] [stderr] 19 |     pub fn slice(&self, start: usize, len: usize) -> RcSliceableString {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `as_str`
[INFO] [stderr]   --> src/rcstr.rs:34:2
[INFO] [stderr]    |
[INFO] [stderr] 34 |     pub fn as_str(&self) -> &str {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `parent`
[INFO] [stderr]    --> src/main.rs:141:69
[INFO] [stderr]     |
[INFO] [stderr] 141 |     fn rec_insert(key: K, val: V, current: &Rc<Option<TreeNode<K,V>>>, parent: Option<&Rc<Option<TreeNode<K,V>>>>) -> InsertionResultRecursion<K,V>{
[INFO] [stderr]     |                                                                        ^^^^^^ help: consider prefixing with an underscore: `_parent`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.03s
[INFO] running `"docker" "inspect" "6ee7a92e931d6f15529cb2a68ef457dec4425ee4647855c00b85f93d01a04dbe"`
[INFO] running `"docker" "rm" "-f" "6ee7a92e931d6f15529cb2a68ef457dec4425ee4647855c00b85f93d01a04dbe"`
[INFO] [stdout] 6ee7a92e931d6f15529cb2a68ef457dec4425ee4647855c00b85f93d01a04dbe