[INFO] updating cached repository https://github.com/roynalnaruto/rs_merkle_tree
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 62324ec83f33a6413fa0dead25dcb1d18e6ff2da
[INFO] checking roynalnaruto/rs_merkle_tree against try#8a749131e7beb72f6edacefd2bdcbed3d67b2112 for pr-72331
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Froynalnaruto%2Frs_merkle_tree" "/workspace/builds/worker-7/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/roynalnaruto/rs_merkle_tree on toolchain 8a749131e7beb72f6edacefd2bdcbed3d67b2112
[INFO] running `"/workspace/cargo-home/bin/cargo" "+8a749131e7beb72f6edacefd2bdcbed3d67b2112" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/roynalnaruto/rs_merkle_tree
[INFO] finished tweaking git repo https://github.com/roynalnaruto/rs_merkle_tree
[INFO] tweaked toml for git repo https://github.com/roynalnaruto/rs_merkle_tree written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/roynalnaruto/rs_merkle_tree already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+8a749131e7beb72f6edacefd2bdcbed3d67b2112" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "+8a749131e7beb72f6edacefd2bdcbed3d67b2112" "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] 4123808f96ca5b0f32f3752bde0483e7d3c8ec563f5bf91c4db6575e41a8220c
[INFO] running `"docker" "start" "-a" "4123808f96ca5b0f32f3752bde0483e7d3c8ec563f5bf91c4db6575e41a8220c"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking rust-crypto v0.2.36
[INFO] [stderr]     Checking merkle_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: struct is never constructed: `MerkleTree`
[INFO] [stderr]   --> src/merkle_tree.rs:29:12
[INFO] [stderr]    |
[INFO] [stderr] 29 | pub struct MerkleTree<H, T>
[INFO] [stderr]    |            ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `root`
[INFO] [stderr]   --> src/merkle_tree.rs:42:8
[INFO] [stderr]    |
[INFO] [stderr] 42 |     fn root(&self) -> Result<&Node<T>, &'static str> {
[INFO] [stderr]    |        ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `count_leaves`
[INFO] [stderr]   --> src/merkle_tree.rs:49:8
[INFO] [stderr]    |
[INFO] [stderr] 49 |     fn count_leaves(&self) -> Result<usize, &'static str> {
[INFO] [stderr]    |        ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `add_leaves`
[INFO] [stderr]   --> src/merkle_tree.rs:59:8
[INFO] [stderr]    |
[INFO] [stderr] 59 |     fn add_leaves(&mut self, values: &mut Vec<T>) {
[INFO] [stderr]    |        ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `from_leaves`
[INFO] [stderr]   --> src/merkle_tree.rs:89:8
[INFO] [stderr]    |
[INFO] [stderr] 89 |     fn from_leaves(values: &mut Vec<T>, mut hasher: H) -> Result<Self, &'static str> {
[INFO] [stderr]    |        ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `build_parent_nodes`
[INFO] [stderr]    --> src/merkle_tree.rs:121:8
[INFO] [stderr]     |
[INFO] [stderr] 121 |     fn build_parent_nodes(children: &Vec<Node<T>>, mut hasher: &mut H) -> Vec<Node<T>> {
[INFO] [stderr]     |        ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `as_leaf`
[INFO] [stderr]    --> src/merkle_tree.rs:140:8
[INFO] [stderr]     |
[INFO] [stderr] 140 |     fn as_leaf(v: &T, hasher: &mut H) -> Node<T> {
[INFO] [stderr]     |        ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `as_internal`
[INFO] [stderr]    --> src/merkle_tree.rs:153:8
[INFO] [stderr]     |
[INFO] [stderr] 153 |     fn as_internal(left: &Node<T>, right: &Node<T>, hasher: &mut H) -> Node<T> {
[INFO] [stderr]     |        ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 8 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.64s
[INFO] running `"docker" "inspect" "4123808f96ca5b0f32f3752bde0483e7d3c8ec563f5bf91c4db6575e41a8220c"`
[INFO] running `"docker" "rm" "-f" "4123808f96ca5b0f32f3752bde0483e7d3c8ec563f5bf91c4db6575e41a8220c"`
[INFO] [stdout] 4123808f96ca5b0f32f3752bde0483e7d3c8ec563f5bf91c4db6575e41a8220c