[INFO] fetching crate sequencetree 0.1.4...
[INFO] checking sequencetree-0.1.4 against master#39b841dfe36f90a7cd111e7f0c55f32594f6e578 for pr-77035
[INFO] extracting crate sequencetree 0.1.4 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate sequencetree 0.1.4 on toolchain 39b841dfe36f90a7cd111e7f0c55f32594f6e578
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39b841dfe36f90a7cd111e7f0c55f32594f6e578" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate sequencetree 0.1.4
[INFO] finished tweaking crates.io crate sequencetree 0.1.4
[INFO] tweaked toml for crates.io crate sequencetree 0.1.4 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39b841dfe36f90a7cd111e7f0c55f32594f6e578" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39b841dfe36f90a7cd111e7f0c55f32594f6e578" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: only one of `license` or `license-file` is necessary
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+39b841dfe36f90a7cd111e7f0c55f32594f6e578" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6e4e31875ae7050d34c205d69855003d7a30839e108d19a160f833c83d21a015
[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" "6e4e31875ae7050d34c205d69855003d7a30839e108d19a160f833c83d21a015", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6e4e31875ae7050d34c205d69855003d7a30839e108d19a160f833c83d21a015", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6e4e31875ae7050d34c205d69855003d7a30839e108d19a160f833c83d21a015", kill_on_drop: false }`
[INFO] [stdout] 6e4e31875ae7050d34c205d69855003d7a30839e108d19a160f833c83d21a015
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+39b841dfe36f90a7cd111e7f0c55f32594f6e578" "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] 99f4b417742c4a395ab14d1b35c89b44872b3be87564e241a83b4279637dc6a3
[INFO] running `Command { std: "docker" "start" "-a" "99f4b417742c4a395ab14d1b35c89b44872b3be87564e241a83b4279637dc6a3", kill_on_drop: false }`
[INFO] [stderr] warning: only one of `license` or `license-file` is necessary
[INFO] [stderr]     Checking sequencetree v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::fmt::Debug`
[INFO] [stdout]  --> src/binarysearchtree.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::fmt::Debug;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/binarysearchtree.rs:81:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     let mut val = match &mut n.val {
[INFO] [stdout]    |         ----^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/binarysearchtree.rs:104:9
[INFO] [stdout]     |
[INFO] [stdout] 104 |     let mut val = match &mut n.val {
[INFO] [stdout]     |         ----^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/sequencetree.rs:63:9
[INFO] [stdout]    |
[INFO] [stdout] 63 |     let mut n = create_node(key, i, val);
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt::Debug`
[INFO] [stdout]  --> src/binarysearchtree.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::fmt::Debug;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Duration`
[INFO] [stdout]   --> src/lib.rs:11:21
[INFO] [stdout]    |
[INFO] [stdout] 11 |     use std::time::{Duration, Instant};
[INFO] [stdout]    |                     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::binarysearchtree::BTree`
[INFO] [stdout]   --> src/lib.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     use crate::binarysearchtree::BTree;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `set_value`
[INFO] [stdout]   --> src/sequencetree.rs:30:8
[INFO] [stdout]    |
[INFO] [stdout] 30 |     fn set_value(&mut self, val: T) {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/lib.rs:123:13
[INFO] [stdout]     |
[INFO] [stdout] 123 |         for i in 0u64 .. TEST_SCALE {
[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: variable `key` is assigned to, but never used
[INFO] [stdout]    --> src/lib.rs:131:13
[INFO] [stdout]     |
[INFO] [stdout] 131 |         let mut key = String::new();
[INFO] [stdout]     |             ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_key` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `key` is never read
[INFO] [stdout]    --> src/lib.rs:133:13
[INFO] [stdout]     |
[INFO] [stdout] 133 |             key = gen_str(&mut rng);
[INFO] [stdout]     |             ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/binarysearchtree.rs:81:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     let mut val = match &mut n.val {
[INFO] [stdout]    |         ----^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/binarysearchtree.rs:104:9
[INFO] [stdout]     |
[INFO] [stdout] 104 |     let mut val = match &mut n.val {
[INFO] [stdout]     |         ----^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/sequencetree.rs:63:9
[INFO] [stdout]    |
[INFO] [stdout] 63 |     let mut n = create_node(key, i, val);
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `set_value`
[INFO] [stdout]   --> src/sequencetree.rs:30:8
[INFO] [stdout]    |
[INFO] [stdout] 30 |     fn set_value(&mut self, val: T) {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.27s
[INFO] running `Command { std: "docker" "inspect" "99f4b417742c4a395ab14d1b35c89b44872b3be87564e241a83b4279637dc6a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "99f4b417742c4a395ab14d1b35c89b44872b3be87564e241a83b4279637dc6a3", kill_on_drop: false }`
[INFO] [stdout] 99f4b417742c4a395ab14d1b35c89b44872b3be87564e241a83b4279637dc6a3