[INFO] fetching crate sequencetree 0.1.4...
[INFO] checking sequencetree-0.1.4 against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] extracting crate sequencetree 0.1.4 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate sequencetree 0.1.4 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 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-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "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-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/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] 7029c6b547f2698a9ddce0f5499082e30cd8c208b2cd4a3cc58b90f8ff7b7ae5
[INFO] running `Command { std: "docker" "start" "-a" "7029c6b547f2698a9ddce0f5499082e30cd8c208b2cd4a3cc58b90f8ff7b7ae5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7029c6b547f2698a9ddce0f5499082e30cd8c208b2cd4a3cc58b90f8ff7b7ae5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7029c6b547f2698a9ddce0f5499082e30cd8c208b2cd4a3cc58b90f8ff7b7ae5", kill_on_drop: false }`
[INFO] [stdout] 7029c6b547f2698a9ddce0f5499082e30cd8c208b2cd4a3cc58b90f8ff7b7ae5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/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] 92da7a1389f129cc76e4c7078c41bb5666a8d12ae8218155b12544bbdc6a693a
[INFO] running `Command { std: "docker" "start" "-a" "92da7a1389f129cc76e4c7078c41bb5666a8d12ae8218155b12544bbdc6a693a", 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] [stderr]     Checking getrandom v0.1.16
[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: 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] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[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: 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:131:17
[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 2.84s
[INFO] running `Command { std: "docker" "inspect" "92da7a1389f129cc76e4c7078c41bb5666a8d12ae8218155b12544bbdc6a693a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "92da7a1389f129cc76e4c7078c41bb5666a8d12ae8218155b12544bbdc6a693a", kill_on_drop: false }`
[INFO] [stdout] 92da7a1389f129cc76e4c7078c41bb5666a8d12ae8218155b12544bbdc6a693a