[INFO] cloning repository https://github.com/ThinkingXuan/learning-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ThinkingXuan/learning-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FThinkingXuan%2Flearning-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FThinkingXuan%2Flearning-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] fef2402d68a58094ba0af2387fd2985c1d58ce44
[INFO] checking ThinkingXuan/learning-rust against try#4797991aa2efb6d658150f10425b3f3b5d10eceb for pr-143193
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FThinkingXuan%2Flearning-rust" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/ThinkingXuan/learning-rust
[INFO] finished tweaking git repo https://github.com/ThinkingXuan/learning-rust
[INFO] tweaked toml for git repo https://github.com/ThinkingXuan/learning-rust written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/ThinkingXuan/learning-rust on toolchain 4797991aa2efb6d658150f10425b3f3b5d10eceb
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4797991aa2efb6d658150f10425b3f3b5d10eceb" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/ThinkingXuan/learning-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4797991aa2efb6d658150f10425b3f3b5d10eceb" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+4797991aa2efb6d658150f10425b3f3b5d10eceb" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 32223ada66e5546d00989ad2e24e6608ea06c283c8ceccc3db04beac04afc4be
[INFO] running `Command { std: "docker" "start" "-a" "32223ada66e5546d00989ad2e24e6608ea06c283c8ceccc3db04beac04afc4be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "32223ada66e5546d00989ad2e24e6608ea06c283c8ceccc3db04beac04afc4be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32223ada66e5546d00989ad2e24e6608ea06c283c8ceccc3db04beac04afc4be", kill_on_drop: false }`
[INFO] [stdout] 32223ada66e5546d00989ad2e24e6608ea06c283c8ceccc3db04beac04afc4be
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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" "RUSTDOCFLAGS=--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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+4797991aa2efb6d658150f10425b3f3b5d10eceb" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a15cda6a07009ff2b5e078bfe17c84228cc3c44030a1c958c58bbb2873b287db
[INFO] running `Command { std: "docker" "start" "-a" "a15cda6a07009ff2b5e078bfe17c84228cc3c44030a1c958c58bbb2873b287db", kill_on_drop: false }`
[INFO] [stderr]     Checking test-rust-env v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]   --> src/main.rs:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let s3 = s2;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `T`
[INFO] [stdout]   --> src/main.rs:59:17
[INFO] [stdout]    |
[INFO] [stdout] 59 |     if let Some(T) = map.get(&123) {
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_T`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `k`
[INFO] [stdout]   --> src/main.rs:63:10
[INFO] [stdout]    |
[INFO] [stdout] 63 |     for &k in map.keys() {
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_k`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:80:9
[INFO] [stdout]    |
[INFO] [stdout] 80 |     let mut set: HashSet<i32> = nums.to_owned().into_iter().collect();
[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 `T` should have a snake case name
[INFO] [stdout]   --> src/main.rs:59:17
[INFO] [stdout]    |
[INFO] [stdout] 59 |     if let Some(T) = map.get(&123) {
[INFO] [stdout]    |                 ^ help: convert the identifier to snake case: `t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]   --> src/main.rs:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let s3 = s2;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `T`
[INFO] [stdout]   --> src/main.rs:59:17
[INFO] [stdout]    |
[INFO] [stdout] 59 |     if let Some(T) = map.get(&123) {
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_T`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `k`
[INFO] [stdout]   --> src/main.rs:63:10
[INFO] [stdout]    |
[INFO] [stdout] 63 |     for &k in map.keys() {
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_k`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:80:9
[INFO] [stdout]    |
[INFO] [stdout] 80 |     let mut set: HashSet<i32> = nums.to_owned().into_iter().collect();
[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 `T` should have a snake case name
[INFO] [stdout]   --> src/main.rs:59:17
[INFO] [stdout]    |
[INFO] [stdout] 59 |     if let Some(T) = map.get(&123) {
[INFO] [stdout]    |                 ^ help: convert the identifier to snake case: `t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.26s
[INFO] running `Command { std: "docker" "inspect" "a15cda6a07009ff2b5e078bfe17c84228cc3c44030a1c958c58bbb2873b287db", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a15cda6a07009ff2b5e078bfe17c84228cc3c44030a1c958c58bbb2873b287db", kill_on_drop: false }`
[INFO] [stdout] a15cda6a07009ff2b5e078bfe17c84228cc3c44030a1c958c58bbb2873b287db