[INFO] cloning repository https://github.com/123dou/learnRust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/123dou/learnRust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F123dou%2FlearnRust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F123dou%2FlearnRust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ec90636c8bfb766b5e8e89795b0658b9f15ebfa8
[INFO] building 123dou/learnRust against master#ad211ced81509462cdfe4c29ed10f97279a0acae for pr-135216
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F123dou%2FlearnRust" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/123dou/learnRust on toolchain ad211ced81509462cdfe4c29ed10f97279a0acae
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/123dou/learnRust
[INFO] finished tweaking git repo https://github.com/123dou/learnRust
[INFO] tweaked toml for git repo https://github.com/123dou/learnRust written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 41 packages to latest compatible versions
[INFO] [stderr]       Adding itertools v0.9.0 (available: v0.14.0)
[INFO] [stderr]       Adding rand v0.7.3 (available: v0.8.5)
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[INFO] [stderr]       Adding wasi v0.10.0+wasi-snapshot-preview1 (available: v0.10.2+wasi-snapshot-preview1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: profile `doc` is deprecated and has no effect
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded serde_derive v1.0.217
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[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9a4298ea4b49721d955bfac4508a3b4edbb2711a3d0a7adfc3280a4c5456d564
[INFO] running `Command { std: "docker" "start" "-a" "9a4298ea4b49721d955bfac4508a3b4edbb2711a3d0a7adfc3280a4c5456d564", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9a4298ea4b49721d955bfac4508a3b4edbb2711a3d0a7adfc3280a4c5456d564", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9a4298ea4b49721d955bfac4508a3b4edbb2711a3d0a7adfc3280a4c5456d564", kill_on_drop: false }`
[INFO] [stdout] 9a4298ea4b49721d955bfac4508a3b4edbb2711a3d0a7adfc3280a4c5456d564
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0b7485417e7d7b266291e6eac52cec5c734555ed6d6bbf8765ba5f63b2a2ca4a
[INFO] running `Command { std: "docker" "start" "-a" "0b7485417e7d7b266291e6eac52cec5c734555ed6d6bbf8765ba5f63b2a2ca4a", kill_on_drop: false }`
[INFO] [stderr] warning: profile `doc` is deprecated and has no effect
[INFO] [stderr]    Compiling proc-macro2 v1.0.92
[INFO] [stderr]    Compiling unicode-ident v1.0.14
[INFO] [stderr]    Compiling libc v0.2.169
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling byteorder v1.5.0
[INFO] [stderr]    Compiling serde v1.0.217
[INFO] [stderr]    Compiling gcc v0.3.55
[INFO] [stderr]    Compiling serde_json v1.0.135
[INFO] [stderr]    Compiling ryu v1.0.18
[INFO] [stderr]    Compiling itoa v1.0.14
[INFO] [stderr]    Compiling either v1.13.0
[INFO] [stderr]    Compiling rustc-serialize v0.3.25
[INFO] [stderr]    Compiling memchr v2.7.4
[INFO] [stderr]    Compiling itertools v0.9.0
[INFO] [stderr]    Compiling rust-crypto v0.2.36
[INFO] [stderr]    Compiling quote v1.0.38
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling time v0.1.45
[INFO] [stderr]    Compiling syn v2.0.95
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling zerocopy-derive v0.7.35
[INFO] [stderr]    Compiling serde_derive v1.0.217
[INFO] [stderr]    Compiling zerocopy v0.7.35
[INFO] [stderr]    Compiling ppv-lite86 v0.2.20
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling toml v0.5.11
[INFO] [stderr]    Compiling learn_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `crate::data_struct::link::Link`
[INFO] [stdout]  --> src/data_struct/link_test.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use crate::data_struct::link::Link;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/data_struct/mod.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | mod link_test;
[INFO] [stdout]   | ^^^^^^^^^^^^^^
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `toml::de::Error`
[INFO] [stdout]  --> src/learn_open_source/toml_demo.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use toml::de::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::VecDeque`
[INFO] [stdout]   --> src/leetcode/editor/cn/largest_rectangle_in_histogram_84.rs:36:5
[INFO] [stdout]    |
[INFO] [stdout] 36 | use std::collections::VecDeque;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::process::id`
[INFO] [stdout]   --> src/leetcode/editor/cn/largest_rectangle_in_histogram_84.rs:37:5
[INFO] [stdout]    |
[INFO] [stdout] 37 | use std::process::id;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::process::id`
[INFO] [stdout]   --> src/leetcode/editor/cn/redundant_connection_ii_685.rs:41:5
[INFO] [stdout]    |
[INFO] [stdout] 41 | use std::process::id;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::iter::FromIterator`
[INFO] [stdout]  --> src/leetcode/editor/cn/union_find.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::iter::FromIterator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `thread` and `time`
[INFO] [stdout]  --> src/sort/sort_test.rs:1:11
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{thread, time};
[INFO] [stdout]   |           ^^^^^^  ^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/sort/mod.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | mod sort_test;
[INFO] [stdout]   | ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::sort::sort`
[INFO] [stdout]  --> src/sort/sort_test.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use crate::sort::sort;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/sort/mod.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | mod sort_test;
[INFO] [stdout]   | ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::BinaryHeap`
[INFO] [stdout]  --> src/test_std/test_binary_heap.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::collections::BinaryHeap;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/mod.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | mod test_binary_heap;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `itertools::Itertools`
[INFO] [stdout]  --> src/test_std/test_binary_heap.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use itertools::Itertools;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/mod.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | mod test_binary_heap;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::VecDeque`
[INFO] [stdout]  --> src/test_std/test_string.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::collections::VecDeque;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/mod.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | mod test_string;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `channel`
[INFO] [stdout]  --> src/test_std/test_thread/proof_of_work_demo.rs:6:23
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::sync::mpsc::{channel, Sender};
[INFO] [stdout]   |                       ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/test_thread/mod.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | mod proof_of_work_demo;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `channel` and `sync_channel`
[INFO] [stdout]  --> src/test_std/test_thread/test_channel.rs:1:23
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::sync::mpsc::{channel, sync_channel};
[INFO] [stdout]   |                       ^^^^^^^  ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/test_thread/mod.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | mod test_channel;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread`
[INFO] [stdout]  --> src/test_std/test_thread/test_channel.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::thread;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/test_thread/mod.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | mod test_channel;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc` and `Mutex`
[INFO] [stdout]  --> src/test_std/test_thread/test_thread.rs:1:17
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::sync::{Arc, Mutex};
[INFO] [stdout]   |                 ^^^  ^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/test_thread/mod.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | mod test_thread;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashMap`
[INFO] [stdout]  --> src/test_std/test_trait/test_map.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::collections::HashMap;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/test_trait/mod.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | mod test_map;
[INFO] [stdout]   | ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `rand::prelude::SliceRandom`
[INFO] [stdout]  --> src/test_std/test_trait/test_partition.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::prelude::SliceRandom;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/test_trait/mod.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | mod test_partition;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `rand::thread_rng`
[INFO] [stdout]  --> src/test_std/test_trait/test_partition.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use rand::thread_rng;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/test_std/test_trait/mod.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | mod test_partition;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `entry_insert` has been stable since 1.83.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(entry_insert)]
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `drain_filter`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(drain_filter)]
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::borrow::Borrow`
[INFO] [stdout]   --> src/leetcode/editor/cn/easy/tree/symmetric_tree.rs:54:5
[INFO] [stdout]    |
[INFO] [stdout] 54 | use std::borrow::Borrow;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::borrow::Borrow`
[INFO] [stdout]   --> src/leetcode/editor/cn/easy/tree/validate_binary_search_tree.rs:54:5
[INFO] [stdout]    |
[INFO] [stdout] 54 | use std::borrow::Borrow;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `head_2` is never read
[INFO] [stdout]   --> src/leetcode/editor/cn/easy/List/palindrome_linked_list.rs:64:17
[INFO] [stdout]    |
[INFO] [stdout] 64 |         let mut head_2 = None;
[INFO] [stdout]    |                 ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `res` is never read
[INFO] [stdout]   --> src/leetcode/editor/cn/medium/other/evaluate_reverse_polish_notation.rs:91:17
[INFO] [stdout]    |
[INFO] [stdout] 91 |         let mut res = 0;
[INFO] [stdout]    |                 ^^^
[INFO] [stdout]    |
[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/leetcode/editor/cn/redundant_connection.rs:66:13
[INFO] [stdout]    |
[INFO] [stdout] 66 |         let mut graph = Graph::new(edges.len() + 1, &edges);
[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: value assigned to `min` is never read
[INFO] [stdout]   --> src/sort/sort.rs:25:13
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let mut min: i32 = i32::min_value();
[INFO] [stdout]    |             ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `to`
[INFO] [stdout]   --> src/test_std/test_trait/test_nll.rs:10:24
[INFO] [stdout]    |
[INFO] [stdout] 10 |         while let Some(to) = graph.get_mut("").unwrap_or(&mut BinaryHeap::new()).pop() {
[INFO] [stdout]    |                        ^^ help: if this is intentional, prefix it with an underscore: `_to`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `learn_rust` (lib) due to 1 previous error; 26 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "0b7485417e7d7b266291e6eac52cec5c734555ed6d6bbf8765ba5f63b2a2ca4a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0b7485417e7d7b266291e6eac52cec5c734555ed6d6bbf8765ba5f63b2a2ca4a", kill_on_drop: false }`
[INFO] [stdout] 0b7485417e7d7b266291e6eac52cec5c734555ed6d6bbf8765ba5f63b2a2ca4a
