[INFO] cloning repository https://github.com/modulitos/CtCI-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/modulitos/CtCI-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2FCtCI-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2FCtCI-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8bbaa49c3eca43a77cf1a2cea1b6f98071ad2c78
[INFO] checking modulitos/CtCI-rust against beta-2020-07-24 for pr-75494-beta
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2FCtCI-rust" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/modulitos/CtCI-rust on toolchain beta-2020-07-24
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/modulitos/CtCI-rust
[INFO] finished tweaking git repo https://github.com/modulitos/CtCI-rust
[INFO] tweaked toml for git repo https://github.com/modulitos/CtCI-rust written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/modulitos/CtCI-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "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] f9e8cfb9a4318ac6d3a7715f20f1d81ea2cfb3098b31a15b7f61229695382ccd
[INFO] running `Command { std: "docker" "start" "-a" "f9e8cfb9a4318ac6d3a7715f20f1d81ea2cfb3098b31a15b7f61229695382ccd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f9e8cfb9a4318ac6d3a7715f20f1d81ea2cfb3098b31a15b7f61229695382ccd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f9e8cfb9a4318ac6d3a7715f20f1d81ea2cfb3098b31a15b7f61229695382ccd", kill_on_drop: false }`
[INFO] [stdout] f9e8cfb9a4318ac6d3a7715f20f1d81ea2cfb3098b31a15b7f61229695382ccd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 503555435ccb672a7abe06015e50f99293cb89b9bb1cbe83e9bbbf85bc3b77b0
[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" "503555435ccb672a7abe06015e50f99293cb89b9bb1cbe83e9bbbf85bc3b77b0", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.60
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]     Checking cfg-if v0.1.9
[INFO] [stderr]    Compiling lazy_static v1.3.0
[INFO] [stderr]     Checking ppv-lite86 v0.2.5
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling regex-syntax v0.6.12
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]     Checking c2-chacha v0.2.2
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling aho-corasick v0.7.6
[INFO] [stderr]     Checking getrandom v0.1.7
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.2
[INFO] [stderr]    Compiling regex v1.3.1
[INFO] [stderr]    Compiling derive_more v0.15.0
[INFO] [stderr]     Checking rust-solutions v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/linked_list/second.rs:11:27
[INFO] [stdout]    |
[INFO] [stdout] 11 | pub type Link<T> = Option<(Box<Node<T>>)>;
[INFO] [stdout]    |                           ^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::List`
[INFO] [stdout]    --> src/linked_list/second.rs:167:9
[INFO] [stdout]     |
[INFO] [stdout] 167 |     use super::List;
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashSet`
[INFO] [stdout]  --> src/linked_list/third.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::collections::HashSet;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashSet`
[INFO] [stdout]  --> src/linked_list/fifth.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::collections::HashSet;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashSet`
[INFO] [stdout]  --> src/linked_list/refcell_singly.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::collections::HashSet;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> src/stack.rs:115:9
[INFO] [stdout]     |
[INFO] [stdout] 115 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> src/binary_search_tree.rs:124:9
[INFO] [stdout]     |
[INFO] [stdout] 124 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Ord`, `Ordering`
[INFO] [stdout]  --> src/graph.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::cmp::{Ord, Ordering};
[INFO] [stdout]   |                ^^^  ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> src/graph.rs:178:9
[INFO] [stdout]     |
[INFO] [stdout] 178 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> src/binary_tree.rs:43:9
[INFO] [stdout]    |
[INFO] [stdout] 43 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> src/binary_tree_refcell.rs:51:9
[INFO] [stdout]    |
[INFO] [stdout] 51 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> src/binary_search_tree_refcell.rs:128:9
[INFO] [stdout]     |
[INFO] [stdout] 128 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/linked_list/second.rs:11:27
[INFO] [stdout]    |
[INFO] [stdout] 11 | pub type Link<T> = Option<(Box<Node<T>>)>;
[INFO] [stdout]    |                           ^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashSet`
[INFO] [stdout]  --> src/linked_list/third.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::collections::HashSet;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashSet`
[INFO] [stdout]  --> src/linked_list/fifth.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::collections::HashSet;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Ord`, `Ordering`
[INFO] [stdout]  --> src/graph.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::cmp::{Ord, Ordering};
[INFO] [stdout]   |                ^^^  ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/linked_list/second.rs:67:12
[INFO] [stdout]    |
[INFO] [stdout] 67 |     pub fn new() -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `into_iter`
[INFO] [stdout]   --> src/linked_list/second.rs:71:12
[INFO] [stdout]    |
[INFO] [stdout] 71 |     pub fn into_iter(self) -> IntoIter<T> {
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `iter`
[INFO] [stdout]   --> src/linked_list/second.rs:76:12
[INFO] [stdout]    |
[INFO] [stdout] 76 |     pub fn iter(&self) -> Iter<T> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `iter_mut`
[INFO] [stdout]   --> src/linked_list/second.rs:84:12
[INFO] [stdout]    |
[INFO] [stdout] 84 |     pub fn iter_mut(&mut self) -> IterMut<'_, T> {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `push`
[INFO] [stdout]   --> src/linked_list/second.rs:90:12
[INFO] [stdout]    |
[INFO] [stdout] 90 |     pub fn push(&mut self, elem: T) {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `peek`
[INFO] [stdout]    --> src/linked_list/second.rs:119:12
[INFO] [stdout]     |
[INFO] [stdout] 119 |     pub fn peek(&self) -> Option<&T> {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `peek_mut`
[INFO] [stdout]    --> src/linked_list/second.rs:123:12
[INFO] [stdout]     |
[INFO] [stdout] 123 |     pub fn peek_mut(&mut self) -> Option<&mut T> {
[INFO] [stdout]     |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/linked_list/third.rs:21:12
[INFO] [stdout]    |
[INFO] [stdout] 21 |     pub fn new() -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `append`
[INFO] [stdout]   --> src/linked_list/third.rs:25:12
[INFO] [stdout]    |
[INFO] [stdout] 25 |     pub fn append(&mut self, elem: T) -> Self {
[INFO] [stdout]    |            ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `tail`
[INFO] [stdout]   --> src/linked_list/third.rs:35:12
[INFO] [stdout]    |
[INFO] [stdout] 35 |     pub fn tail(&self) -> Self {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `head`
[INFO] [stdout]   --> src/linked_list/third.rs:40:12
[INFO] [stdout]    |
[INFO] [stdout] 40 |     pub fn head(&self) -> Option<&T> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `iter`
[INFO] [stdout]    --> src/linked_list/third.rs:107:12
[INFO] [stdout]     |
[INFO] [stdout] 107 |     pub fn iter(&self) -> Iter<'_, T> {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/linked_list/fourth.rs:19:8
[INFO] [stdout]    |
[INFO] [stdout] 19 |     fn new(elem: T) -> Rc<RefCell<Self>> {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/linked_list/fourth.rs:29:12
[INFO] [stdout]    |
[INFO] [stdout] 29 |     pub fn new() -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `push_front`
[INFO] [stdout]   --> src/linked_list/fourth.rs:35:12
[INFO] [stdout]    |
[INFO] [stdout] 35 |     pub fn push_front(&mut self, elem: T) {
[INFO] [stdout]    |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `peek_front`
[INFO] [stdout]   --> src/linked_list/fourth.rs:76:12
[INFO] [stdout]    |
[INFO] [stdout] 76 |     pub fn peek_front(&self) -> Option<Ref<T>> {
[INFO] [stdout]    |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `prev`
[INFO] [stdout]   --> src/linked_list/brandon.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 25 |     prev: Option<NodeRef<T>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `tail`
[INFO] [stdout]   --> src/linked_list/brandon.rs:39:8
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn tail(node: &NodeRef<T>) -> Option<NodeRef<T>> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `remove`
[INFO] [stdout]   --> src/linked_list/brandon.rs:46:8
[INFO] [stdout]    |
[INFO] [stdout] 46 |     fn remove(&mut self) {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/linked_list/brandon.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 |     fn new() -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `append`
[INFO] [stdout]   --> src/linked_list/brandon.rs:68:8
[INFO] [stdout]    |
[INFO] [stdout] 68 |     fn append(&mut self, new_value: T) {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `tail`
[INFO] [stdout]   --> src/linked_list/brandon.rs:85:8
[INFO] [stdout]    |
[INFO] [stdout] 85 |     fn tail(&self) -> Option<NodeRef<T>> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `iter`
[INFO] [stdout]   --> src/linked_list/brandon.rs:96:8
[INFO] [stdout]    |
[INFO] [stdout] 96 |     fn iter(&self) -> Iter<T> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `list_has_duplicates`
[INFO] [stdout]    --> src/linked_list/brandon.rs:102:8
[INFO] [stdout]     |
[INFO] [stdout] 102 |     fn list_has_duplicates(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `remove_duplicates`
[INFO] [stdout]    --> src/linked_list/brandon.rs:117:8
[INFO] [stdout]     |
[INFO] [stdout] 117 |     fn remove_duplicates(&mut self) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `main`
[INFO] [stdout]    --> src/linked_list/brandon.rs:228:4
[INFO] [stdout]     |
[INFO] [stdout] 228 | fn main() {
[INFO] [stdout]     |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/linked_list/fifth.rs:24:12
[INFO] [stdout]    |
[INFO] [stdout] 24 |     pub fn new() -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `push`
[INFO] [stdout]   --> src/linked_list/fifth.rs:31:12
[INFO] [stdout]    |
[INFO] [stdout] 31 |     pub fn push(&mut self, elem: T) {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `pop`
[INFO] [stdout]   --> src/linked_list/fifth.rs:53:12
[INFO] [stdout]    |
[INFO] [stdout] 53 |     pub fn pop(&mut self) -> Option<T> {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 41 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `ch5_p6_conversion`
[INFO] [stdout]   --> src/bin/ch5-p6_conversion.rs:7:1
[INFO] [stdout]    |
[INFO] [stdout] 7  | / fn determine_bits_basic(mut n1: u16, mut n2: u16) -> u8 {
[INFO] [stdout] 8  | |     let mut bits = 0;
[INFO] [stdout] 9  | |     while n1 > 0 || n2 > 0 {
[INFO] [stdout] 10 | |         // println!("n1: {:b}", n1);
[INFO] [stdout] ...  |
[INFO] [stdout] 41 | |     assert_eq!(determine_bits(0b11101_u16, 0b01111_u16), 2);
[INFO] [stdout] 42 | | }
[INFO] [stdout]    | |_^ consider adding a `main` function to `src/bin/ch5-p6_conversion.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `RCBTreeNode as Node`
[INFO] [stdout]  --> src/bin/ch4-p8_first-common-ancestor.rs:6:33
[INFO] [stdout]   |
[INFO] [stdout] 6 | use cracking::{RCBTree as Tree, RCBTreeNode as Node, RCBinaryTree as BinaryTree};
[INFO] [stdout]   |                                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> src/bin/ch4-p8_first-common-ancestor.rs:104:9
[INFO] [stdout]     |
[INFO] [stdout] 104 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `ch4_p8_first_common_ancestor`
[INFO] [stdout]    --> src/bin/ch4-p8_first-common-ancestor.rs:6:1
[INFO] [stdout]     |
[INFO] [stdout] 6   | / use cracking::{RCBTree as Tree, RCBTreeNode as Node, RCBinaryTree as BinaryTree};
[INFO] [stdout] 7   | | use std::rc::Rc;
[INFO] [stdout] 8   | |
[INFO] [stdout] 9   | | trait FirstCommonAncestor<T> {
[INFO] [stdout] ...   |
[INFO] [stdout] 242 | |     }
[INFO] [stdout] 243 | | }
[INFO] [stdout]     | |_^ consider adding a `main` function to `src/bin/ch4-p8_first-common-ancestor.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust-solutions`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0601]: `main` function not found in crate `ch5_p5_debugger`
[INFO] [stdout]   --> src/bin/ch5-p5_debugger.rs:6:1
[INFO] [stdout]    |
[INFO] [stdout] 6  | / fn debugger(n: u8) -> bool {
[INFO] [stdout] 7  | |     (n & (n - 1)) == 0
[INFO] [stdout] 8  | | }
[INFO] [stdout] 9  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 20 | |     assert_eq!(debugger(0b01000000_u8), true);
[INFO] [stdout] 21 | | }
[INFO] [stdout]    | |_^ consider adding a `main` function to `src/bin/ch5-p5_debugger.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> src/bin/ch4-p6_successor.rs:82:9
[INFO] [stdout]    |
[INFO] [stdout] 82 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `ch4_p6_successor`
[INFO] [stdout]    --> src/bin/ch4-p6_successor.rs:9:1
[INFO] [stdout]     |
[INFO] [stdout] 9   | / use cracking::{RCBinarySearchTree as BinarySearchTree, RCTree as Tree};
[INFO] [stdout] 10  | | use std::rc::Rc;
[INFO] [stdout] 11  | |
[INFO] [stdout] 12  | | trait FindSuccessor<T> {
[INFO] [stdout] ...   |
[INFO] [stdout] 162 | |     }
[INFO] [stdout] 163 | | }
[INFO] [stdout]     | |_^ consider adding a `main` function to `src/bin/ch4-p6_successor.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `is_one_away`
[INFO] [stdout]  --> src/bin/ch1-p5_one-away.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn is_one_away(s1: &str, s2: &str) -> bool {
[INFO] [stdout]   |    ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_conversion_width_1`
[INFO] [stdout]   --> src/bin/ch5-p8_draw-line.rs:88:4
[INFO] [stdout]    |
[INFO] [stdout] 88 | fn test_conversion_width_1() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/stack.rs:153:13
[INFO] [stdout]     |
[INFO] [stdout] 153 |         let mut s: Stack<u64> = Stack::new();
[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: associated function is never used: `list_has_duplicates`
[INFO] [stdout]    --> src/linked_list/brandon.rs:102:8
[INFO] [stdout]     |
[INFO] [stdout] 102 |     fn list_has_duplicates(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `main`
[INFO] [stdout]    --> src/linked_list/brandon.rs:228:4
[INFO] [stdout]     |
[INFO] [stdout] 228 | fn main() {
[INFO] [stdout]     |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "503555435ccb672a7abe06015e50f99293cb89b9bb1cbe83e9bbbf85bc3b77b0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "503555435ccb672a7abe06015e50f99293cb89b9bb1cbe83e9bbbf85bc3b77b0", kill_on_drop: false }`
[INFO] [stdout] 503555435ccb672a7abe06015e50f99293cb89b9bb1cbe83e9bbbf85bc3b77b0
