[INFO] cloning repository https://github.com/CMU-Blockchain-Group/rust-workshop-0
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/CMU-Blockchain-Group/rust-workshop-0" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCMU-Blockchain-Group%2Frust-workshop-0", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCMU-Blockchain-Group%2Frust-workshop-0'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 88e8e82df47bb6e2955ab850f906248baad9c8fe
[INFO] checking CMU-Blockchain-Group/rust-workshop-0 against try#ea2bf32540662c61547071aad6cf0851a0b02f58 for pr-96376
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCMU-Blockchain-Group%2Frust-workshop-0" "/workspace/builds/worker-88/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-88/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/CMU-Blockchain-Group/rust-workshop-0 on toolchain ea2bf32540662c61547071aad6cf0851a0b02f58
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ea2bf32540662c61547071aad6cf0851a0b02f58" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/CMU-Blockchain-Group/rust-workshop-0
[INFO] finished tweaking git repo https://github.com/CMU-Blockchain-Group/rust-workshop-0
[INFO] tweaked toml for git repo https://github.com/CMU-Blockchain-Group/rust-workshop-0 written to /workspace/builds/worker-88/source/Cargo.toml
[INFO] crate git repo https://github.com/CMU-Blockchain-Group/rust-workshop-0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ea2bf32540662c61547071aad6cf0851a0b02f58" "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-88/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+ea2bf32540662c61547071aad6cf0851a0b02f58" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d764781b341e5ae5f7784ee4a94d719c8ef90b7186a3b17e2b02e1ab8ab62531
[INFO] running `Command { std: "docker" "start" "-a" "d764781b341e5ae5f7784ee4a94d719c8ef90b7186a3b17e2b02e1ab8ab62531", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d764781b341e5ae5f7784ee4a94d719c8ef90b7186a3b17e2b02e1ab8ab62531", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d764781b341e5ae5f7784ee4a94d719c8ef90b7186a3b17e2b02e1ab8ab62531", kill_on_drop: false }`
[INFO] [stdout] d764781b341e5ae5f7784ee4a94d719c8ef90b7186a3b17e2b02e1ab8ab62531
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+ea2bf32540662c61547071aad6cf0851a0b02f58" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a4ad10f4bbb2d7fbce5fff458c5f5ed0f3898904a1340657d5907e6775ef843d
[INFO] running `Command { std: "docker" "start" "-a" "a4ad10f4bbb2d7fbce5fff458c5f5ed0f3898904a1340657d5907e6775ef843d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking rust-workshop-0 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `buf`
[INFO] [stdout]   --> src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let buf = string_to_mine.as_bytes();
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_buf`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]  --> src/exercises.rs:3:18
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn swap_two_ints(a: &mut i32, b: &mut i32) {
[INFO] [stdout]   |                  ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> src/exercises.rs:3:31
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn swap_two_ints(a: &mut i32, b: &mut i32) {
[INFO] [stdout]   |                               ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/exercises.rs:14:18
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn rect_overlaps(a: &Rectangle, b: &Rectangle) -> bool {
[INFO] [stdout]    |                  ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/exercises.rs:14:33
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn rect_overlaps(a: &Rectangle, b: &Rectangle) -> bool {
[INFO] [stdout]    |                                 ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `play`
[INFO] [stdout]   --> src/exercises.rs:27:17
[INFO] [stdout]    |
[INFO] [stdout] 27 | fn rps_weakness(play: RockPaperScissors) -> RockPaperScissors {
[INFO] [stdout]    |                 ^^^^ help: if this is intentional, prefix it with an underscore: `_play`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/exercises.rs:34:16
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn dot_product(a: &[i32], b: &[i32]) -> i32 {
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/exercises.rs:34:27
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn dot_product(a: &[i32], b: &[i32]) -> i32 {
[INFO] [stdout]    |                           ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]   --> src/exercises.rs:40:16
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn first_n_fib(n: usize) -> Vec<u32> {
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/exercises.rs:48:28
[INFO] [stdout]    |
[INFO] [stdout] 48 | fn recursive_binary_search(a: &[i32]) -> Option<usize> {
[INFO] [stdout]    |                            ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `strs`
[INFO] [stdout]   --> src/exercises.rs:55:28
[INFO] [stdout]    |
[INFO] [stdout] 55 | fn flatten_slice_of_slices(strs: &[&[&str]]) -> String {
[INFO] [stdout]    |                            ^^^^ help: if this is intentional, prefix it with an underscore: `_strs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `DIFFICULTY`
[INFO] [stdout]  --> src/main.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | const DIFFICULTY: usize = 4;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Rectangle`
[INFO] [stdout]  --> src/exercises.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct Rectangle {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `rect_overlaps`
[INFO] [stdout]   --> src/exercises.rs:14:4
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn rect_overlaps(a: &Rectangle, b: &Rectangle) -> bool {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `RockPaperScissors`
[INFO] [stdout]   --> src/exercises.rs:19:6
[INFO] [stdout]    |
[INFO] [stdout] 19 | enum RockPaperScissors {
[INFO] [stdout]    |      ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `rps_weakness`
[INFO] [stdout]   --> src/exercises.rs:27:4
[INFO] [stdout]    |
[INFO] [stdout] 27 | fn rps_weakness(play: RockPaperScissors) -> RockPaperScissors {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `dot_product`
[INFO] [stdout]   --> src/exercises.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn dot_product(a: &[i32], b: &[i32]) -> i32 {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `first_n_fib`
[INFO] [stdout]   --> src/exercises.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn first_n_fib(n: usize) -> Vec<u32> {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `recursive_binary_search`
[INFO] [stdout]   --> src/exercises.rs:48:4
[INFO] [stdout]    |
[INFO] [stdout] 48 | fn recursive_binary_search(a: &[i32]) -> Option<usize> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `flatten_slice_of_slices`
[INFO] [stdout]   --> src/exercises.rs:55:4
[INFO] [stdout]    |
[INFO] [stdout] 55 | fn flatten_slice_of_slices(strs: &[&[&str]]) -> String {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `buf`
[INFO] [stdout]   --> src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let buf = string_to_mine.as_bytes();
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_buf`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]  --> src/exercises.rs:3:18
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn swap_two_ints(a: &mut i32, b: &mut i32) {
[INFO] [stdout]   |                  ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> src/exercises.rs:3:31
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn swap_two_ints(a: &mut i32, b: &mut i32) {
[INFO] [stdout]   |                               ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/exercises.rs:14:18
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn rect_overlaps(a: &Rectangle, b: &Rectangle) -> bool {
[INFO] [stdout]    |                  ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/exercises.rs:14:33
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn rect_overlaps(a: &Rectangle, b: &Rectangle) -> bool {
[INFO] [stdout]    |                                 ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `play`
[INFO] [stdout]   --> src/exercises.rs:27:17
[INFO] [stdout]    |
[INFO] [stdout] 27 | fn rps_weakness(play: RockPaperScissors) -> RockPaperScissors {
[INFO] [stdout]    |                 ^^^^ help: if this is intentional, prefix it with an underscore: `_play`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/exercises.rs:34:16
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn dot_product(a: &[i32], b: &[i32]) -> i32 {
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/exercises.rs:34:27
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn dot_product(a: &[i32], b: &[i32]) -> i32 {
[INFO] [stdout]    |                           ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]   --> src/exercises.rs:40:16
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn first_n_fib(n: usize) -> Vec<u32> {
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/exercises.rs:48:28
[INFO] [stdout]    |
[INFO] [stdout] 48 | fn recursive_binary_search(a: &[i32]) -> Option<usize> {
[INFO] [stdout]    |                            ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `strs`
[INFO] [stdout]   --> src/exercises.rs:55:28
[INFO] [stdout]    |
[INFO] [stdout] 55 | fn flatten_slice_of_slices(strs: &[&[&str]]) -> String {
[INFO] [stdout]    |                            ^^^^ help: if this is intentional, prefix it with an underscore: `_strs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `DIFFICULTY`
[INFO] [stdout]  --> src/main.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | const DIFFICULTY: usize = 4;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `swap_two_ints`
[INFO] [stdout]  --> src/exercises.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn swap_two_ints(a: &mut i32, b: &mut i32) {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Rectangle`
[INFO] [stdout]  --> src/exercises.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct Rectangle {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `rect_overlaps`
[INFO] [stdout]   --> src/exercises.rs:14:4
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn rect_overlaps(a: &Rectangle, b: &Rectangle) -> bool {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `RockPaperScissors`
[INFO] [stdout]   --> src/exercises.rs:19:6
[INFO] [stdout]    |
[INFO] [stdout] 19 | enum RockPaperScissors {
[INFO] [stdout]    |      ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `rps_weakness`
[INFO] [stdout]   --> src/exercises.rs:27:4
[INFO] [stdout]    |
[INFO] [stdout] 27 | fn rps_weakness(play: RockPaperScissors) -> RockPaperScissors {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `dot_product`
[INFO] [stdout]   --> src/exercises.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn dot_product(a: &[i32], b: &[i32]) -> i32 {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `first_n_fib`
[INFO] [stdout]   --> src/exercises.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn first_n_fib(n: usize) -> Vec<u32> {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `recursive_binary_search`
[INFO] [stdout]   --> src/exercises.rs:48:4
[INFO] [stdout]    |
[INFO] [stdout] 48 | fn recursive_binary_search(a: &[i32]) -> Option<usize> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `flatten_slice_of_slices`
[INFO] [stdout]   --> src/exercises.rs:55:4
[INFO] [stdout]    |
[INFO] [stdout] 55 | fn flatten_slice_of_slices(strs: &[&[&str]]) -> String {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 20 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 21 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.44s
[INFO] running `Command { std: "docker" "inspect" "a4ad10f4bbb2d7fbce5fff458c5f5ed0f3898904a1340657d5907e6775ef843d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a4ad10f4bbb2d7fbce5fff458c5f5ed0f3898904a1340657d5907e6775ef843d", kill_on_drop: false }`
[INFO] [stdout] a4ad10f4bbb2d7fbce5fff458c5f5ed0f3898904a1340657d5907e6775ef843d