[INFO] cloning repository https://github.com/undali/rustlings
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/undali/rustlings" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fundali%2Frustlings", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fundali%2Frustlings'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ba2ee0e2d85a3ad4ef1b3a3ba8f53e70ecb85a1e
[INFO] testing undali/rustlings against master#d98a5da813da67eb189387b8ccfb73cf481275d8+rustflags=-Copt-level=3 for pr-138759
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fundali%2Frustlings" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/undali/rustlings
[INFO] finished tweaking git repo https://github.com/undali/rustlings
[INFO] tweaked toml for git repo https://github.com/undali/rustlings written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/undali/rustlings on toolchain d98a5da813da67eb189387b8ccfb73cf481275d8
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d98a5da813da67eb189387b8ccfb73cf481275d8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/undali/rustlings 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" "+d98a5da813da67eb189387b8ccfb73cf481275d8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded serde_derive v1.0.129
[INFO] [stderr]   Downloaded notify v4.0.17
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[INFO] [stderr]   Downloaded serde v1.0.129
[INFO] [stderr]   Downloaded predicates-tree v1.0.3
[INFO] [stderr]   Downloaded terminal_size v0.1.17
[INFO] [stderr]   Downloaded assert_cmd v0.11.1
[INFO] [stderr]   Downloaded argh_shared v0.1.5
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[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d98a5da813da67eb189387b8ccfb73cf481275d8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 18ae934768979a5941064d6134c39dbdcca1b1bae80f06cec159a77ff88901ca
[INFO] running `Command { std: "docker" "start" "-a" "18ae934768979a5941064d6134c39dbdcca1b1bae80f06cec159a77ff88901ca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "18ae934768979a5941064d6134c39dbdcca1b1bae80f06cec159a77ff88901ca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "18ae934768979a5941064d6134c39dbdcca1b1bae80f06cec159a77ff88901ca", kill_on_drop: false }`
[INFO] [stdout] 18ae934768979a5941064d6134c39dbdcca1b1bae80f06cec159a77ff88901ca
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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 -Copt-level=3" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d98a5da813da67eb189387b8ccfb73cf481275d8" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 13d91e5acd8cc854e5fe615aaa1c1ec3da0f32bd625eaabf4496de449339d979
[INFO] running `Command { std: "docker" "start" "-a" "13d91e5acd8cc854e5fe615aaa1c1ec3da0f32bd625eaabf4496de449339d979", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.100
[INFO] [stderr]    Compiling proc-macro2 v1.0.28
[INFO] [stderr]    Compiling syn v1.0.75
[INFO] [stderr]    Compiling serde_derive v1.0.129
[INFO] [stderr]    Compiling serde v1.0.129
[INFO] [stderr]    Compiling portable-atomic v0.3.19
[INFO] [stderr]    Compiling lazycell v1.3.0
[INFO] [stderr]    Compiling argh_shared v0.1.5
[INFO] [stderr]    Compiling serde_json v1.0.81
[INFO] [stderr]    Compiling walkdir v2.3.2
[INFO] [stderr]    Compiling number_prefix v0.4.0
[INFO] [stderr]    Compiling home v0.5.3
[INFO] [stderr]    Compiling aho-corasick v0.7.18
[INFO] [stderr]    Compiling glob v0.3.0
[INFO] [stderr]    Compiling regex v1.5.5
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling net2 v0.2.37
[INFO] [stderr]    Compiling terminal_size v0.1.17
[INFO] [stderr]    Compiling inotify-sys v0.1.5
[INFO] [stderr]    Compiling filetime v0.2.15
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling inotify v0.7.1
[INFO] [stderr]    Compiling mio v0.6.23
[INFO] [stderr]    Compiling mio-extras v2.0.6
[INFO] [stderr]    Compiling notify v4.0.17
[INFO] [stderr]    Compiling console v0.15.0
[INFO] [stderr]    Compiling indicatif v0.17.3
[INFO] [stderr]    Compiling argh_derive v0.1.5
[INFO] [stderr]    Compiling argh v0.1.5
[INFO] [stderr]    Compiling toml v0.5.9
[INFO] [stderr]    Compiling rustlings v5.4.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `ProgressBar` and `ProgressStyle`
[INFO] [stdout]    --> src/main.rs:120:17
[INFO] [stdout]     |
[INFO] [stdout] 120 | use indicatif::{ProgressBar, ProgressStyle};
[INFO] [stdout]     |                 ^^^^^^^^^^^  ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]   --> src/verify.rs:67:5
[INFO] [stdout]    |
[INFO] [stdout] 51 |     std::process::exit(0);
[INFO] [stdout]    |     --------------------- any code following this expression is unreachable
[INFO] [stdout] ...
[INFO] [stdout] 67 |     let mut cnt = 0;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `total`
[INFO] [stdout]   --> src/verify.rs:18:24
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let (mut num_done, total) = progress;
[INFO] [stdout]    |                        ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `cnt`
[INFO] [stdout]   --> src/verify.rs:67:13
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let mut cnt = 0;
[INFO] [stdout]    |             ^^^ help: if this is intentional, prefix it with an underscore: `_cnt`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `compile_result`
[INFO] [stdout]   --> src/verify.rs:69:13
[INFO] [stdout]    |
[INFO] [stdout] 69 |         let compile_result = match exercise.mode {
[INFO] [stdout]    |             ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_compile_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `exercises`
[INFO] [stdout]   --> src/verify.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     exercises: impl IntoIterator<Item = &'a Exercise>,
[INFO] [stdout]    |     ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_exercises`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `verbose`
[INFO] [stdout]   --> src/verify.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     verbose: bool,
[INFO] [stdout]    |     ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_verbose`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/verify.rs:18:10
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let (mut num_done, total) = progress;
[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: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]    --> src/exercise.rs:110:20
[INFO] [stdout]     |
[INFO] [stdout] 110 |     pub fn compile(&self) -> Result<CompiledExercise, ExerciseOutput> {
[INFO] [stdout]     |                    ^^^^^            ---------------- the lifetime gets resolved as `'_`
[INFO] [stdout]     |                    |
[INFO] [stdout]     |                    this lifetime flows to the output
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]     |
[INFO] [stdout] 110 |     pub fn compile(&self) -> Result<CompiledExercise<'_>, ExerciseOutput> {
[INFO] [stdout]     |                                                     ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1m 03s
[INFO] running `Command { std: "docker" "inspect" "13d91e5acd8cc854e5fe615aaa1c1ec3da0f32bd625eaabf4496de449339d979", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "13d91e5acd8cc854e5fe615aaa1c1ec3da0f32bd625eaabf4496de449339d979", kill_on_drop: false }`
[INFO] [stdout] 13d91e5acd8cc854e5fe615aaa1c1ec3da0f32bd625eaabf4496de449339d979
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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 -Copt-level=3" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d98a5da813da67eb189387b8ccfb73cf481275d8" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 82faa698da30b5f41b599aaf7dc52892a5d3f13d6fb17190ef8786cb26ccfd2a
[INFO] running `Command { std: "docker" "start" "-a" "82faa698da30b5f41b599aaf7dc52892a5d3f13d6fb17190ef8786cb26ccfd2a", kill_on_drop: false }`
[INFO] [stderr]    Compiling escargot v0.4.0
[INFO] [stderr]    Compiling predicates-core v1.0.2
[INFO] [stderr]    Compiling difference v2.0.0
[INFO] [stderr]    Compiling normalize-line-endings v0.3.0
[INFO] [stderr]    Compiling treeline v0.1.0
[INFO] [stderr]    Compiling float-cmp v0.8.0
[INFO] [stdout] warning: unused imports: `ProgressBar` and `ProgressStyle`
[INFO] [stdout]    --> src/main.rs:120:17
[INFO] [stdout]     |
[INFO] [stdout] 120 | use indicatif::{ProgressBar, ProgressStyle};
[INFO] [stdout]     |                 ^^^^^^^^^^^  ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]   --> src/verify.rs:67:5
[INFO] [stdout]    |
[INFO] [stdout] 51 |     std::process::exit(0);
[INFO] [stdout]    |     --------------------- any code following this expression is unreachable
[INFO] [stdout] ...
[INFO] [stdout] 67 |     let mut cnt = 0;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `total`
[INFO] [stdout]   --> src/verify.rs:18:24
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let (mut num_done, total) = progress;
[INFO] [stdout]    |                        ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `cnt`
[INFO] [stdout]   --> src/verify.rs:67:13
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let mut cnt = 0;
[INFO] [stdout]    |             ^^^ help: if this is intentional, prefix it with an underscore: `_cnt`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `compile_result`
[INFO] [stdout]   --> src/verify.rs:69:13
[INFO] [stdout]    |
[INFO] [stdout] 69 |         let compile_result = match exercise.mode {
[INFO] [stdout]    |             ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_compile_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `exercises`
[INFO] [stdout]   --> src/verify.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     exercises: impl IntoIterator<Item = &'a Exercise>,
[INFO] [stdout]    |     ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_exercises`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `verbose`
[INFO] [stdout]   --> src/verify.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     verbose: bool,
[INFO] [stdout]    |     ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_verbose`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/verify.rs:18:10
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let (mut num_done, total) = progress;
[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: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]    --> src/exercise.rs:110:20
[INFO] [stdout]     |
[INFO] [stdout] 110 |     pub fn compile(&self) -> Result<CompiledExercise, ExerciseOutput> {
[INFO] [stdout]     |                    ^^^^^            ---------------- the lifetime gets resolved as `'_`
[INFO] [stdout]     |                    |
[INFO] [stdout]     |                    this lifetime flows to the output
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]     |
[INFO] [stdout] 110 |     pub fn compile(&self) -> Result<CompiledExercise<'_>, ExerciseOutput> {
[INFO] [stdout]     |                                                     ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling predicates-tree v1.0.3
[INFO] [stderr]    Compiling predicates v1.0.8
[INFO] [stderr]    Compiling assert_cmd v0.11.1
[INFO] [stderr]    Compiling rustlings v5.4.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `ProgressBar` and `ProgressStyle`
[INFO] [stdout]    --> src/main.rs:120:17
[INFO] [stdout]     |
[INFO] [stdout] 120 | use indicatif::{ProgressBar, ProgressStyle};
[INFO] [stdout]     |                 ^^^^^^^^^^^  ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]   --> src/verify.rs:67:5
[INFO] [stdout]    |
[INFO] [stdout] 51 |     std::process::exit(0);
[INFO] [stdout]    |     --------------------- any code following this expression is unreachable
[INFO] [stdout] ...
[INFO] [stdout] 67 |     let mut cnt = 0;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `total`
[INFO] [stdout]   --> src/verify.rs:18:24
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let (mut num_done, total) = progress;
[INFO] [stdout]    |                        ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `cnt`
[INFO] [stdout]   --> src/verify.rs:67:13
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let mut cnt = 0;
[INFO] [stdout]    |             ^^^ help: if this is intentional, prefix it with an underscore: `_cnt`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `compile_result`
[INFO] [stdout]   --> src/verify.rs:69:13
[INFO] [stdout]    |
[INFO] [stdout] 69 |         let compile_result = match exercise.mode {
[INFO] [stdout]    |             ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_compile_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `exercises`
[INFO] [stdout]   --> src/verify.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     exercises: impl IntoIterator<Item = &'a Exercise>,
[INFO] [stdout]    |     ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_exercises`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `verbose`
[INFO] [stdout]   --> src/verify.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     verbose: bool,
[INFO] [stdout]    |     ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_verbose`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/verify.rs:18:10
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let (mut num_done, total) = progress;
[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: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]    --> src/exercise.rs:110:20
[INFO] [stdout]     |
[INFO] [stdout] 110 |     pub fn compile(&self) -> Result<CompiledExercise, ExerciseOutput> {
[INFO] [stdout]     |                    ^^^^^            ---------------- the lifetime gets resolved as `'_`
[INFO] [stdout]     |                    |
[INFO] [stdout]     |                    this lifetime flows to the output
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]     |
[INFO] [stdout] 110 |     pub fn compile(&self) -> Result<CompiledExercise<'_>, ExerciseOutput> {
[INFO] [stdout]     |                                                     ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 8.78s
[INFO] running `Command { std: "docker" "inspect" "82faa698da30b5f41b599aaf7dc52892a5d3f13d6fb17190ef8786cb26ccfd2a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "82faa698da30b5f41b599aaf7dc52892a5d3f13d6fb17190ef8786cb26ccfd2a", kill_on_drop: false }`
[INFO] [stdout] 82faa698da30b5f41b599aaf7dc52892a5d3f13d6fb17190ef8786cb26ccfd2a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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 -Copt-level=3" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d98a5da813da67eb189387b8ccfb73cf481275d8" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] e84dd7592240211cd48302ba320d352d21dbc440a810f5f2f4bbf3e1d46a6b32
[INFO] running `Command { std: "docker" "start" "-a" "e84dd7592240211cd48302ba320d352d21dbc440a810f5f2f4bbf3e1d46a6b32", kill_on_drop: false }`
[INFO] [stderr] warning: unused imports: `ProgressBar` and `ProgressStyle`
[INFO] [stderr]    --> src/main.rs:120:17
[INFO] [stderr]     |
[INFO] [stderr] 120 | use indicatif::{ProgressBar, ProgressStyle};
[INFO] [stderr]     |                 ^^^^^^^^^^^  ^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unreachable statement
[INFO] [stderr]   --> src/verify.rs:67:5
[INFO] [stderr]    |
[INFO] [stderr] 51 |     std::process::exit(0);
[INFO] [stderr]    |     --------------------- any code following this expression is unreachable
[INFO] [stderr] ...
[INFO] [stderr] 67 |     let mut cnt = 0;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `total`
[INFO] [stderr]   --> src/verify.rs:18:24
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let (mut num_done, total) = progress;
[INFO] [stderr]    |                        ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `cnt`
[INFO] [stderr]   --> src/verify.rs:67:13
[INFO] [stderr]    |
[INFO] [stderr] 67 |     let mut cnt = 0;
[INFO] [stderr]    |             ^^^ help: if this is intentional, prefix it with an underscore: `_cnt`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `compile_result`
[INFO] [stderr]   --> src/verify.rs:69:13
[INFO] [stderr]    |
[INFO] [stderr] 69 |         let compile_result = match exercise.mode {
[INFO] [stderr]    |             ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_compile_result`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `exercises`
[INFO] [stderr]   --> src/verify.rs:14:5
[INFO] [stderr]    |
[INFO] [stderr] 14 |     exercises: impl IntoIterator<Item = &'a Exercise>,
[INFO] [stderr]    |     ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_exercises`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `verbose`
[INFO] [stderr]   --> src/verify.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 |     verbose: bool,
[INFO] [stderr]    |     ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_verbose`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/verify.rs:18:10
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let (mut num_done, total) = progress;
[INFO] [stderr]    |          ----^^^^^^^^
[INFO] [stderr]    |          |
[INFO] [stderr]    |          help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stderr]    --> src/exercise.rs:110:20
[INFO] [stderr]     |
[INFO] [stderr] 110 |     pub fn compile(&self) -> Result<CompiledExercise, ExerciseOutput> {
[INFO] [stderr]     |                    ^^^^^            ---------------- the lifetime gets resolved as `'_`
[INFO] [stderr]     |                    |
[INFO] [stderr]     |                    this lifetime flows to the output
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stderr] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stderr]     |
[INFO] [stderr] 110 |     pub fn compile(&self) -> Result<CompiledExercise<'_>, ExerciseOutput> {
[INFO] [stderr]     |                                                     ++++
[INFO] [stderr] 
[INFO] [stderr] warning: `rustlings` (bin "rustlings" test) generated 9 warnings (run `cargo fix --bin "rustlings" --tests` to apply 2 suggestions)
[INFO] [stderr] warning: `rustlings` (bin "rustlings") generated 9 warnings (9 duplicates)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.10s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/rustlings-c96beca5a7697a6c)
[INFO] [stdout] running 4 tests
[INFO] [stdout] test exercise::test::test_pending_state ... ok
[INFO] [stdout] test exercise::test::test_finished_exercise ... ok
[INFO] [stdout] test exercise::test::test_clean ... FAILED
[INFO] [stdout] test exercise::test::test_exercise_with_output ... FAILED
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- exercise::test::test_clean stdout ----
[INFO] [stdout] 
[INFO] [stdout] thread 'exercise::test::test_clean' panicked at src/exercise.rs:273:36:
[INFO] [stdout] called `Result::unwrap()` on an `Err` value: Os { code: 30, kind: ReadOnlyFilesystem, message: "Read-only file system" }
[INFO] [stdout] stack backtrace:
[INFO] [stdout]    0:     0x559e3dd49912 - std::backtrace_rs::backtrace::libunwind::trace::hd39b1f53d3cf9745
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
[INFO] [stdout]    1:     0x559e3dd49912 - std::backtrace_rs::backtrace::trace_unsynchronized::he91d9a75d4e3972b
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
[INFO] [stdout]    2:     0x559e3dd49912 - std::sys::backtrace::_print_fmt::hca46938f8c6e22cf
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:66:9
[INFO] [stdout]    3:     0x559e3dd49912 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::ha499add612cccf8e
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:39:26
[INFO] [stdout]    4:     0x559e3dd6f363 - core::fmt::rt::Argument::fmt::hd21145b75a833b7a
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/fmt/rt.rs:173:76
[INFO] [stdout]    5:     0x559e3dd6f363 - core::fmt::write::hb10c956f5235c8a4
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/fmt/mod.rs:1465:25
[INFO] [stdout]    6:     0x559e3dd46a33 - std::io::default_write_fmt::hdb7615052be2ba4d
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/io/mod.rs:639:11
[INFO] [stdout]    7:     0x559e3dd46a33 - std::io::Write::write_fmt::he1bcd251ec6e4153
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/io/mod.rs:1954:13
[INFO] [stdout]    8:     0x559e3dd49762 - std::sys::backtrace::BacktraceLock::print::hb47c770ef659fd10
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:42:9
[INFO] [stdout]    9:     0x559e3dd4af3c - std::panicking::default_hook::{{closure}}::hdda8afb9d457a22c
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:300:27
[INFO] [stdout]   10:     0x559e3dd4ad92 - std::panicking::default_hook::h7c46b44874fe5c9a
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:324:9
[INFO] [stdout]   11:     0x559e3dc9ef64 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h178a5fcedee41e2f
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1985:9
[INFO] [stdout]   12:     0x559e3dc9ef64 - test::test_main_with_exit_callback::{{closure}}::h951a41e0149d6d5d
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:145:21
[INFO] [stdout]   13:     0x559e3dd4ba1b - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h13602080f5b63276
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1985:9
[INFO] [stdout]   14:     0x559e3dd4ba1b - std::panicking::rust_panic_with_hook::ha6cb99ed099eb1c5
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:841:13
[INFO] [stdout]   15:     0x559e3dd4b6ea - std::panicking::begin_panic_handler::{{closure}}::he11808bc797ee921
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:706:13
[INFO] [stdout]   16:     0x559e3dd49e19 - std::sys::backtrace::__rust_end_short_backtrace::h9418807cb7346258
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:168:18
[INFO] [stdout]   17:     0x559e3dd4b37d - __rustc[18fb429eef004894]::rust_begin_unwind
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:697:5
[INFO] [stdout]   18:     0x559e3dd6deb0 - core::panicking::panic_fmt::hd890aeb12c3a3fc3
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/panicking.rs:75:14
[INFO] [stdout]   19:     0x559e3dd6e256 - core::result::unwrap_failed::h31c9775ec1a50121
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/result.rs:1761:5
[INFO] [stdout]   20:     0x559e3dc607f4 - core::result::Result<T,E>::unwrap::h634d57cb9153ed8a
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/result.rs:1167:23
[INFO] [stdout]   21:     0x559e3dc607f4 - rustlings::exercise::test::test_clean::h645375178a62e873
[INFO] [stdout]                                at /opt/rustwide/workdir/src/exercise.rs:273:36
[INFO] [stdout]   22:     0x559e3dc64149 - rustlings::exercise::test::test_clean::{{closure}}::hf86b41b581cba430
[INFO] [stdout]                                at /opt/rustwide/workdir/src/exercise.rs:272:20
[INFO] [stdout]   23:     0x559e3dc64149 - core::ops::function::FnOnce::call_once::h5c6a2b96449b5a31
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   24:     0x559e3dca46eb - core::ops::function::FnOnce::call_once::h2869fb5b0a2b0bdc
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   25:     0x559e3dca46eb - test::__rust_begin_short_backtrace::h7dd7142bd62fa711
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:648:18
[INFO] [stdout]   26:     0x559e3dca38de - test::run_test_in_process::{{closure}}::h43a753f038d36b3f
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:671:74
[INFO] [stdout]   27:     0x559e3dca38de - <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::h0ca95dd3e12d1e16
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/panic/unwind_safe.rs:272:9
[INFO] [stdout]   28:     0x559e3dca38de - std::panicking::catch_unwind::do_call::he308587d70ac34ba
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:589:40
[INFO] [stdout]   29:     0x559e3dca38de - std::panicking::catch_unwind::h30dcba31973e8fb0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:552:19
[INFO] [stdout]   30:     0x559e3dca38de - std::panic::catch_unwind::hfb68364e5621fbee
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panic.rs:359:14
[INFO] [stdout]   31:     0x559e3dca38de - test::run_test_in_process::hcdcc2977903b998a
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:671:27
[INFO] [stdout]   32:     0x559e3dca38de - test::run_test::{{closure}}::h544a6550958c5d14
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:592:43
[INFO] [stdout]   33:     0x559e3dc67454 - test::run_test::{{closure}}::hb172e48ebe2b92c7
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:622:41
[INFO] [stdout]   34:     0x559e3dc67454 - std::sys::backtrace::__rust_begin_short_backtrace::h7e79d8706638bea0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:152:18
[INFO] [stdout]   35:     0x559e3dc6ae2a - std::thread::Builder::spawn_unchecked_::{{closure}}::{{closure}}::hc4a275f1e71b8ab0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/thread/mod.rs:559:17
[INFO] [stdout]   36:     0x559e3dc6ae2a - <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::h01ed0d242df78cfd
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/panic/unwind_safe.rs:272:9
[INFO] [stdout]   37:     0x559e3dc6ae2a - std::panicking::catch_unwind::do_call::h052f373fb905fee0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:589:40
[INFO] [stdout]   38:     0x559e3dc6ae2a - std::panicking::catch_unwind::hb425d20c8ffb09c8
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:552:19
[INFO] [stdout]   39:     0x559e3dc6ae2a - std::panic::catch_unwind::ha0d5dfbf18fdeda5
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panic.rs:359:14
[INFO] [stdout]   40:     0x559e3dc6ae2a - std::thread::Builder::spawn_unchecked_::{{closure}}::hbe79182bd37949c7
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/thread/mod.rs:557:30
[INFO] [stdout]   41:     0x559e3dc6ae2a - core::ops::function::FnOnce::call_once{{vtable.shim}}::hc096c4a06972fde5
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   42:     0x559e3dd4e977 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h47377e27fb938a26
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1971:9
[INFO] [stdout]   43:     0x559e3dd4e977 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h72f1fe5d095abf57
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1971:9
[INFO] [stdout]   44:     0x559e3dd4e977 - std::sys::pal::unix::thread::Thread::new::thread_start::h0a4d8e1b9c0d38cf
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/pal/unix/thread.rs:97:17
[INFO] [stdout]   45:     0x7b3004c5baa4 - <unknown>
[INFO] [stdout]   46:     0x7b3004ce8a34 - clone
[INFO] [stdout]   47:                0x0 - <unknown>
[INFO] [stdout] 
[INFO] [stdout] ---- exercise::test::test_exercise_with_output stdout ----
[INFO] [stdout] 
[INFO] [stdout] thread 'exercise::test::test_exercise_with_output' panicked at src/exercise.rs:346:38:
[INFO] [stdout] called `Result::unwrap()` on an `Err` value: ExerciseOutput { stdout: "", stderr: "\u{1b}[0m\u{1b}[1m\u{1b}[38;5;9merror\u{1b}[0m\u{1b}[0m\u{1b}[1m: couldn't create a temp dir: Read-only file system (os error 30) at path \"/opt/rustwide/workdir/./rmeta3cPRDJ\"\u{1b}[0m\n\n\u{1b}[0m\u{1b}[1m\u{1b}[38;5;9merror\u{1b}[0m\u{1b}[0m\u{1b}[1m: aborting due to 1 previous error\u{1b}[0m\n\n" }
[INFO] [stdout] stack backtrace:
[INFO] [stdout]    0:     0x559e3dd49912 - std::backtrace_rs::backtrace::libunwind::trace::hd39b1f53d3cf9745
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
[INFO] [stdout]    1:     0x559e3dd49912 - std::backtrace_rs::backtrace::trace_unsynchronized::he91d9a75d4e3972b
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
[INFO] [stdout]    2:     0x559e3dd49912 - std::sys::backtrace::_print_fmt::hca46938f8c6e22cf
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:66:9
[INFO] [stdout]    3:     0x559e3dd49912 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::ha499add612cccf8e
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:39:26
[INFO] [stdout]    4:     0x559e3dd6f363 - core::fmt::rt::Argument::fmt::hd21145b75a833b7a
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/fmt/rt.rs:173:76
[INFO] [stdout]    5:     0x559e3dd6f363 - core::fmt::write::hb10c956f5235c8a4
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/fmt/mod.rs:1465:25
[INFO] [stdout]    6:     0x559e3dd46a33 - std::io::default_write_fmt::hdb7615052be2ba4d
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/io/mod.rs:639:11
[INFO] [stdout]    7:     0x559e3dd46a33 - std::io::Write::write_fmt::he1bcd251ec6e4153
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/io/mod.rs:1954:13
[INFO] [stdout]    8:     0x559e3dd49762 - std::sys::backtrace::BacktraceLock::print::hb47c770ef659fd10
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:42:9
[INFO] [stdout]    9:     0x559e3dd4af3c - std::panicking::default_hook::{{closure}}::hdda8afb9d457a22c
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:300:27
[INFO] [stdout]   10:     0x559e3dd4ad92 - std::panicking::default_hook::h7c46b44874fe5c9a
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:324:9
[INFO] [stdout]   11:     0x559e3dc9ef64 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h178a5fcedee41e2f
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1985:9
[INFO] [stdout]   12:     0x559e3dc9ef64 - test::test_main_with_exit_callback::{{closure}}::h951a41e0149d6d5d
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:145:21
[INFO] [stdout]   13:     0x559e3dd4ba1b - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h13602080f5b63276
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1985:9
[INFO] [stdout]   14:     0x559e3dd4ba1b - std::panicking::rust_panic_with_hook::ha6cb99ed099eb1c5
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:841:13
[INFO] [stdout]   15:     0x559e3dd4b6ea - std::panicking::begin_panic_handler::{{closure}}::he11808bc797ee921
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:706:13
[INFO] [stdout]   16:     0x559e3dd49e19 - std::sys::backtrace::__rust_end_short_backtrace::h9418807cb7346258
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:168:18
[INFO] [stdout]   17:     0x559e3dd4b37d - __rustc[18fb429eef004894]::rust_begin_unwind
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:697:5
[INFO] [stdout]   18:     0x559e3dd6deb0 - core::panicking::panic_fmt::hd890aeb12c3a3fc3
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/panicking.rs:75:14
[INFO] [stdout]   19:     0x559e3dd6e256 - core::result::unwrap_failed::h31c9775ec1a50121
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/result.rs:1761:5
[INFO] [stdout]   20:     0x559e3dc618af - core::result::Result<T,E>::unwrap::h4687f9a514352eda
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/result.rs:1167:23
[INFO] [stdout]   21:     0x559e3dc618af - rustlings::exercise::test::test_exercise_with_output::h9c4f40ea65cc152f
[INFO] [stdout]                                at /opt/rustwide/workdir/src/exercise.rs:346:38
[INFO] [stdout]   22:     0x559e3dc64129 - rustlings::exercise::test::test_exercise_with_output::{{closure}}::h575dacc590f38e20
[INFO] [stdout]                                at /opt/rustwide/workdir/src/exercise.rs:339:35
[INFO] [stdout]   23:     0x559e3dc64129 - core::ops::function::FnOnce::call_once::h413e0f09eee83a57
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   24:     0x559e3dca46eb - core::ops::function::FnOnce::call_once::h2869fb5b0a2b0bdc
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   25:     0x559e3dca46eb - test::__rust_begin_short_backtrace::h7dd7142bd62fa711
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:648:18
[INFO] [stdout]   26:     0x559e3dca38de - test::run_test_in_process::{{closure}}::h43a753f038d36b3f
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:671:74
[INFO] [stdout]   27:     0x559e3dca38de - <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::h0ca95dd3e12d1e16
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/panic/unwind_safe.rs:272:9
[INFO] [stdout]   28:     0x559e3dca38de - std::panicking::catch_unwind::do_call::he308587d70ac34ba
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:589:40
[INFO] [stdout]   29:     0x559e3dca38de - std::panicking::catch_unwind::h30dcba31973e8fb0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:552:19
[INFO] [stdout]   30:     0x559e3dca38de - std::panic::catch_unwind::hfb68364e5621fbee
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panic.rs:359:14
[INFO] [stdout]   31:     0x559e3dca38de - test::run_test_in_process::hcdcc2977903b998a
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:671:27
[INFO] [stdout]   32:     0x559e3dca38de - test::run_test::{{closure}}::h544a6550958c5d14
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:592:43
[INFO] [stdout]   33:     0x559e3dc67454 - test::run_test::{{closure}}::hb172e48ebe2b92c7
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/test/src/lib.rs:622:41
[INFO] [stdout]   34:     0x559e3dc67454 - std::sys::backtrace::__rust_begin_short_backtrace::h7e79d8706638bea0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/backtrace.rs:152:18
[INFO] [stdout]   35:     0x559e3dc6ae2a - std::thread::Builder::spawn_unchecked_::{{closure}}::{{closure}}::hc4a275f1e71b8ab0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/thread/mod.rs:559:17
[INFO] [stdout]   36:     0x559e3dc6ae2a - <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::h01ed0d242df78cfd
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/panic/unwind_safe.rs:272:9
[INFO] [stdout]   37:     0x559e3dc6ae2a - std::panicking::catch_unwind::do_call::h052f373fb905fee0
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:589:40
[INFO] [stdout]   38:     0x559e3dc6ae2a - std::panicking::catch_unwind::hb425d20c8ffb09c8
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panicking.rs:552:19
[INFO] [stdout]   39:     0x559e3dc6ae2a - std::panic::catch_unwind::ha0d5dfbf18fdeda5
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/panic.rs:359:14
[INFO] [stdout]   40:     0x559e3dc6ae2a - std::thread::Builder::spawn_unchecked_::{{closure}}::hbe79182bd37949c7
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/thread/mod.rs:557:30
[INFO] [stdout]   41:     0x559e3dc6ae2a - core::ops::function::FnOnce::call_once{{vtable.shim}}::hc096c4a06972fde5
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   42:     0x559e3dd4e977 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h47377e27fb938a26
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1971:9
[INFO] [stdout]   43:     0x559e3dd4e977 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h72f1fe5d095abf57
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/alloc/src/boxed.rs:1971:9
[INFO] [stdout]   44:     0x559e3dd4e977 - std::sys::pal::unix::thread::Thread::new::thread_start::h0a4d8e1b9c0d38cf
[INFO] [stdout]                                at /rustc/d98a5da813da67eb189387b8ccfb73cf481275d8/library/std/src/sys/pal/unix/thread.rs:97:17
[INFO] [stdout]   45:     0x7b3004c5baa4 - <unknown>
[INFO] [stdout]   46:     0x7b3004ce8a34 - clone
[INFO] [stdout]   47:                0x0 - <unknown>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     exercise::test::test_clean
[INFO] [stdout]     exercise::test::test_exercise_with_output
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 2 passed; 2 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.19s
[INFO] [stdout] 
[INFO] [stderr] error: test failed, to rerun pass `--bin rustlings`
[INFO] running `Command { std: "docker" "inspect" "e84dd7592240211cd48302ba320d352d21dbc440a810f5f2f4bbf3e1d46a6b32", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e84dd7592240211cd48302ba320d352d21dbc440a810f5f2f4bbf3e1d46a6b32", kill_on_drop: false }`
[INFO] [stdout] e84dd7592240211cd48302ba320d352d21dbc440a810f5f2f4bbf3e1d46a6b32
