[INFO] cloning repository https://github.com/diegoxxc14/rust_basics
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/diegoxxc14/rust_basics" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdiegoxxc14%2Frust_basics", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdiegoxxc14%2Frust_basics'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7013103eedf3b905c12ce8494e16691fa3c9d353
[INFO] building diegoxxc14/rust_basics against master#44f415c1d617ebc7b931a243b7b321ef8a6ca47c for pr-142134-abi-ast-error
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdiegoxxc14%2Frust_basics" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/diegoxxc14/rust_basics on toolchain 44f415c1d617ebc7b931a243b7b321ef8a6ca47c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/diegoxxc14/rust_basics
[INFO] finished tweaking git repo https://github.com/diegoxxc14/rust_basics
[INFO] tweaked toml for git repo https://github.com/diegoxxc14/rust_basics written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/diegoxxc14/rust_basics 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" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "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-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:eea15d5475069c3ef791f10c2c6b5af2ee421ef2da1e680ecce1cba46243983b" "/opt/rustwide/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ec040a0444bdbf1e45782f49f824d83656d9cfaf251ea1b2dc819499cad6abee
[INFO] running `Command { std: "docker" "start" "-a" "ec040a0444bdbf1e45782f49f824d83656d9cfaf251ea1b2dc819499cad6abee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ec040a0444bdbf1e45782f49f824d83656d9cfaf251ea1b2dc819499cad6abee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ec040a0444bdbf1e45782f49f824d83656d9cfaf251ea1b2dc819499cad6abee", kill_on_drop: false }`
[INFO] [stdout] ec040a0444bdbf1e45782f49f824d83656d9cfaf251ea1b2dc819499cad6abee
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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:eea15d5475069c3ef791f10c2c6b5af2ee421ef2da1e680ecce1cba46243983b" "/opt/rustwide/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 98c2dcc28f8320de52c5c5752629a25e6d4ee128fd8963fa754ca97195d4c3fd
[INFO] running `Command { std: "docker" "start" "-a" "98c2dcc28f8320de52c5c5752629a25e6d4ee128fd8963fa754ca97195d4c3fd", kill_on_drop: false }`
[INFO] [stderr]    Compiling exercise v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `state`
[INFO] [stdout]   --> src/types_values.rs:54:9
[INFO] [stdout]    |
[INFO] [stdout] 54 |     let state = true;
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_state`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `name`
[INFO] [stdout]   --> src/types_values.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let name = "Diego Cuenca";
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_name`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `valor`
[INFO] [stdout]   --> src/types_values.rs:56:9
[INFO] [stdout]    |
[INFO] [stdout] 56 |     let valor = 23.32;
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_valor`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]    --> src/flow_control.rs:118:13
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn fizzbuzz(n: u32) -> u32 {
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `variables` is never used
[INFO] [stdout]  --> src/types_values.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn variables() {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `interproduct` is never used
[INFO] [stdout]   --> src/types_values.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub fn interproduct(a:i32, b:i32, c:i32) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `strings_demo` is never used
[INFO] [stdout]   --> src/types_values.rs:26:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | pub fn strings_demo() {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `takes_u32` is never used
[INFO] [stdout]   --> src/types_values.rs:42:4
[INFO] [stdout]    |
[INFO] [stdout] 42 | fn takes_u32(x: u32) {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `takes_i8` is never used
[INFO] [stdout]   --> src/types_values.rs:46:4
[INFO] [stdout]    |
[INFO] [stdout] 46 | fn takes_i8(y: i8) {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `types_inference` is never used
[INFO] [stdout]   --> src/types_values.rs:50:8
[INFO] [stdout]    |
[INFO] [stdout] 50 | pub fn types_inference(){
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fib` is never used
[INFO] [stdout]   --> src/types_values.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 | pub fn fib(n: u32) -> u32 {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `message` is never used
[INFO] [stdout]   --> src/types_values.rs:73:8
[INFO] [stdout]    |
[INFO] [stdout] 73 | pub fn message(message:&str) -> &str{
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `conditionals` is never used
[INFO] [stdout]  --> src/flow_control.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn conditionals(){
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bucles` is never used
[INFO] [stdout]   --> src/flow_control.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 | pub fn bucles(){
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bucles2` is never used
[INFO] [stdout]   --> src/flow_control.rs:46:8
[INFO] [stdout]    |
[INFO] [stdout] 46 | pub fn bucles2(){
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bucles3` is never used
[INFO] [stdout]   --> src/flow_control.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 | pub fn bucles3(){
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bloques` is never used
[INFO] [stdout]   --> src/flow_control.rs:78:8
[INFO] [stdout]    |
[INFO] [stdout] 78 | pub fn bloques(){
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `ambitos_var` is never used
[INFO] [stdout]   --> src/flow_control.rs:91:8
[INFO] [stdout]    |
[INFO] [stdout] 91 | pub fn ambitos_var(){
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `factorial` is never used
[INFO] [stdout]    --> src/flow_control.rs:110:8
[INFO] [stdout]     |
[INFO] [stdout] 110 | pub fn factorial(n: u32) -> u32 {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fizzbuzz` is never used
[INFO] [stdout]    --> src/flow_control.rs:118:4
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn fizzbuzz(n: u32) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `collatz_length` is never used
[INFO] [stdout]    --> src/flow_control.rs:123:8
[INFO] [stdout]     |
[INFO] [stdout] 123 | pub fn collatz_length(mut n: i32) -> i32 {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main` is never used
[INFO] [stdout]    --> src/flow_control.rs:135:6
[INFO] [stdout]     |
[INFO] [stdout] 135 |   fn main() {
[INFO] [stdout]     |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `tuples_arrays` is never used
[INFO] [stdout]  --> src/tuples_arrays.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn tuples_arrays(){
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.16s
[INFO] running `Command { std: "docker" "inspect" "98c2dcc28f8320de52c5c5752629a25e6d4ee128fd8963fa754ca97195d4c3fd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98c2dcc28f8320de52c5c5752629a25e6d4ee128fd8963fa754ca97195d4c3fd", kill_on_drop: false }`
[INFO] [stdout] 98c2dcc28f8320de52c5c5752629a25e6d4ee128fd8963fa754ca97195d4c3fd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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:eea15d5475069c3ef791f10c2c6b5af2ee421ef2da1e680ecce1cba46243983b" "/opt/rustwide/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 646ae1a834e330401ae04c9024033b9b067e5254f4741ca044b56d93d7b0c407
[INFO] running `Command { std: "docker" "start" "-a" "646ae1a834e330401ae04c9024033b9b067e5254f4741ca044b56d93d7b0c407", kill_on_drop: false }`
[INFO] [stderr]    Compiling exercise v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `state`
[INFO] [stdout]   --> src/types_values.rs:54:9
[INFO] [stdout]    |
[INFO] [stdout] 54 |     let state = true;
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_state`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `name`
[INFO] [stdout]   --> src/types_values.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let name = "Diego Cuenca";
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_name`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `valor`
[INFO] [stdout]   --> src/types_values.rs:56:9
[INFO] [stdout]    |
[INFO] [stdout] 56 |     let valor = 23.32;
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_valor`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]    --> src/flow_control.rs:118:13
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn fizzbuzz(n: u32) -> u32 {
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `variables` is never used
[INFO] [stdout]  --> src/types_values.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn variables() {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `interproduct` is never used
[INFO] [stdout]   --> src/types_values.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub fn interproduct(a:i32, b:i32, c:i32) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `strings_demo` is never used
[INFO] [stdout]   --> src/types_values.rs:26:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | pub fn strings_demo() {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `takes_u32` is never used
[INFO] [stdout]   --> src/types_values.rs:42:4
[INFO] [stdout]    |
[INFO] [stdout] 42 | fn takes_u32(x: u32) {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `takes_i8` is never used
[INFO] [stdout]   --> src/types_values.rs:46:4
[INFO] [stdout]    |
[INFO] [stdout] 46 | fn takes_i8(y: i8) {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `types_inference` is never used
[INFO] [stdout]   --> src/types_values.rs:50:8
[INFO] [stdout]    |
[INFO] [stdout] 50 | pub fn types_inference(){
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fib` is never used
[INFO] [stdout]   --> src/types_values.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 | pub fn fib(n: u32) -> u32 {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `message` is never used
[INFO] [stdout]   --> src/types_values.rs:73:8
[INFO] [stdout]    |
[INFO] [stdout] 73 | pub fn message(message:&str) -> &str{
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `conditionals` is never used
[INFO] [stdout]  --> src/flow_control.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn conditionals(){
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bucles` is never used
[INFO] [stdout]   --> src/flow_control.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 | pub fn bucles(){
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bucles2` is never used
[INFO] [stdout]   --> src/flow_control.rs:46:8
[INFO] [stdout]    |
[INFO] [stdout] 46 | pub fn bucles2(){
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bucles3` is never used
[INFO] [stdout]   --> src/flow_control.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 | pub fn bucles3(){
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bloques` is never used
[INFO] [stdout]   --> src/flow_control.rs:78:8
[INFO] [stdout]    |
[INFO] [stdout] 78 | pub fn bloques(){
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `ambitos_var` is never used
[INFO] [stdout]   --> src/flow_control.rs:91:8
[INFO] [stdout]    |
[INFO] [stdout] 91 | pub fn ambitos_var(){
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `factorial` is never used
[INFO] [stdout]    --> src/flow_control.rs:110:8
[INFO] [stdout]     |
[INFO] [stdout] 110 | pub fn factorial(n: u32) -> u32 {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fizzbuzz` is never used
[INFO] [stdout]    --> src/flow_control.rs:118:4
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn fizzbuzz(n: u32) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `collatz_length` is never used
[INFO] [stdout]    --> src/flow_control.rs:123:8
[INFO] [stdout]     |
[INFO] [stdout] 123 | pub fn collatz_length(mut n: i32) -> i32 {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main` is never used
[INFO] [stdout]    --> src/flow_control.rs:135:6
[INFO] [stdout]     |
[INFO] [stdout] 135 |   fn main() {
[INFO] [stdout]     |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `tuples_arrays` is never used
[INFO] [stdout]  --> src/tuples_arrays.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn tuples_arrays(){
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: linking with `cc` failed: exit status: 1
[INFO] [stdout]   |
[INFO] [stdout]   = note:  "cc" "-m64" "/tmp/rustcHLTgJJ/symbols.o" "<2 object files omitted>" "-Wl,--as-needed" "-Wl,-Bstatic" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib/{libtest-*,libgetopts-*,libunicode_width-*,librustc_std_workspace_std-*,libstd-*,libpanic_unwind-*,libobject-*,libmemchr-*,libaddr2line-*,libgimli-*,librustc_demangle-*,libstd_detect-*,libhashbrown-*,librustc_std_workspace_alloc-*,libminiz_oxide-*,libadler2-*,libunwind-*,libcfg_if-*,liblibc-*,liballoc-*,librustc_std_workspace_core-*,libcore-*,libcompiler_builtins-*}.rlib" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-L" "/tmp/rustcHLTgJJ/raw-dylibs" "-B<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/bin/gcc-ld" "-fuse-ld=lld" "-Wl,-znostart-stop-gc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "/opt/rustwide/target/debug/deps/exercise-3c0678d004041da3" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs"
[INFO] [stdout]   = note: some arguments are omitted. use `--verbose` to show all linker arguments
[INFO] [stdout]   = note: collect2: fatal error: ld terminated with signal 7 [Bus error], core dumped
[INFO] [stdout]           compilation terminated.
[INFO] [stdout]           
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `exercise` (bin "exercise" test) due to 1 previous error; 23 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "646ae1a834e330401ae04c9024033b9b067e5254f4741ca044b56d93d7b0c407", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "646ae1a834e330401ae04c9024033b9b067e5254f4741ca044b56d93d7b0c407", kill_on_drop: false }`
[INFO] [stdout] 646ae1a834e330401ae04c9024033b9b067e5254f4741ca044b56d93d7b0c407