[INFO] cloning repository https://github.com/Fifthrow/rust-kdb
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Fifthrow/rust-kdb" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFifthrow%2Frust-kdb", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFifthrow%2Frust-kdb'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 06ac2418a98fa1ad157156fef81c7e124d049d2d
[INFO] checking Fifthrow/rust-kdb against master#5a45ab9738330fb317d49e3594c2db5248b1e971 for pr-136303
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFifthrow%2Frust-kdb" "/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/Fifthrow/rust-kdb on toolchain 5a45ab9738330fb317d49e3594c2db5248b1e971
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+5a45ab9738330fb317d49e3594c2db5248b1e971" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Fifthrow/rust-kdb
[INFO] finished tweaking git repo https://github.com/Fifthrow/rust-kdb
[INFO] tweaked toml for git repo https://github.com/Fifthrow/rust-kdb written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Fifthrow/rust-kdb 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" "+5a45ab9738330fb317d49e3594c2db5248b1e971" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded array_iterator v1.3.0
[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:c80049f3b88b82089a44e0f06d0d6029d44b96b7257e55a1cd63dbc9f4c33334" "/opt/rustwide/cargo-home/bin/cargo" "+5a45ab9738330fb317d49e3594c2db5248b1e971" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e5e06c38a899ea8aaf862c02a09bd3fcdc744ffbadcf432ad9b25f15a3d6ef61
[INFO] running `Command { std: "docker" "start" "-a" "e5e06c38a899ea8aaf862c02a09bd3fcdc744ffbadcf432ad9b25f15a3d6ef61", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e5e06c38a899ea8aaf862c02a09bd3fcdc744ffbadcf432ad9b25f15a3d6ef61", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5e06c38a899ea8aaf862c02a09bd3fcdc744ffbadcf432ad9b25f15a3d6ef61", kill_on_drop: false }`
[INFO] [stdout] e5e06c38a899ea8aaf862c02a09bd3fcdc744ffbadcf432ad9b25f15a3d6ef61
[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=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:c80049f3b88b82089a44e0f06d0d6029d44b96b7257e55a1cd63dbc9f4c33334" "/opt/rustwide/cargo-home/bin/cargo" "+5a45ab9738330fb317d49e3594c2db5248b1e971" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4bab6bd8ae725f10b38a4ed1dd76bdf7775c479a57a37a6fa6eda81c45d3b3e0
[INFO] running `Command { std: "docker" "start" "-a" "4bab6bd8ae725f10b38a4ed1dd76bdf7775c479a57a37a6fa6eda81c45d3b3e0", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]    Compiling kdb v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking array_iterator v1.3.0
[INFO] [stderr]     Checking uuid v0.8.2
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling thiserror-impl v1.0.23
[INFO] [stderr]     Checking thiserror v1.0.23
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/k_error.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |         let mut err = KBox::new_atom(symbol(msg)).into_raw() as *mut K;
[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] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:51:63
[INFO] [stdout]     |
[INFO] [stdout] 51  |         let bytes = b9_serialize(SerializationMode::InProc, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                               ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `kbox::KBox<list::List<i32>>: AsRef<_>` found
[INFO] [stdout]    --> src/any.rs:106:1
[INFO] [stdout]     |
[INFO] [stdout] 106 | impl<T: KListable> AsRef<Any> for KBox<List<T>> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]    ::: src/kbox.rs:82:1
[INFO] [stdout]     |
[INFO] [stdout] 82  | impl<T: KObject> AsRef<T> for KBox<T> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 51  |         let bytes = b9_serialize(SerializationMode::InProc, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                             +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:51:63
[INFO] [stdout]     |
[INFO] [stdout] 51  |         let bytes = b9_serialize(SerializationMode::InProc, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                               ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `_: AsRef<any::Any>` found
[INFO] [stdout]    --> src/any.rs:40:1
[INFO] [stdout]     |
[INFO] [stdout] 40  | impl AsRef<Any> for Dictionary {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 46  | impl AsRef<Any> for Table {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 52  | impl AsRef<Any> for KError {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 118 | impl AsRef<Any> for KBox<Dictionary> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 124 | impl AsRef<Any> for KBox<Table> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     = note: required for `&_` to implement `AsRef<any::Any>`
[INFO] [stdout] note: required by a bound in `serialization::b9_serialize`
[INFO] [stdout]    --> src/serialization.rs:19:54
[INFO] [stdout]     |
[INFO] [stdout] 19  | pub fn b9_serialize(mode: SerializationMode, k: impl AsRef<Any>) -> Result<KBox<List<u8>>, KBox<KError>> {
[INFO] [stdout]     |                                                      ^^^^^^^^^^ required by this bound in `b9_serialize`
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 51  |         let bytes = b9_serialize(SerializationMode::InProc, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                             +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:55:66
[INFO] [stdout]     |
[INFO] [stdout] 55  |         let bytes = b9_serialize(SerializationMode::Enumerate, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                                  ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `kbox::KBox<list::List<i32>>: AsRef<_>` found
[INFO] [stdout]    --> src/any.rs:106:1
[INFO] [stdout]     |
[INFO] [stdout] 106 | impl<T: KListable> AsRef<Any> for KBox<List<T>> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]    ::: src/kbox.rs:82:1
[INFO] [stdout]     |
[INFO] [stdout] 82  | impl<T: KObject> AsRef<T> for KBox<T> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 55  |         let bytes = b9_serialize(SerializationMode::Enumerate, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                                +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:55:66
[INFO] [stdout]     |
[INFO] [stdout] 55  |         let bytes = b9_serialize(SerializationMode::Enumerate, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                                  ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `_: AsRef<any::Any>` found
[INFO] [stdout]    --> src/any.rs:40:1
[INFO] [stdout]     |
[INFO] [stdout] 40  | impl AsRef<Any> for Dictionary {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 46  | impl AsRef<Any> for Table {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 52  | impl AsRef<Any> for KError {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 118 | impl AsRef<Any> for KBox<Dictionary> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 124 | impl AsRef<Any> for KBox<Table> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     = note: required for `&_` to implement `AsRef<any::Any>`
[INFO] [stdout] note: required by a bound in `serialization::b9_serialize`
[INFO] [stdout]    --> src/serialization.rs:19:54
[INFO] [stdout]     |
[INFO] [stdout] 19  | pub fn b9_serialize(mode: SerializationMode, k: impl AsRef<Any>) -> Result<KBox<List<u8>>, KBox<KError>> {
[INFO] [stdout]     |                                                      ^^^^^^^^^^ required by this bound in `b9_serialize`
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 55  |         let bytes = b9_serialize(SerializationMode::Enumerate, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                                +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:59:68
[INFO] [stdout]     |
[INFO] [stdout] 59  |         let bytes = b9_serialize(SerializationMode::Unenumerate, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                                    ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `kbox::KBox<list::List<i32>>: AsRef<_>` found
[INFO] [stdout]    --> src/any.rs:106:1
[INFO] [stdout]     |
[INFO] [stdout] 106 | impl<T: KListable> AsRef<Any> for KBox<List<T>> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]    ::: src/kbox.rs:82:1
[INFO] [stdout]     |
[INFO] [stdout] 82  | impl<T: KObject> AsRef<T> for KBox<T> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 59  |         let bytes = b9_serialize(SerializationMode::Unenumerate, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                                  +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:59:68
[INFO] [stdout]     |
[INFO] [stdout] 59  |         let bytes = b9_serialize(SerializationMode::Unenumerate, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                                    ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `_: AsRef<any::Any>` found
[INFO] [stdout]    --> src/any.rs:40:1
[INFO] [stdout]     |
[INFO] [stdout] 40  | impl AsRef<Any> for Dictionary {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 46  | impl AsRef<Any> for Table {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 52  | impl AsRef<Any> for KError {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 118 | impl AsRef<Any> for KBox<Dictionary> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 124 | impl AsRef<Any> for KBox<Table> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     = note: required for `&_` to implement `AsRef<any::Any>`
[INFO] [stdout] note: required by a bound in `serialization::b9_serialize`
[INFO] [stdout]    --> src/serialization.rs:19:54
[INFO] [stdout]     |
[INFO] [stdout] 19  | pub fn b9_serialize(mode: SerializationMode, k: impl AsRef<Any>) -> Result<KBox<List<u8>>, KBox<KError>> {
[INFO] [stdout]     |                                                      ^^^^^^^^^^ required by this bound in `b9_serialize`
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 59  |         let bytes = b9_serialize(SerializationMode::Unenumerate, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                                  +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:63:65
[INFO] [stdout]     |
[INFO] [stdout] 63  |         let bytes = b9_serialize(SerializationMode::Compress, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                                 ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `kbox::KBox<list::List<i32>>: AsRef<_>` found
[INFO] [stdout]    --> src/any.rs:106:1
[INFO] [stdout]     |
[INFO] [stdout] 106 | impl<T: KListable> AsRef<Any> for KBox<List<T>> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]    ::: src/kbox.rs:82:1
[INFO] [stdout]     |
[INFO] [stdout] 82  | impl<T: KObject> AsRef<T> for KBox<T> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 63  |         let bytes = b9_serialize(SerializationMode::Compress, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                               +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]    --> src/serialization.rs:63:65
[INFO] [stdout]     |
[INFO] [stdout] 63  |         let bytes = b9_serialize(SerializationMode::Compress, l.as_ref()).unwrap();
[INFO] [stdout]     |                                                                 ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: multiple `impl`s satisfying `_: AsRef<any::Any>` found
[INFO] [stdout]    --> src/any.rs:40:1
[INFO] [stdout]     |
[INFO] [stdout] 40  | impl AsRef<Any> for Dictionary {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 46  | impl AsRef<Any> for Table {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 52  | impl AsRef<Any> for KError {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 118 | impl AsRef<Any> for KBox<Dictionary> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 124 | impl AsRef<Any> for KBox<Table> {
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     = note: required for `&_` to implement `AsRef<any::Any>`
[INFO] [stdout] note: required by a bound in `serialization::b9_serialize`
[INFO] [stdout]    --> src/serialization.rs:19:54
[INFO] [stdout]     |
[INFO] [stdout] 19  | pub fn b9_serialize(mode: SerializationMode, k: impl AsRef<Any>) -> Result<KBox<List<u8>>, KBox<KError>> {
[INFO] [stdout]     |                                                      ^^^^^^^^^^ required by this bound in `b9_serialize`
[INFO] [stdout] help: try using a fully qualified path to specify the expected types
[INFO] [stdout]     |
[INFO] [stdout] 63  |         let bytes = b9_serialize(SerializationMode::Compress, <kbox::KBox<list::List<i32>> as AsRef<T>>::as_ref(&l)).unwrap();
[INFO] [stdout]     |                                                               +++++++++++++++++++++++++++++++++++++++++++++++++++ ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/k_error.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |         let mut err = KBox::new_atom(symbol(msg)).into_raw() as *mut K;
[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] For more information about this error, try `rustc --explain E0283`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `kdb` (lib test) due to 8 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "4bab6bd8ae725f10b38a4ed1dd76bdf7775c479a57a37a6fa6eda81c45d3b3e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4bab6bd8ae725f10b38a4ed1dd76bdf7775c479a57a37a6fa6eda81c45d3b3e0", kill_on_drop: false }`
[INFO] [stdout] 4bab6bd8ae725f10b38a4ed1dd76bdf7775c479a57a37a6fa6eda81c45d3b3e0
