[INFO] cloning repository https://github.com/yavrib/rust-closures-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/yavrib/rust-closures-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyavrib%2Frust-closures-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyavrib%2Frust-closures-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ac31b4f22d24ab919d6edb5ab9396af3f9bbecc3
[INFO] checking yavrib/rust-closures-playground against master#af4a5a13a15fa0c60e06321077ef452f769b42fd for pr-122960-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyavrib%2Frust-closures-playground" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/yavrib/rust-closures-playground on toolchain af4a5a13a15fa0c60e06321077ef452f769b42fd
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/yavrib/rust-closures-playground
[INFO] finished tweaking git repo https://github.com/yavrib/rust-closures-playground
[INFO] tweaked toml for git repo https://github.com/yavrib/rust-closures-playground written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/yavrib/rust-closures-playground 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" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d22966faa718675d9d5257a95c3e01437b8386deb00e68bd2f67724faf6c12f3
[INFO] running `Command { std: "docker" "start" "-a" "d22966faa718675d9d5257a95c3e01437b8386deb00e68bd2f67724faf6c12f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d22966faa718675d9d5257a95c3e01437b8386deb00e68bd2f67724faf6c12f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d22966faa718675d9d5257a95c3e01437b8386deb00e68bd2f67724faf6c12f3", kill_on_drop: false }`
[INFO] [stdout] d22966faa718675d9d5257a95c3e01437b8386deb00e68bd2f67724faf6c12f3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4bba79e02f0d4e1b96747492cada6fb64e2f419a8208445ee99bbc9a62457f39
[INFO] running `Command { std: "docker" "start" "-a" "4bba79e02f0d4e1b96747492cada6fb64e2f419a8208445ee99bbc9a62457f39", kill_on_drop: false }`
[INFO] [stderr]     Checking rust-closures-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0106]: missing lifetime specifier
[INFO] [stdout]  --> src/main.rs:3:57
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                         ^ expected named lifetime parameter
[INFO] [stdout]   |
[INFO] [stdout]   = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from
[INFO] [stdout] help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static`
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]   |                                                          +++++++
[INFO] [stdout] help: instead, you are more likely to want to return an owned value
[INFO] [stdout]   |
[INFO] [stdout] 3 -     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout] 3 +     fn no_lifetime_specified_higher_order_function() -> (Fn(i32) -> i32) {
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0106]: missing lifetime specifier
[INFO] [stdout]  --> src/main.rs:3:57
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                         ^ expected named lifetime parameter
[INFO] [stdout]   |
[INFO] [stdout]   = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from
[INFO] [stdout] help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static`
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]   |                                                          +++++++
[INFO] [stdout] help: instead, you are more likely to want to return an owned value
[INFO] [stdout]   |
[INFO] [stdout] 3 -     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout] 3 +     fn no_lifetime_specified_higher_order_function() -> (Fn(i32) -> i32) {
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]  --> src/main.rs:3:58
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                          ^              ^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]   |
[INFO] [stdout] 3 -     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout] 3 +     fn no_lifetime_specified_higher_order_function() -> &Fn(i32) -> i32 {
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/main.rs:10:70
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]    |                                                                      ^              ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 10 -     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout] 10 +     fn static_lifetime_specified_higher_order_function() -> &'static Fn(i32) -> i32 {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/main.rs:3:59
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                           ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]   = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(dyn Fn(i32) -> i32) {
[INFO] [stdout]   |                                                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]  --> src/main.rs:3:58
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                          ^              ^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]   |
[INFO] [stdout] 3 -     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout] 3 +     fn no_lifetime_specified_higher_order_function() -> &Fn(i32) -> i32 {
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/main.rs:10:70
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]    |                                                                      ^              ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 10 -     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout] 10 +     fn static_lifetime_specified_higher_order_function() -> &'static Fn(i32) -> i32 {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/main.rs:3:59
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                           ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]   = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(dyn Fn(i32) -> i32) {
[INFO] [stdout]   |                                                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:10:71
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]    |                                                                       ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (dyn Fn(i32) -> i32) {
[INFO] [stdout]    |                                                                       +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:17:45
[INFO] [stdout]    |
[INFO] [stdout] 17 |     fn boxed_higher_order_function() -> Box<Fn(i32) -> i32> {
[INFO] [stdout]    |                                             ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 17 |     fn boxed_higher_order_function() -> Box<dyn Fn(i32) -> i32> {
[INFO] [stdout]    |                                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:23:39
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn higher_order_function() -> Box<Fn(i32) -> i32> {
[INFO] [stdout]    |                                       ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn higher_order_function() -> Box<dyn Fn(i32) -> i32> {
[INFO] [stdout]    |                                       +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:10:71
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]    |                                                                       ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (dyn Fn(i32) -> i32) {
[INFO] [stdout]    |                                                                       +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:17:45
[INFO] [stdout]    |
[INFO] [stdout] 17 |     fn boxed_higher_order_function() -> Box<Fn(i32) -> i32> {
[INFO] [stdout]    |                                             ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 17 |     fn boxed_higher_order_function() -> Box<dyn Fn(i32) -> i32> {
[INFO] [stdout]    |                                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:23:39
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn higher_order_function() -> Box<Fn(i32) -> i32> {
[INFO] [stdout]    |                                       ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn higher_order_function() -> Box<dyn Fn(i32) -> i32> {
[INFO] [stdout]    |                                       +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]  --> src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                         ----------------- expected `&'static (dyn Fn(i32) -> i32 + 'static)` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 6 |         |x| x + num
[INFO] [stdout]   |         ^^^^^^^^^^^ expected `&dyn Fn(i32) -> i32`, found closure
[INFO] [stdout]   |
[INFO] [stdout]   = note: expected reference `&'static (dyn Fn(i32) -> i32 + 'static)`
[INFO] [stdout]                found closure `{closure@src/main.rs:6:9: 6:12}`
[INFO] [stdout] help: consider borrowing here
[INFO] [stdout]   |
[INFO] [stdout] 6 |         &|x| x + num
[INFO] [stdout]   |         +
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]  --> src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     fn no_lifetime_specified_higher_order_function() -> &(Fn(i32) -> i32) {
[INFO] [stdout]   |                                                         ----------------- expected `&'static (dyn Fn(i32) -> i32 + 'static)` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 6 |         |x| x + num
[INFO] [stdout]   |         ^^^^^^^^^^^ expected `&dyn Fn(i32) -> i32`, found closure
[INFO] [stdout]   |
[INFO] [stdout]   = note: expected reference `&'static (dyn Fn(i32) -> i32 + 'static)`
[INFO] [stdout]                found closure `{closure@src/main.rs:6:9: 6:12}`
[INFO] [stdout] help: consider borrowing here
[INFO] [stdout]   |
[INFO] [stdout] 6 |         &|x| x + num
[INFO] [stdout]   |         +
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> src/main.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]    |                                                             ------------------------- expected `&'static (dyn Fn(i32) -> i32 + 'static)` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 13 |         |x| x + num
[INFO] [stdout]    |         ^^^^^^^^^^^ expected `&dyn Fn(i32) -> i32`, found closure
[INFO] [stdout]    |
[INFO] [stdout]    = note: expected reference `&'static (dyn Fn(i32) -> i32 + 'static)`
[INFO] [stdout]                 found closure `{closure@src/main.rs:13:9: 13:12}`
[INFO] [stdout] help: consider borrowing here
[INFO] [stdout]    |
[INFO] [stdout] 13 |         &|x| x + num
[INFO] [stdout]    |         +
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> src/main.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn static_lifetime_specified_higher_order_function() -> &'static (Fn(i32) -> i32) {
[INFO] [stdout]    |                                                             ------------------------- expected `&'static (dyn Fn(i32) -> i32 + 'static)` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 13 |         |x| x + num
[INFO] [stdout]    |         ^^^^^^^^^^^ expected `&dyn Fn(i32) -> i32`, found closure
[INFO] [stdout]    |
[INFO] [stdout]    = note: expected reference `&'static (dyn Fn(i32) -> i32 + 'static)`
[INFO] [stdout]                 found closure `{closure@src/main.rs:13:9: 13:12}`
[INFO] [stdout] help: consider borrowing here
[INFO] [stdout]    |
[INFO] [stdout] 13 |         &|x| x + num
[INFO] [stdout]    |         +
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0373]: closure may outlive the current function, but it borrows `num`, which is owned by the current function
[INFO] [stdout]   --> src/main.rs:20:18
[INFO] [stdout]    |
[INFO] [stdout] 20 |         Box::new(|x| x + num)
[INFO] [stdout]    |                  ^^^     --- `num` is borrowed here
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  may outlive borrowed value `num`
[INFO] [stdout]    |
[INFO] [stdout] note: closure is returned here
[INFO] [stdout]   --> src/main.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |         Box::new(|x| x + num)
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] help: to force the closure to take ownership of `num` (and any other referenced variables), use the `move` keyword
[INFO] [stdout]    |
[INFO] [stdout] 20 |         Box::new(move |x| x + num)
[INFO] [stdout]    |                  ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0373]: closure may outlive the current function, but it borrows `num`, which is owned by the current function
[INFO] [stdout]   --> src/main.rs:20:18
[INFO] [stdout]    |
[INFO] [stdout] 20 |         Box::new(|x| x + num)
[INFO] [stdout]    |                  ^^^     --- `num` is borrowed here
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  may outlive borrowed value `num`
[INFO] [stdout]    |
[INFO] [stdout] note: closure is returned here
[INFO] [stdout]   --> src/main.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |         Box::new(|x| x + num)
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] help: to force the closure to take ownership of `num` (and any other referenced variables), use the `move` keyword
[INFO] [stdout]    |
[INFO] [stdout] 20 |         Box::new(move |x| x + num)
[INFO] [stdout]    |                  ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors; 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0106, E0308, E0373.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0106`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors; 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0106, E0308, E0373.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0106`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust-closures-playground` (bin "rust-closures-playground" test) due to 5 previous errors; 6 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `rust-closures-playground` (bin "rust-closures-playground") due to 5 previous errors; 6 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "4bba79e02f0d4e1b96747492cada6fb64e2f419a8208445ee99bbc9a62457f39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4bba79e02f0d4e1b96747492cada6fb64e2f419a8208445ee99bbc9a62457f39", kill_on_drop: false }`
[INFO] [stdout] 4bba79e02f0d4e1b96747492cada6fb64e2f419a8208445ee99bbc9a62457f39