[INFO] fetching crate len_constraints 0.1.2...
[INFO] building len_constraints-0.1.2 against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] extracting crate len_constraints 0.1.2 into /workspace/builds/worker-6-tc1/source
[INFO] validating manifest of crates.io crate len_constraints 0.1.2 on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate len_constraints 0.1.2
[INFO] finished tweaking crates.io crate len_constraints 0.1.2
[INFO] tweaked toml for crates.io crate len_constraints 0.1.2 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 75e631eb70152534d11decdb2b0453c0ed12881de1e1cd5ce040e43bdde1966c
[INFO] running `Command { std: "docker" "start" "-a" "75e631eb70152534d11decdb2b0453c0ed12881de1e1cd5ce040e43bdde1966c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "75e631eb70152534d11decdb2b0453c0ed12881de1e1cd5ce040e43bdde1966c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "75e631eb70152534d11decdb2b0453c0ed12881de1e1cd5ce040e43bdde1966c", kill_on_drop: false }`
[INFO] [stdout] 75e631eb70152534d11decdb2b0453c0ed12881de1e1cd5ce040e43bdde1966c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5cd06e4caa4fe89a0e762422b98d96a7f1653e1d5914e81c888b2e4c0f272472
[INFO] running `Command { std: "docker" "start" "-a" "5cd06e4caa4fe89a0e762422b98d96a7f1653e1d5914e81c888b2e4c0f272472", kill_on_drop: false }`
[INFO] [stderr]    Compiling len_constraints v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:41:51
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>>;
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>>;
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:48:51
[INFO] [stdout]    |
[INFO] [stdout] 48 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 48 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:57:51
[INFO] [stdout]    |
[INFO] [stdout] 57 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:66:51
[INFO] [stdout]    |
[INFO] [stdout] 66 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 66 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:75:51
[INFO] [stdout]    |
[INFO] [stdout] 75 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 75 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:100:73
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn try_from(slice: &'a[T], relative_to: usize) -> Result<Self, Box<Error + 'static>> {
[INFO] [stdout]     |                                                                            ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn try_from(slice: &'a[T], relative_to: usize) -> Result<Self, Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:107:63
[INFO] [stdout]     |
[INFO] [stdout] 107 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                  ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 107 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:113:64
[INFO] [stdout]     |
[INFO] [stdout] 113 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<Error + 'static>> {
[INFO] [stdout]     |                                                                   ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 113 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:124:77
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn try_from(slice: &'a mut[T], relative_to: usize) -> Result<Self, Box<Error + 'static>> {
[INFO] [stdout]     |                                                                                ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn try_from(slice: &'a mut[T], relative_to: usize) -> Result<Self, Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:131:63
[INFO] [stdout]     |
[INFO] [stdout] 131 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                  ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 131 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:137:71
[INFO] [stdout]     |
[INFO] [stdout] 137 |     pub fn slice_mut(self, relative_to: usize) -> Result<&'a mut[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                          ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 137 |     pub fn slice_mut(self, relative_to: usize) -> Result<&'a mut[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:143:64
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<Error + 'static>> {
[INFO] [stdout]     |                                                                   ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice.rs:57:19
[INFO] [stdout]    |
[INFO] [stdout] 57 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice.rs:76:19
[INFO] [stdout]    |
[INFO] [stdout] 76 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 76 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice_mut.rs:81:19
[INFO] [stdout]    |
[INFO] [stdout] 81 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 81 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:100:19
[INFO] [stdout]     |
[INFO] [stdout] 100 |     type Error = Box<Error + 'static>;
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 100 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]     |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.15s
[INFO] running `Command { std: "docker" "inspect" "5cd06e4caa4fe89a0e762422b98d96a7f1653e1d5914e81c888b2e4c0f272472", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5cd06e4caa4fe89a0e762422b98d96a7f1653e1d5914e81c888b2e4c0f272472", kill_on_drop: false }`
[INFO] [stdout] 5cd06e4caa4fe89a0e762422b98d96a7f1653e1d5914e81c888b2e4c0f272472
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4beaa723d926d81e5ff338df9fc3952a1168ea1e305557ca51428012847fe4df
[INFO] running `Command { std: "docker" "start" "-a" "4beaa723d926d81e5ff338df9fc3952a1168ea1e305557ca51428012847fe4df", kill_on_drop: false }`
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:41:51
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>>;
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>>;
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:48:51
[INFO] [stdout]    |
[INFO] [stdout] 48 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 48 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling len_constraints v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:57:51
[INFO] [stdout]    |
[INFO] [stdout] 57 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:66:51
[INFO] [stdout]    |
[INFO] [stdout] 66 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 66 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:75:51
[INFO] [stdout]    |
[INFO] [stdout] 75 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 75 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:100:73
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn try_from(slice: &'a[T], relative_to: usize) -> Result<Self, Box<Error + 'static>> {
[INFO] [stdout]     |                                                                            ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn try_from(slice: &'a[T], relative_to: usize) -> Result<Self, Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:107:63
[INFO] [stdout]     |
[INFO] [stdout] 107 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                  ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 107 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:113:64
[INFO] [stdout]     |
[INFO] [stdout] 113 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<Error + 'static>> {
[INFO] [stdout]     |                                                                   ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 113 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:124:77
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn try_from(slice: &'a mut[T], relative_to: usize) -> Result<Self, Box<Error + 'static>> {
[INFO] [stdout]     |                                                                                ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn try_from(slice: &'a mut[T], relative_to: usize) -> Result<Self, Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:131:63
[INFO] [stdout]     |
[INFO] [stdout] 131 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                  ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 131 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:137:71
[INFO] [stdout]     |
[INFO] [stdout] 137 |     pub fn slice_mut(self, relative_to: usize) -> Result<&'a mut[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                          ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 137 |     pub fn slice_mut(self, relative_to: usize) -> Result<&'a mut[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:143:64
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<Error + 'static>> {
[INFO] [stdout]     |                                                                   ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice.rs:57:19
[INFO] [stdout]    |
[INFO] [stdout] 57 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice.rs:76:19
[INFO] [stdout]    |
[INFO] [stdout] 76 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 76 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice_mut.rs:81:19
[INFO] [stdout]    |
[INFO] [stdout] 81 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 81 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:100:19
[INFO] [stdout]     |
[INFO] [stdout] 100 |     type Error = Box<Error + 'static>;
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 100 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]     |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> tests/constraint_macro.rs:10:29
[INFO] [stdout]    |
[INFO] [stdout] 10 | fn test() -> Result<(), Box<Error + 'static>> {
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 10 | fn test() -> Result<(), Box<dyn Error + 'static>> {
[INFO] [stdout]    |                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:41:51
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>>;
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>>;
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:48:51
[INFO] [stdout]    |
[INFO] [stdout] 48 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 48 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:57:51
[INFO] [stdout]    |
[INFO] [stdout] 57 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:66:51
[INFO] [stdout]    |
[INFO] [stdout] 66 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 66 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/type_math.rs:75:51
[INFO] [stdout]    |
[INFO] [stdout] 75 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<Error + 'static>> {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 75 |     fn r#do(a: usize, b: usize) -> Result<usize, Box<dyn Error + 'static>> {
[INFO] [stdout]    |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:100:73
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn try_from(slice: &'a[T], relative_to: usize) -> Result<Self, Box<Error + 'static>> {
[INFO] [stdout]     |                                                                            ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn try_from(slice: &'a[T], relative_to: usize) -> Result<Self, Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:107:63
[INFO] [stdout]     |
[INFO] [stdout] 107 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                  ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 107 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice.rs:113:64
[INFO] [stdout]     |
[INFO] [stdout] 113 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<Error + 'static>> {
[INFO] [stdout]     |                                                                   ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 113 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:124:77
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn try_from(slice: &'a mut[T], relative_to: usize) -> Result<Self, Box<Error + 'static>> {
[INFO] [stdout]     |                                                                                ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn try_from(slice: &'a mut[T], relative_to: usize) -> Result<Self, Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:131:63
[INFO] [stdout]     |
[INFO] [stdout] 131 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                  ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 131 |     pub fn slice(self, relative_to: usize) -> Result<&'a[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:137:71
[INFO] [stdout]     |
[INFO] [stdout] 137 |     pub fn slice_mut(self, relative_to: usize) -> Result<&'a mut[T], Box<Error + 'static>> {
[INFO] [stdout]     |                                                                          ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 137 |     pub fn slice_mut(self, relative_to: usize) -> Result<&'a mut[T], Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:143:64
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<Error + 'static>> {
[INFO] [stdout]     |                                                                   ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn validate(len: usize, relative_to: usize) -> Result<(), Box<dyn Error + 'static>> {
[INFO] [stdout]     |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice.rs:57:19
[INFO] [stdout]    |
[INFO] [stdout] 57 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice.rs:76:19
[INFO] [stdout]    |
[INFO] [stdout] 76 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 76 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/slice_mut.rs:81:19
[INFO] [stdout]    |
[INFO] [stdout] 81 |     type Error = Box<Error + 'static>;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 81 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/slice_mut.rs:100:19
[INFO] [stdout]     |
[INFO] [stdout] 100 |     type Error = Box<Error + 'static>;
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) 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 a dyn-compatible trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 100 |     type Error = Box<dyn Error + 'static>;
[INFO] [stdout]     |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.56s
[INFO] running `Command { std: "docker" "inspect" "4beaa723d926d81e5ff338df9fc3952a1168ea1e305557ca51428012847fe4df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4beaa723d926d81e5ff338df9fc3952a1168ea1e305557ca51428012847fe4df", kill_on_drop: false }`
[INFO] [stdout] 4beaa723d926d81e5ff338df9fc3952a1168ea1e305557ca51428012847fe4df