[INFO] fetching crate argf 0.2.0...
[INFO] checking argf-0.2.0 against master#b3bd7058c139e71bae0862ef8f8ac936208873e9 for pr-123752
[INFO] extracting crate argf 0.2.0 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate argf 0.2.0 on toolchain b3bd7058c139e71bae0862ef8f8ac936208873e9
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b3bd7058c139e71bae0862ef8f8ac936208873e9" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate argf 0.2.0
[INFO] finished tweaking crates.io crate argf 0.2.0
[INFO] tweaked toml for crates.io crate argf 0.2.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b3bd7058c139e71bae0862ef8f8ac936208873e9" "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" "+b3bd7058c139e71bae0862ef8f8ac936208873e9" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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" "+b3bd7058c139e71bae0862ef8f8ac936208873e9" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d364a7127f2bed555bd01512d8060735f13dd5addc2d02765be5957472d40348
[INFO] running `Command { std: "docker" "start" "-a" "d364a7127f2bed555bd01512d8060735f13dd5addc2d02765be5957472d40348", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d364a7127f2bed555bd01512d8060735f13dd5addc2d02765be5957472d40348", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d364a7127f2bed555bd01512d8060735f13dd5addc2d02765be5957472d40348", kill_on_drop: false }`
[INFO] [stdout] d364a7127f2bed555bd01512d8060735f13dd5addc2d02765be5957472d40348
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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" "+b3bd7058c139e71bae0862ef8f8ac936208873e9" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5c75b11ffa211ab78709ab679373159b4f97b6e4bb574fb29cef61e0bb1e75f4
[INFO] running `Command { std: "docker" "start" "-a" "5c75b11ffa211ab78709ab679373159b4f97b6e4bb574fb29cef61e0bb1e75f4", kill_on_drop: false }`
[INFO] [stderr]     Checking argf v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Iterator` is imported redundantly
[INFO] [stdout]  --> src/lib.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::iter::Iterator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/b3bd7058c139e71bae0862ef8f8ac936208873e9/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Iterator` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Iterator` is imported redundantly
[INFO] [stdout]  --> src/lib.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::iter::Iterator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/b3bd7058c139e71bae0862ef8f8ac936208873e9/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Iterator` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/lib.rs:5:32
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn from_arguments() -> Box<io::Read> {
[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] 5 | pub fn from_arguments() -> Box<dyn io::Read> {
[INFO] [stdout]   |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/lib.rs:5:32
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn from_arguments() -> Box<io::Read> {
[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] 5 | pub fn from_arguments() -> Box<dyn io::Read> {
[INFO] [stdout]   |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:10:42
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub fn from_slice<I>(input: &[I]) -> Box<io::Read>
[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 | pub fn from_slice<I>(input: &[I]) -> Box<dyn io::Read>
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:20:40
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn to_reader<'a>(path: &'a str) -> Box<io::Read> {
[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] 20 | fn to_reader<'a>(path: &'a str) -> Box<dyn io::Read> {
[INFO] [stdout]    |                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:10:42
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub fn from_slice<I>(input: &[I]) -> Box<io::Read>
[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 | pub fn from_slice<I>(input: &[I]) -> Box<dyn io::Read>
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:20:40
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn to_reader<'a>(path: &'a str) -> Box<io::Read> {
[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] 20 | fn to_reader<'a>(path: &'a str) -> Box<dyn io::Read> {
[INFO] [stdout]    |                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:13:24
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let mut chain: Box<Read> = Box::new(std::io::empty().chain(std::io::empty()));
[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] 13 |     let mut chain: Box<dyn Read> = Box::new(std::io::empty().chain(std::io::empty()));
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:13:24
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let mut chain: Box<Read> = Box::new(std::io::empty().chain(std::io::empty()));
[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] 13 |     let mut chain: Box<dyn Read> = Box::new(std::io::empty().chain(std::io::empty()));
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.04s
[INFO] running `Command { std: "docker" "inspect" "5c75b11ffa211ab78709ab679373159b4f97b6e4bb574fb29cef61e0bb1e75f4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5c75b11ffa211ab78709ab679373159b4f97b6e4bb574fb29cef61e0bb1e75f4", kill_on_drop: false }`
[INFO] [stdout] 5c75b11ffa211ab78709ab679373159b4f97b6e4bb574fb29cef61e0bb1e75f4
[INFO] checking argf-0.2.0 against try#57fe1b734d9ff1c8a92bda60b85506b9648158d3 for pr-123752
[INFO] extracting crate argf 0.2.0 into /workspace/builds/worker-4-tc2/source
[INFO] validating manifest of crates.io crate argf 0.2.0 on toolchain 57fe1b734d9ff1c8a92bda60b85506b9648158d3
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+57fe1b734d9ff1c8a92bda60b85506b9648158d3" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate argf 0.2.0
[INFO] finished tweaking crates.io crate argf 0.2.0
[INFO] tweaked toml for crates.io crate argf 0.2.0 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+57fe1b734d9ff1c8a92bda60b85506b9648158d3" "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" "+57fe1b734d9ff1c8a92bda60b85506b9648158d3" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "+57fe1b734d9ff1c8a92bda60b85506b9648158d3" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] faec3696ab33a11a9f9b641dc730e45b93657feee87f0fa87fdb2fd60db801a3
[INFO] running `Command { std: "docker" "start" "-a" "faec3696ab33a11a9f9b641dc730e45b93657feee87f0fa87fdb2fd60db801a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "faec3696ab33a11a9f9b641dc730e45b93657feee87f0fa87fdb2fd60db801a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "faec3696ab33a11a9f9b641dc730e45b93657feee87f0fa87fdb2fd60db801a3", kill_on_drop: false }`
[INFO] [stdout] faec3696ab33a11a9f9b641dc730e45b93657feee87f0fa87fdb2fd60db801a3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "+57fe1b734d9ff1c8a92bda60b85506b9648158d3" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] dfeedfc726862aafe1cc86bc6112ab6cf5e163766c91803d749702805be1bc8c
[INFO] running `Command { std: "docker" "start" "-a" "dfeedfc726862aafe1cc86bc6112ab6cf5e163766c91803d749702805be1bc8c", kill_on_drop: false }`
[INFO] [stderr]     Checking argf v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Iterator` is imported redundantly
[INFO] [stdout]  --> src/lib.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::iter::Iterator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/57fe1b734d9ff1c8a92bda60b85506b9648158d3/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Iterator` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Iterator` is imported redundantly
[INFO] [stdout]  --> src/lib.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::iter::Iterator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/57fe1b734d9ff1c8a92bda60b85506b9648158d3/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Iterator` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/lib.rs:5:32
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn from_arguments() -> Box<io::Read> {
[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] 5 | pub fn from_arguments() -> Box<dyn io::Read> {
[INFO] [stdout]   |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/lib.rs:5:32
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn from_arguments() -> Box<io::Read> {
[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] 5 | pub fn from_arguments() -> Box<dyn io::Read> {
[INFO] [stdout]   |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:10:42
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub fn from_slice<I>(input: &[I]) -> Box<io::Read>
[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 | pub fn from_slice<I>(input: &[I]) -> Box<dyn io::Read>
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:10:42
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub fn from_slice<I>(input: &[I]) -> Box<io::Read>
[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 | pub fn from_slice<I>(input: &[I]) -> Box<dyn io::Read>
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:20:40
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn to_reader<'a>(path: &'a str) -> Box<io::Read> {
[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] 20 | fn to_reader<'a>(path: &'a str) -> Box<dyn io::Read> {
[INFO] [stdout]    |                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:20:40
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn to_reader<'a>(path: &'a str) -> Box<io::Read> {
[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] 20 | fn to_reader<'a>(path: &'a str) -> Box<dyn io::Read> {
[INFO] [stdout]    |                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:13:24
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let mut chain: Box<Read> = Box::new(std::io::empty().chain(std::io::empty()));
[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] 13 |     let mut chain: Box<dyn Read> = Box::new(std::io::empty().chain(std::io::empty()));
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:13:24
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let mut chain: Box<Read> = Box::new(std::io::empty().chain(std::io::empty()));
[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] 13 |     let mut chain: Box<dyn Read> = Box::new(std::io::empty().chain(std::io::empty()));
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.03s
[INFO] running `Command { std: "docker" "inspect" "dfeedfc726862aafe1cc86bc6112ab6cf5e163766c91803d749702805be1bc8c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dfeedfc726862aafe1cc86bc6112ab6cf5e163766c91803d749702805be1bc8c", kill_on_drop: false }`
[INFO] [stdout] dfeedfc726862aafe1cc86bc6112ab6cf5e163766c91803d749702805be1bc8c
