[INFO] fetching crate prefixopt 0.4.0...
[INFO] building prefixopt-0.4.0 against master#d5c88c22807925c189328ef9d923c5d2b11a95b8 for pr-87066-3
[INFO] extracting crate prefixopt 0.4.0 into /workspace/builds/worker-72/source
[INFO] validating manifest of crates.io crate prefixopt 0.4.0 on toolchain d5c88c22807925c189328ef9d923c5d2b11a95b8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate prefixopt 0.4.0
[INFO] finished tweaking crates.io crate prefixopt 0.4.0
[INFO] tweaked toml for crates.io crate prefixopt 0.4.0 written to /workspace/builds/worker-72/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded scopeguard v0.2.0
[INFO] [stderr]   Downloaded map_in_place v0.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a9638566bc839250e27d2e9db05d530ee60b5403a4a696abf7d23c48aef1008c
[INFO] running `Command { std: "docker" "start" "-a" "a9638566bc839250e27d2e9db05d530ee60b5403a4a696abf7d23c48aef1008c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a9638566bc839250e27d2e9db05d530ee60b5403a4a696abf7d23c48aef1008c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a9638566bc839250e27d2e9db05d530ee60b5403a4a696abf7d23c48aef1008c", kill_on_drop: false }`
[INFO] [stdout] a9638566bc839250e27d2e9db05d530ee60b5403a4a696abf7d23c48aef1008c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cb7de38d1a7f818f6d39c16121334e85968b9fca62d50beddf16c374d0fc48fc
[INFO] running `Command { std: "docker" "start" "-a" "cb7de38d1a7f818f6d39c16121334e85968b9fca62d50beddf16c374d0fc48fc", kill_on_drop: false }`
[INFO] [stderr]    Compiling scopeguard v0.2.0
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling map_in_place v0.1.0
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling prefixopt v0.4.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:56:42
[INFO] [stdout]    |
[INFO] [stdout] 56 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:80:42
[INFO] [stdout]    |
[INFO] [stdout] 80 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:98:42
[INFO] [stdout]    |
[INFO] [stdout] 98 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/core.rs:9:69
[INFO] [stdout]   |
[INFO] [stdout] 9 |         Self::Container::concat_prefix(&ConcatRef::from(&prefix as &Display))
[INFO] [stdout]   |                                                                     ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/core.rs:15:42
[INFO] [stdout]    |
[INFO] [stdout] 15 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self;
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/std_impl.rs:13:42
[INFO] [stdout]    |
[INFO] [stdout] 13 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/std_impl.rs:39:42
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> bin/example_1.rs:53:42
[INFO] [stdout]    |
[INFO] [stdout] 53 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> bin/example_1.rs:68:42
[INFO] [stdout]    |
[INFO] [stdout] 68 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 10.61s
[INFO] running `Command { std: "docker" "inspect" "cb7de38d1a7f818f6d39c16121334e85968b9fca62d50beddf16c374d0fc48fc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cb7de38d1a7f818f6d39c16121334e85968b9fca62d50beddf16c374d0fc48fc", kill_on_drop: false }`
[INFO] [stdout] cb7de38d1a7f818f6d39c16121334e85968b9fca62d50beddf16c374d0fc48fc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 97fab848886705c6722e4c48aa4cfef9c82ef4c185a81822bfe82cb0db8a9047
[INFO] running `Command { std: "docker" "start" "-a" "97fab848886705c6722e4c48aa4cfef9c82ef4c185a81822bfe82cb0db8a9047", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling prefixopt v0.4.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:56:42
[INFO] [stdout]    |
[INFO] [stdout] 56 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:80:42
[INFO] [stdout]    |
[INFO] [stdout] 80 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:98:42
[INFO] [stdout]    |
[INFO] [stdout] 98 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/core.rs:9:69
[INFO] [stdout]   |
[INFO] [stdout] 9 |         Self::Container::concat_prefix(&ConcatRef::from(&prefix as &Display))
[INFO] [stdout]   |                                                                     ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/core.rs:15:42
[INFO] [stdout]    |
[INFO] [stdout] 15 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self;
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/std_impl.rs:13:42
[INFO] [stdout]    |
[INFO] [stdout] 13 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/std_impl.rs:39:42
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> bin/example_1.rs:53:42
[INFO] [stdout]    |
[INFO] [stdout] 53 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> bin/example_1.rs:68:42
[INFO] [stdout]    |
[INFO] [stdout] 68 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> bin/example_1.rs:53:42
[INFO] [stdout]    |
[INFO] [stdout] 53 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> bin/example_1.rs:68:42
[INFO] [stdout]    |
[INFO] [stdout] 68 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:56:42
[INFO] [stdout]    |
[INFO] [stdout] 56 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:80:42
[INFO] [stdout]    |
[INFO] [stdout] 80 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/parsable.rs:98:42
[INFO] [stdout]    |
[INFO] [stdout] 98 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/core.rs:9:69
[INFO] [stdout]   |
[INFO] [stdout] 9 |         Self::Container::concat_prefix(&ConcatRef::from(&prefix as &Display))
[INFO] [stdout]   |                                                                     ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/core.rs:15:42
[INFO] [stdout]    |
[INFO] [stdout] 15 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self;
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/std_impl.rs:13:42
[INFO] [stdout]    |
[INFO] [stdout] 13 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/std_impl.rs:39:42
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn concat_prefix(prefix: &ConcatRef<&Display>) -> Self {
[INFO] [stdout]    |                                          ^^^^^^^ help: use `dyn`: `dyn Display`
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.27s
[INFO] running `Command { std: "docker" "inspect" "97fab848886705c6722e4c48aa4cfef9c82ef4c185a81822bfe82cb0db8a9047", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "97fab848886705c6722e4c48aa4cfef9c82ef4c185a81822bfe82cb0db8a9047", kill_on_drop: false }`
[INFO] [stdout] 97fab848886705c6722e4c48aa4cfef9c82ef4c185a81822bfe82cb0db8a9047