[INFO] fetching crate ammonia 2.1.3...
[INFO] checking ammonia-2.1.3 against beta-2021-10-15 for beta-1.56-3
[INFO] extracting crate ammonia 2.1.3 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate ammonia 2.1.3 on toolchain beta-2021-10-15
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-10-15" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ammonia 2.1.3
[INFO] finished tweaking crates.io crate ammonia 2.1.3
[INFO] tweaked toml for crates.io crate ammonia 2.1.3 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate crates.io crate ammonia 2.1.3 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-10-15" "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-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-10-15" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] b4292df0e640ef45c9afbd8a45dcf8386ffb0a8f4d7e004b7b8624ada4949eca
[INFO] running `Command { std: "docker" "start" "-a" "b4292df0e640ef45c9afbd8a45dcf8386ffb0a8f4d7e004b7b8624ada4949eca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b4292df0e640ef45c9afbd8a45dcf8386ffb0a8f4d7e004b7b8624ada4949eca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b4292df0e640ef45c9afbd8a45dcf8386ffb0a8f4d7e004b7b8624ada4949eca", kill_on_drop: false }`
[INFO] [stdout] b4292df0e640ef45c9afbd8a45dcf8386ffb0a8f4d7e004b7b8624ada4949eca
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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=warn" "-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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-10-15" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] ae036a0d73e3d7c2fa3ac865f8a120a54a2c40bf96cc86556614b05bf819faec
[INFO] running `Command { std: "docker" "start" "-a" "ae036a0d73e3d7c2fa3ac865f8a120a54a2c40bf96cc86556614b05bf819faec", 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]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling libc v0.2.87
[INFO] [stderr]    Compiling siphasher v0.2.3
[INFO] [stderr]    Compiling serde v1.0.123
[INFO] [stderr]    Compiling string_cache_shared v0.3.0
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]     Checking new_debug_unreachable v1.0.4
[INFO] [stderr]    Compiling itoa v0.4.7
[INFO] [stderr]     Checking mac v0.1.1
[INFO] [stderr]     Checking once_cell v1.7.2
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]     Checking precomputed-hash v0.1.1
[INFO] [stderr]     Checking regex-syntax v0.6.22
[INFO] [stderr]    Compiling pulldown-cmark v0.2.0
[INFO] [stderr]     Checking percent-encoding v1.0.1
[INFO] [stderr]     Checking quick-error v1.2.3
[INFO] [stderr]     Checking maplit v1.0.2
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[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking tinyvec v1.1.1
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[INFO] [stderr]    Compiling phf_shared v0.7.24
[INFO] [stderr]     Checking thread_local v1.1.3
[INFO] [stderr]    Compiling rand_core v0.3.1
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[INFO] [stderr]     Checking humantime v1.3.0
[INFO] [stderr]    Compiling quote v1.0.9
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[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
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[INFO] [stderr]     Checking tendril v0.4.2
[INFO] [stderr]     Checking phf v0.7.24
[INFO] [stderr]     Checking quote v0.6.13
[INFO] [stderr]     Checking unicode-normalization v0.1.17
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking regex v1.4.3
[INFO] [stderr]     Checking url v1.7.2
[INFO] [stderr]    Compiling phf_generator v0.7.24
[INFO] [stderr]    Compiling string_cache_codegen v0.4.4
[INFO] [stderr]    Compiling phf_codegen v0.7.24
[INFO] [stderr]    Compiling string_cache v0.7.5
[INFO] [stderr]     Checking env_logger v0.6.2
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]     Checking version-sync v0.7.0
[INFO] [stderr]    Compiling html5ever v0.23.0
[INFO] [stderr]    Compiling markup5ever v0.8.1
[INFO] [stderr]     Checking ammonia v2.1.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:250:34
[INFO] [stdout]     |
[INFO] [stdout] 250 |     attribute_filter: Option<Box<AttributeFilter>>,
[INFO] [stdout]     |                                  ^^^^^^^^^^^^^^^ help: use `dyn`: `dyn AttributeFilter`
[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/lib.rs:2050:16
[INFO] [stdout]      |
[INFO] [stdout] 2050 |     Custom(Box<UrlRelativeEvaluate>),
[INFO] [stdout]      |                ^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn UrlRelativeEvaluate`
[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: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2078:28
[INFO] [stdout]      |
[INFO] [stdout] 2078 |     fn evaluate<'a>(&self, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                            ^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &'a str`
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(anonymous_parameters)]` on by default
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]     --> src/lib.rs:2086:21
[INFO] [stdout]      |
[INFO] [stdout] 2086 | impl fmt::Debug for AttributeFilter {
[INFO] [stdout]      |                     ^^^^^^^^^^^^^^^ help: use `dyn`: `dyn AttributeFilter`
[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: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2099:26
[INFO] [stdout]      |
[INFO] [stdout] 2099 |     fn filter<'a>(&self, &str, &str, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                          ^^^^ help: try naming the parameter or explicitly ignoring it: `_: &str`
[INFO] [stdout]      |
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2099:32
[INFO] [stdout]      |
[INFO] [stdout] 2099 |     fn filter<'a>(&self, &str, &str, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                                ^^^^ help: try naming the parameter or explicitly ignoring it: `_: &str`
[INFO] [stdout]      |
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2099:38
[INFO] [stdout]      |
[INFO] [stdout] 2099 |     fn filter<'a>(&self, &str, &str, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                                      ^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &'a str`
[INFO] [stdout]      |
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:250:34
[INFO] [stdout]     |
[INFO] [stdout] 250 |     attribute_filter: Option<Box<AttributeFilter>>,
[INFO] [stdout]     |                                  ^^^^^^^^^^^^^^^ help: use `dyn`: `dyn AttributeFilter`
[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/lib.rs:2050:16
[INFO] [stdout]      |
[INFO] [stdout] 2050 |     Custom(Box<UrlRelativeEvaluate>),
[INFO] [stdout]      |                ^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn UrlRelativeEvaluate`
[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: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2078:28
[INFO] [stdout]      |
[INFO] [stdout] 2078 |     fn evaluate<'a>(&self, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                            ^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &'a str`
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(anonymous_parameters)]` on by default
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]     --> src/lib.rs:2086:21
[INFO] [stdout]      |
[INFO] [stdout] 2086 | impl fmt::Debug for AttributeFilter {
[INFO] [stdout]      |                     ^^^^^^^^^^^^^^^ help: use `dyn`: `dyn AttributeFilter`
[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: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2099:26
[INFO] [stdout]      |
[INFO] [stdout] 2099 |     fn filter<'a>(&self, &str, &str, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                          ^^^^ help: try naming the parameter or explicitly ignoring it: `_: &str`
[INFO] [stdout]      |
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2099:32
[INFO] [stdout]      |
[INFO] [stdout] 2099 |     fn filter<'a>(&self, &str, &str, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                                ^^^^ help: try naming the parameter or explicitly ignoring it: `_: &str`
[INFO] [stdout]      |
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]     --> src/lib.rs:2099:38
[INFO] [stdout]      |
[INFO] [stdout] 2099 |     fn filter<'a>(&self, &str, &str, &'a str) -> Option<Cow<'a, str>>;
[INFO] [stdout]      |                                      ^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &'a str`
[INFO] [stdout]      |
[INFO] [stdout]      = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]      = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]     --> src/lib.rs:2381:20
[INFO] [stdout]      |
[INFO] [stdout] 2381 |                 }, value.to_string());
[INFO] [stdout]      |                    ^^^^^^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout]      = note: this usage of assert!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]      = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout] help: add a "{}" format string to Display the message
[INFO] [stdout]      |
[INFO] [stdout] 2381 |                 }, "{}", value.to_string());
[INFO] [stdout]      |                    +++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021.
[INFO] [stdout]     --> src/lib.rs:2910:28
[INFO] [stdout]      |
[INFO] [stdout] 2910 |             .rm_tags(["a"].into_iter().cloned())
[INFO] [stdout]      |                            ^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]      = warning: this changes meaning in Rust 2021
[INFO] [stdout]      = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]      |
[INFO] [stdout] 2910 |             .rm_tags(["a"].iter().cloned())
[INFO] [stdout]      |                            ~~~~
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]      |
[INFO] [stdout] 2910 |             .rm_tags(IntoIterator::into_iter(["a"]).cloned())
[INFO] [stdout]      |                      ++++++++++++++++++++++++     ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021.
[INFO] [stdout]     --> src/lib.rs:2911:58
[INFO] [stdout]      |
[INFO] [stdout] 2911 |             .rm_tag_attributes("a", ["href", "hreflang"].into_iter().cloned())
[INFO] [stdout]      |                                                          ^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = warning: this changes meaning in Rust 2021
[INFO] [stdout]      = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]      |
[INFO] [stdout] 2911 |             .rm_tag_attributes("a", ["href", "hreflang"].iter().cloned())
[INFO] [stdout]      |                                                          ~~~~
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]      |
[INFO] [stdout] 2911 |             .rm_tag_attributes("a", IntoIterator::into_iter(["href", "hreflang"]).cloned())
[INFO] [stdout]      |                                     ++++++++++++++++++++++++                    ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> examples/ammonia-cat.rs:13:22
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let mut rdr: Box<Read> = if input == "-" {
[INFO] [stdout]    |                      ^^^^ help: use `dyn`: `dyn Read`
[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]   --> examples/ammonia-cat.rs:19:22
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let mut wrt: Box<Write> = if output == "-" {
[INFO] [stdout]    |                      ^^^^^ help: use `dyn`: `dyn Write`
[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 1m 37s
[INFO] running `Command { std: "docker" "inspect" "ae036a0d73e3d7c2fa3ac865f8a120a54a2c40bf96cc86556614b05bf819faec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ae036a0d73e3d7c2fa3ac865f8a120a54a2c40bf96cc86556614b05bf819faec", kill_on_drop: false }`
[INFO] [stdout] ae036a0d73e3d7c2fa3ac865f8a120a54a2c40bf96cc86556614b05bf819faec
