[INFO] fetching crate synstructure_test_traits 0.1.0...
[INFO] testing synstructure_test_traits-0.1.0 against try#ecabaf78506b7a4668d42dc20268c086b93f0fad for pr-87041
[INFO] extracting crate synstructure_test_traits 0.1.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate synstructure_test_traits 0.1.0 on toolchain ecabaf78506b7a4668d42dc20268c086b93f0fad
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ecabaf78506b7a4668d42dc20268c086b93f0fad" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate synstructure_test_traits 0.1.0
[INFO] finished tweaking crates.io crate synstructure_test_traits 0.1.0
[INFO] tweaked toml for crates.io crate synstructure_test_traits 0.1.0 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ecabaf78506b7a4668d42dc20268c086b93f0fad" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ecabaf78506b7a4668d42dc20268c086b93f0fad" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+ecabaf78506b7a4668d42dc20268c086b93f0fad" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b100453514fea21e408621ababa3848c8b8b10c5cf3dd957274964e583e363db
[INFO] running `Command { std: "docker" "start" "-a" "b100453514fea21e408621ababa3848c8b8b10c5cf3dd957274964e583e363db", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b100453514fea21e408621ababa3848c8b8b10c5cf3dd957274964e583e363db", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b100453514fea21e408621ababa3848c8b8b10c5cf3dd957274964e583e363db", kill_on_drop: false }`
[INFO] [stdout] b100453514fea21e408621ababa3848c8b8b10c5cf3dd957274964e583e363db
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+ecabaf78506b7a4668d42dc20268c086b93f0fad" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9a909ab683f1aa0609e12fab3464e979b0d1c9d9dadce6db384ec54aa7218bcb
[INFO] running `Command { std: "docker" "start" "-a" "9a909ab683f1aa0609e12fab3464e979b0d1c9d9dadce6db384ec54aa7218bcb", kill_on_drop: false }`
[INFO] [stderr]    Compiling synstructure_test_traits v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> lib.rs:7:38
[INFO] [stdout]   |
[INFO] [stdout] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> lib.rs:7:45
[INFO] [stdout]   |
[INFO] [stdout] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stdout]   |                                             ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> lib.rs:10:39
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stdout]    |                                       ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> lib.rs:10:46
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stdout]    |                                              ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.08s
[INFO] running `Command { std: "docker" "inspect" "9a909ab683f1aa0609e12fab3464e979b0d1c9d9dadce6db384ec54aa7218bcb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9a909ab683f1aa0609e12fab3464e979b0d1c9d9dadce6db384ec54aa7218bcb", kill_on_drop: false }`
[INFO] [stdout] 9a909ab683f1aa0609e12fab3464e979b0d1c9d9dadce6db384ec54aa7218bcb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+ecabaf78506b7a4668d42dc20268c086b93f0fad" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 51272a0e8083c783b5010a648fa9310ade424ae20f270ffd59701e85a4ca3501
[INFO] running `Command { std: "docker" "start" "-a" "51272a0e8083c783b5010a648fa9310ade424ae20f270ffd59701e85a4ca3501", kill_on_drop: false }`
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> lib.rs:7:38
[INFO] [stdout]   |
[INFO] [stdout] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling synstructure_test_traits v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> lib.rs:7:45
[INFO] [stdout]   |
[INFO] [stdout] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stdout]   |                                             ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> lib.rs:10:39
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stdout]    |                                       ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> lib.rs:10:46
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stdout]    |                                              ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> lib.rs:7:38
[INFO] [stdout]   |
[INFO] [stdout] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> lib.rs:7:45
[INFO] [stdout]   |
[INFO] [stdout] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stdout]   |                                             ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> lib.rs:10:39
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stdout]    |                                       ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> lib.rs:10:46
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stdout]    |                                              ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[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 issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.37s
[INFO] running `Command { std: "docker" "inspect" "51272a0e8083c783b5010a648fa9310ade424ae20f270ffd59701e85a4ca3501", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "51272a0e8083c783b5010a648fa9310ade424ae20f270ffd59701e85a4ca3501", kill_on_drop: false }`
[INFO] [stdout] 51272a0e8083c783b5010a648fa9310ade424ae20f270ffd59701e85a4ca3501
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+ecabaf78506b7a4668d42dc20268c086b93f0fad" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 7d8bdad32cba3d2fef0e71c4d273ee75093aa55d0c888a3bb859c83398b378ac
[INFO] running `Command { std: "docker" "start" "-a" "7d8bdad32cba3d2fef0e71c4d273ee75093aa55d0c888a3bb859c83398b378ac", kill_on_drop: false }`
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]  --> lib.rs:7:38
[INFO] [stderr]   |
[INFO] [stderr] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stderr]   |                                      ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]  --> lib.rs:7:45
[INFO] [stderr]   |
[INFO] [stderr] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stderr]   |                                             ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[INFO] [stderr]   |
[INFO] [stderr]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> lib.rs:10:39
[INFO] [stderr]    |
[INFO] [stderr] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stderr]    |                                       ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> lib.rs:10:46
[INFO] [stderr]    |
[INFO] [stderr] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stderr]    |                                              ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]  --> lib.rs:7:38
[INFO] [stderr]   |
[INFO] [stderr] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stderr]   |                                      ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]  --> lib.rs:7:45
[INFO] [stderr]   |
[INFO] [stderr] 7 |     fn walk_fields(&self, walk: &mut FnMut(&WalkFields));
[INFO] [stderr]   |                                             ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[INFO] [stderr]   |
[INFO] [stderr]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> lib.rs:10:39
[INFO] [stderr]    |
[INFO] [stderr] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stderr]    |                                       ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn FnMut(&WalkFields)`
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> lib.rs:10:46
[INFO] [stderr]    |
[INFO] [stderr] 10 |     fn walk_fields(&self, _walk: &mut FnMut(&WalkFields)) {}
[INFO] [stderr]    |                                              ^^^^^^^^^^ help: use `dyn`: `dyn WalkFields`
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/synstructure_test_traits-95192c308fcc3480)
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests synstructure_test_traits
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "7d8bdad32cba3d2fef0e71c4d273ee75093aa55d0c888a3bb859c83398b378ac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d8bdad32cba3d2fef0e71c4d273ee75093aa55d0c888a3bb859c83398b378ac", kill_on_drop: false }`
[INFO] [stdout] 7d8bdad32cba3d2fef0e71c4d273ee75093aa55d0c888a3bb859c83398b378ac