[INFO] fetching crate peek-again 0.5.2...
[INFO] testing peek-again-0.5.2 against try#b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b for pr-145330-1
[INFO] extracting crate peek-again 0.5.2 into /workspace/builds/worker-4-tc2/source
[INFO] removed /workspace/builds/worker-4-tc2/source/rust-toolchain.toml
[INFO] started tweaking crates.io crate peek-again 0.5.2
[INFO] finished tweaking crates.io crate peek-again 0.5.2
[INFO] tweaked toml for crates.io crate peek-again 0.5.2 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate peek-again 0.5.2 on toolchain b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 39 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f7503d278a50a754cf44cb787dd3a0a07ba104623e3747e68bad880c7f48ef5f
[INFO] running `Command { std: "docker" "start" "-a" "f7503d278a50a754cf44cb787dd3a0a07ba104623e3747e68bad880c7f48ef5f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f7503d278a50a754cf44cb787dd3a0a07ba104623e3747e68bad880c7f48ef5f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f7503d278a50a754cf44cb787dd3a0a07ba104623e3747e68bad880c7f48ef5f", kill_on_drop: false }`
[INFO] [stdout] f7503d278a50a754cf44cb787dd3a0a07ba104623e3747e68bad880c7f48ef5f
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3e803c5206079008a17bc6764b7e736f5cea48a3ee190bb725f761a29c1fceca
[INFO] running `Command { std: "docker" "start" "-a" "3e803c5206079008a17bc6764b7e736f5cea48a3ee190bb725f761a29c1fceca", kill_on_drop: false }`
[INFO] [stderr]    Compiling peek-again v0.5.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]  --> src/lib.rs:4:17
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![cfg_attr(not(kani), deny(missing_docs))]
[INFO] [stdout]   |                 ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: expected names are: `docsrs`, `feature`, and `test` and 31 more
[INFO] [stdout]   = help: consider using a Cargo feature instead
[INFO] [stdout]   = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]            [lints.rust]
[INFO] [stdout]            unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]   = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout]   = note: requested on the command line with `-W unexpected-cfgs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:16:7
[INFO] [stdout]    |
[INFO] [stdout] 16 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:19:7
[INFO] [stdout]    |
[INFO] [stdout] 19 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:32:11
[INFO] [stdout]    |
[INFO] [stdout] 32 | #[cfg(not(kani))]
[INFO] [stdout]    |           ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:39:7
[INFO] [stdout]    |
[INFO] [stdout] 39 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:422:7
[INFO] [stdout]     |
[INFO] [stdout] 422 | #[cfg(kani)]
[INFO] [stdout]     |       ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:2304:11
[INFO] [stdout]      |
[INFO] [stdout] 2304 | #[cfg(all(kani, test))]
[INFO] [stdout]      |           ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:152:15
[INFO] [stdout]     |
[INFO] [stdout] 152 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:160:11
[INFO] [stdout]     |
[INFO] [stdout] 160 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:216:42
[INFO] [stdout]     |
[INFO] [stdout] 216 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stdout]     |                                          ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:458:42
[INFO] [stdout]     |
[INFO] [stdout] 458 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stdout]     |                                          ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:499:15
[INFO] [stdout]     |
[INFO] [stdout] 499 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:506:11
[INFO] [stdout]     |
[INFO] [stdout] 506 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:878:11
[INFO] [stdout]     |
[INFO] [stdout] 878 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:897:15
[INFO] [stdout]     |
[INFO] [stdout] 897 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:541:15
[INFO] [stdout]     |
[INFO] [stdout] 541 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:568:15
[INFO] [stdout]     |
[INFO] [stdout] 568 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:571:15
[INFO] [stdout]     |
[INFO] [stdout] 571 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:607:15
[INFO] [stdout]     |
[INFO] [stdout] 607 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:610:15
[INFO] [stdout]     |
[INFO] [stdout] 610 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:670:15
[INFO] [stdout]     |
[INFO] [stdout] 670 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:713:15
[INFO] [stdout]     |
[INFO] [stdout] 713 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:716:15
[INFO] [stdout]     |
[INFO] [stdout] 716 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:767:15
[INFO] [stdout]     |
[INFO] [stdout] 767 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:770:15
[INFO] [stdout]     |
[INFO] [stdout] 770 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:815:15
[INFO] [stdout]     |
[INFO] [stdout] 815 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:818:15
[INFO] [stdout]     |
[INFO] [stdout] 818 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:846:15
[INFO] [stdout]     |
[INFO] [stdout] 846 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:929:15
[INFO] [stdout]     |
[INFO] [stdout] 929 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:932:15
[INFO] [stdout]     |
[INFO] [stdout] 932 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1143:15
[INFO] [stdout]      |
[INFO] [stdout] 1143 |         #[cfg(kani)]
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1145:15
[INFO] [stdout]      |
[INFO] [stdout] 1145 |         #[cfg(kani)] { kani::assert(num_peeked != 0, "Precondition violated, state must not be empty"); }
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1149:15
[INFO] [stdout]      |
[INFO] [stdout] 1149 |         #[cfg(kani)] {
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1170:15
[INFO] [stdout]      |
[INFO] [stdout] 1170 |         #[cfg(kani)] {
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.16s
[INFO] running `Command { std: "docker" "inspect" "3e803c5206079008a17bc6764b7e736f5cea48a3ee190bb725f761a29c1fceca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3e803c5206079008a17bc6764b7e736f5cea48a3ee190bb725f761a29c1fceca", kill_on_drop: false }`
[INFO] [stdout] 3e803c5206079008a17bc6764b7e736f5cea48a3ee190bb725f761a29c1fceca
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d3c580815b7b616e8f3bd86de9abdf486bc392c86bffbe67925b5bae448e1c4c
[INFO] running `Command { std: "docker" "start" "-a" "d3c580815b7b616e8f3bd86de9abdf486bc392c86bffbe67925b5bae448e1c4c", kill_on_drop: false }`
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]  --> src/lib.rs:4:17
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![cfg_attr(not(kani), deny(missing_docs))]
[INFO] [stdout]   |                 ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: expected names are: `docsrs`, `feature`, and `test` and 31 more
[INFO] [stdout]   = help: consider using a Cargo feature instead
[INFO] [stdout]   = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]            [lints.rust]
[INFO] [stdout]            unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]   = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout]   = note: requested on the command line with `-W unexpected-cfgs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:16:7
[INFO] [stdout]    |
[INFO] [stdout] 16 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:19:7
[INFO] [stdout]    |
[INFO] [stdout] 19 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:32:11
[INFO] [stdout]    |
[INFO] [stdout] 32 | #[cfg(not(kani))]
[INFO] [stdout]    |           ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:39:7
[INFO] [stdout]    |
[INFO] [stdout] 39 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:422:7
[INFO] [stdout]     |
[INFO] [stdout] 422 | #[cfg(kani)]
[INFO] [stdout]     |       ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:2304:11
[INFO] [stdout]      |
[INFO] [stdout] 2304 | #[cfg(all(kani, test))]
[INFO] [stdout]      |           ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:152:15
[INFO] [stdout]     |
[INFO] [stdout] 152 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:160:11
[INFO] [stdout]     |
[INFO] [stdout] 160 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:216:42
[INFO] [stdout]     |
[INFO] [stdout] 216 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stdout]     |                                          ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:458:42
[INFO] [stdout]     |
[INFO] [stdout] 458 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stdout]     |                                          ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:499:15
[INFO] [stdout]     |
[INFO] [stdout] 499 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:506:11
[INFO] [stdout]     |
[INFO] [stdout] 506 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:878:11
[INFO] [stdout]     |
[INFO] [stdout] 878 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:897:15
[INFO] [stdout]     |
[INFO] [stdout] 897 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:541:15
[INFO] [stdout]     |
[INFO] [stdout] 541 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:568:15
[INFO] [stdout]     |
[INFO] [stdout] 568 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:571:15
[INFO] [stdout]     |
[INFO] [stdout] 571 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:607:15
[INFO] [stdout]     |
[INFO] [stdout] 607 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:610:15
[INFO] [stdout]     |
[INFO] [stdout] 610 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:670:15
[INFO] [stdout]     |
[INFO] [stdout] 670 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:713:15
[INFO] [stdout]     |
[INFO] [stdout] 713 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:716:15
[INFO] [stdout]     |
[INFO] [stdout] 716 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:767:15
[INFO] [stdout]     |
[INFO] [stdout] 767 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:770:15
[INFO] [stdout]     |
[INFO] [stdout] 770 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:815:15
[INFO] [stdout]     |
[INFO] [stdout] 815 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:818:15
[INFO] [stdout]     |
[INFO] [stdout] 818 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling num-traits v0.2.19
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:846:15
[INFO] [stdout]     |
[INFO] [stdout] 846 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:929:15
[INFO] [stdout]     |
[INFO] [stdout] 929 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:932:15
[INFO] [stdout]     |
[INFO] [stdout] 932 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1143:15
[INFO] [stdout]      |
[INFO] [stdout] 1143 |         #[cfg(kani)]
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1145:15
[INFO] [stdout]      |
[INFO] [stdout] 1145 |         #[cfg(kani)] { kani::assert(num_peeked != 0, "Precondition violated, state must not be empty"); }
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling wait-timeout v0.2.1
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1149:15
[INFO] [stdout]      |
[INFO] [stdout] 1149 |         #[cfg(kani)] {
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling tempfile v3.23.0
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1170:15
[INFO] [stdout]      |
[INFO] [stdout] 1170 |         #[cfg(kani)] {
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rand_chacha v0.9.0
[INFO] [stderr]    Compiling rand v0.9.2
[INFO] [stderr]    Compiling rand_xorshift v0.4.0
[INFO] [stderr]    Compiling rusty-fork v0.3.0
[INFO] [stderr]    Compiling proptest v1.8.0
[INFO] [stderr]    Compiling peek-again v0.5.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]  --> src/lib.rs:4:17
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![cfg_attr(not(kani), deny(missing_docs))]
[INFO] [stdout]   |                 ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: expected names are: `docsrs`, `feature`, and `test` and 31 more
[INFO] [stdout]   = help: consider using a Cargo feature instead
[INFO] [stdout]   = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]            [lints.rust]
[INFO] [stdout]            unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]   = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout]   = note: requested on the command line with `-W unexpected-cfgs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:16:7
[INFO] [stdout]    |
[INFO] [stdout] 16 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:19:7
[INFO] [stdout]    |
[INFO] [stdout] 19 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:32:11
[INFO] [stdout]    |
[INFO] [stdout] 32 | #[cfg(not(kani))]
[INFO] [stdout]    |           ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]   --> src/lib.rs:39:7
[INFO] [stdout]    |
[INFO] [stdout] 39 | #[cfg(kani)]
[INFO] [stdout]    |       ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead
[INFO] [stdout]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]             [lints.rust]
[INFO] [stdout]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:422:7
[INFO] [stdout]     |
[INFO] [stdout] 422 | #[cfg(kani)]
[INFO] [stdout]     |       ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:2304:11
[INFO] [stdout]      |
[INFO] [stdout] 2304 | #[cfg(all(kani, test))]
[INFO] [stdout]      |           ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:152:15
[INFO] [stdout]     |
[INFO] [stdout] 152 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:160:11
[INFO] [stdout]     |
[INFO] [stdout] 160 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:216:42
[INFO] [stdout]     |
[INFO] [stdout] 216 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stdout]     |                                          ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:458:42
[INFO] [stdout]     |
[INFO] [stdout] 458 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stdout]     |                                          ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:499:15
[INFO] [stdout]     |
[INFO] [stdout] 499 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:506:11
[INFO] [stdout]     |
[INFO] [stdout] 506 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:878:11
[INFO] [stdout]     |
[INFO] [stdout] 878 |     #[cfg(kani)]
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:897:15
[INFO] [stdout]     |
[INFO] [stdout] 897 |     #[cfg(not(kani))]
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:541:15
[INFO] [stdout]     |
[INFO] [stdout] 541 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:568:15
[INFO] [stdout]     |
[INFO] [stdout] 568 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:571:15
[INFO] [stdout]     |
[INFO] [stdout] 571 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:607:15
[INFO] [stdout]     |
[INFO] [stdout] 607 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:610:15
[INFO] [stdout]     |
[INFO] [stdout] 610 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:670:15
[INFO] [stdout]     |
[INFO] [stdout] 670 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:713:15
[INFO] [stdout]     |
[INFO] [stdout] 713 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:716:15
[INFO] [stdout]     |
[INFO] [stdout] 716 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:767:15
[INFO] [stdout]     |
[INFO] [stdout] 767 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:770:15
[INFO] [stdout]     |
[INFO] [stdout] 770 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:815:15
[INFO] [stdout]     |
[INFO] [stdout] 815 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:818:15
[INFO] [stdout]     |
[INFO] [stdout] 818 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:846:15
[INFO] [stdout]     |
[INFO] [stdout] 846 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:929:15
[INFO] [stdout]     |
[INFO] [stdout] 929 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]    --> src/lib.rs:932:15
[INFO] [stdout]     |
[INFO] [stdout] 932 |         #[cfg(kani)] {
[INFO] [stdout]     |               ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider using a Cargo feature instead
[INFO] [stdout]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]              [lints.rust]
[INFO] [stdout]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1143:15
[INFO] [stdout]      |
[INFO] [stdout] 1143 |         #[cfg(kani)]
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1145:15
[INFO] [stdout]      |
[INFO] [stdout] 1145 |         #[cfg(kani)] { kani::assert(num_peeked != 0, "Precondition violated, state must not be empty"); }
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1149:15
[INFO] [stdout]      |
[INFO] [stdout] 1149 |         #[cfg(kani)] {
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unexpected `cfg` condition name: `kani`
[INFO] [stdout]     --> src/lib.rs:1170:15
[INFO] [stdout]      |
[INFO] [stdout] 1170 |         #[cfg(kani)] {
[INFO] [stdout]      |               ^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: consider using a Cargo feature instead
[INFO] [stdout]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stdout]               [lints.rust]
[INFO] [stdout]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stdout]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stdout]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `format`
[INFO] [stdout]     --> src/lib.rs:1773:17
[INFO] [stdout]      |
[INFO] [stdout] 1773 |     use alloc::{format, vec::Vec};
[INFO] [stdout]      |                 ^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 6.46s
[INFO] running `Command { std: "docker" "inspect" "d3c580815b7b616e8f3bd86de9abdf486bc392c86bffbe67925b5bae448e1c4c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d3c580815b7b616e8f3bd86de9abdf486bc392c86bffbe67925b5bae448e1c4c", kill_on_drop: false }`
[INFO] [stdout] d3c580815b7b616e8f3bd86de9abdf486bc392c86bffbe67925b5bae448e1c4c
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] bd031a14d5e2cd4f99b0b79ba4be888bf8de39485f5f0efe748d9ac45f1f9bb6
[INFO] running `Command { std: "docker" "start" "-a" "bd031a14d5e2cd4f99b0b79ba4be888bf8de39485f5f0efe748d9ac45f1f9bb6", kill_on_drop: false }`
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]  --> src/lib.rs:4:17
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![cfg_attr(not(kani), deny(missing_docs))]
[INFO] [stderr]   |                 ^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = help: expected names are: `docsrs`, `feature`, and `test` and 31 more
[INFO] [stderr]   = help: consider using a Cargo feature instead
[INFO] [stderr]   = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]            [lints.rust]
[INFO] [stderr]            unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]   = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr]   = note: requested on the command line with `-W unexpected-cfgs`
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]   --> src/lib.rs:16:7
[INFO] [stderr]    |
[INFO] [stderr] 16 | #[cfg(kani)]
[INFO] [stderr]    |       ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider using a Cargo feature instead
[INFO] [stderr]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]             [lints.rust]
[INFO] [stderr]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]   --> src/lib.rs:19:7
[INFO] [stderr]    |
[INFO] [stderr] 19 | #[cfg(kani)]
[INFO] [stderr]    |       ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider using a Cargo feature instead
[INFO] [stderr]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]             [lints.rust]
[INFO] [stderr]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]   --> src/lib.rs:32:11
[INFO] [stderr]    |
[INFO] [stderr] 32 | #[cfg(not(kani))]
[INFO] [stderr]    |           ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider using a Cargo feature instead
[INFO] [stderr]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]             [lints.rust]
[INFO] [stderr]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]   --> src/lib.rs:39:7
[INFO] [stderr]    |
[INFO] [stderr] 39 | #[cfg(kani)]
[INFO] [stderr]    |       ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider using a Cargo feature instead
[INFO] [stderr]    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]             [lints.rust]
[INFO] [stderr]             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:422:7
[INFO] [stderr]     |
[INFO] [stderr] 422 | #[cfg(kani)]
[INFO] [stderr]     |       ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]     --> src/lib.rs:2304:11
[INFO] [stderr]      |
[INFO] [stderr] 2304 | #[cfg(all(kani, test))]
[INFO] [stderr]      |           ^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = help: consider using a Cargo feature instead
[INFO] [stderr]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]               [lints.rust]
[INFO] [stderr]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:152:15
[INFO] [stderr]     |
[INFO] [stderr] 152 |     #[cfg(not(kani))]
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:160:11
[INFO] [stderr]     |
[INFO] [stderr] 160 |     #[cfg(kani)]
[INFO] [stderr]     |           ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:216:42
[INFO] [stderr]     |
[INFO] [stderr] 216 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stderr]     |                                          ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:458:42
[INFO] [stderr]     |
[INFO] [stderr] 458 |     #[cfg_attr(all(debug_assertions, not(kani)), track_caller)]
[INFO] [stderr]     |                                          ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:499:15
[INFO] [stderr]     |
[INFO] [stderr] 499 |     #[cfg(not(kani))]
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:506:11
[INFO] [stderr]     |
[INFO] [stderr] 506 |     #[cfg(kani)]
[INFO] [stderr]     |           ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:878:11
[INFO] [stderr]     |
[INFO] [stderr] 878 |     #[cfg(kani)]
[INFO] [stderr]     |           ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:897:15
[INFO] [stderr]     |
[INFO] [stderr] 897 |     #[cfg(not(kani))]
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:541:15
[INFO] [stderr]     |
[INFO] [stderr] 541 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:568:15
[INFO] [stderr]     |
[INFO] [stderr] 568 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:571:15
[INFO] [stderr]     |
[INFO] [stderr] 571 |         #[cfg(kani)] {
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:607:15
[INFO] [stderr]     |
[INFO] [stderr] 607 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:610:15
[INFO] [stderr]     |
[INFO] [stderr] 610 |         #[cfg(kani)] {
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:670:15
[INFO] [stderr]     |
[INFO] [stderr] 670 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:713:15
[INFO] [stderr]     |
[INFO] [stderr] 713 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:716:15
[INFO] [stderr]     |
[INFO] [stderr] 716 |         #[cfg(kani)] {
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:767:15
[INFO] [stderr]     |
[INFO] [stderr] 767 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:770:15
[INFO] [stderr]     |
[INFO] [stderr] 770 |         #[cfg(kani)] {
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:815:15
[INFO] [stderr]     |
[INFO] [stderr] 815 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:818:15
[INFO] [stderr]     |
[INFO] [stderr] 818 |         #[cfg(kani)] {
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:846:15
[INFO] [stderr]     |
[INFO] [stderr] 846 |         #[cfg(kani)] {
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:929:15
[INFO] [stderr]     |
[INFO] [stderr] 929 |         #[cfg(kani)] { kani::assert(self.is_safe(), "`Peek` invariant violated, state must be non-empty`"); }
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]    --> src/lib.rs:932:15
[INFO] [stderr]     |
[INFO] [stderr] 932 |         #[cfg(kani)] {
[INFO] [stderr]     |               ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: consider using a Cargo feature instead
[INFO] [stderr]     = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]              [lints.rust]
[INFO] [stderr]              unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]     = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]     = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]     --> src/lib.rs:1143:15
[INFO] [stderr]      |
[INFO] [stderr] 1143 |         #[cfg(kani)]
[INFO] [stderr]      |               ^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = help: consider using a Cargo feature instead
[INFO] [stderr]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]               [lints.rust]
[INFO] [stderr]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]     --> src/lib.rs:1145:15
[INFO] [stderr]      |
[INFO] [stderr] 1145 |         #[cfg(kani)] { kani::assert(num_peeked != 0, "Precondition violated, state must not be empty"); }
[INFO] [stderr]      |               ^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = help: consider using a Cargo feature instead
[INFO] [stderr]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]               [lints.rust]
[INFO] [stderr]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]     --> src/lib.rs:1149:15
[INFO] [stderr]      |
[INFO] [stderr] 1149 |         #[cfg(kani)] {
[INFO] [stderr]      |               ^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = help: consider using a Cargo feature instead
[INFO] [stderr]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]               [lints.rust]
[INFO] [stderr]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: unexpected `cfg` condition name: `kani`
[INFO] [stderr]     --> src/lib.rs:1170:15
[INFO] [stderr]      |
[INFO] [stderr] 1170 |         #[cfg(kani)] {
[INFO] [stderr]      |               ^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = help: consider using a Cargo feature instead
[INFO] [stderr]      = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
[INFO] [stderr]               [lints.rust]
[INFO] [stderr]               unexpected_cfgs = { level = "warn", check-cfg = ['cfg(kani)'] }
[INFO] [stderr]      = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(kani)");` to the top of the `build.rs`
[INFO] [stderr]      = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
[INFO] [stderr] 
[INFO] [stderr] warning: `peek-again` (lib) generated 34 warnings
[INFO] [stderr] warning: unused import: `format`
[INFO] [stderr]     --> src/lib.rs:1773:17
[INFO] [stderr]      |
[INFO] [stderr] 1773 |     use alloc::{format, vec::Vec};
[INFO] [stderr]      |                 ^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `peek-again` (lib test) generated 35 warnings (34 duplicates) (run `cargo fix --lib -p peek-again --tests` to apply 1 suggestion)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/peek_again-80c4cab5b4d2aa83)
[INFO] [stdout] 
[INFO] [stdout] running 42 tests
[INFO] [stdout] test tests::drain_if_both_full_smoke ... ok
[INFO] [stdout] test tests::drain_if_both_empty ... ok
[INFO] [stdout] test tests::drain_if_both_missing_elem ... ok
[INFO] [stdout] test tests::find_map_peek_2_drain ... ok
[INFO] [stdout] test tests::is_both_missing_elem ... ok
[INFO] [stdout] test tests::is_both_full_smoke ... ok
[INFO] [stdout] test tests::exact_size_len ... ok
[INFO] [stdout] test tests::exact_size_len_peeked_2 ... ok
[INFO] [stdout] test tests::exact_size_len_peeked ... ok
[INFO] [stdout] test tests::iter_all_peeked_2 ... ok
[INFO] [stdout] test tests::iter_any_peeked ... ok
[INFO] [stdout] test tests::iter_any ... ok
[INFO] [stdout] test tests::iter_find_many ... ok
[INFO] [stdout] test tests::iter_find ... ok
[INFO] [stdout] test tests::iter_all ... ok
[INFO] [stdout] test tests::iter_all_peeked ... ok
[INFO] [stdout] test tests::iter_find_many_peeked_2 ... ok
[INFO] [stdout] test tests::iter_find_many_peeked ... ok
[INFO] [stdout] test tests::iter_any_peeked_2 ... ok
[INFO] [stdout] test tests::iter_find_map_many ... ok
[INFO] [stdout] test tests::iter_find_map ... ok
[INFO] [stdout] test tests::iter_find_map_peeked ... ok
[INFO] [stdout] test tests::iter_last_peeked ... ok
[INFO] [stdout] test tests::iter_nth_peeked_2 ... ok
[INFO] [stdout] test tests::iter_find_map_many_peeked ... ok
[INFO] [stdout] test tests::iter_last ... ok
[INFO] [stdout] test tests::iter_nth ... ok
[INFO] [stdout] test tests::iter_find_with_peeked ... ok
[INFO] [stdout] test tests::iter_find_with_peeked_2 ... ok
[INFO] [stdout] test tests::iter_find_map_peeked_2 ... ok
[INFO] [stdout] test tests::iter_nth_peeked ... ok
[INFO] [stdout] test tests::iter_find_map_many_peeked_2 ... ok
[INFO] [stdout] test tests::iter_last_peeked_2 ... ok
[INFO] [stdout] test tests::iter_next_back ... ok
[INFO] [stdout] test tests::iter_position ... ok
[INFO] [stdout] test tests::iter_next_back_peeked ... ok
[INFO] [stdout] test tests::iter_next_back_peeked_2 ... ok
[INFO] [stdout] test tests::iter_position_peeked_2 ... ok
[INFO] [stdout] test tests::iter_position_peeked ... ok
[INFO] [stdout] test tests::iter_rfind_peeked ... ok
[INFO] [stdout] test tests::iter_rfind ... ok
[INFO] [stdout] test tests::iter_rfind_peeked_2 ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 42 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 12.95s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests peek_again
[INFO] [stdout] 
[INFO] [stdout] running 23 tests
[INFO] [stdout] test src/lib.rs - (line 56) ... ok
[INFO] [stdout] test src/lib.rs - Peek<'r,T>::is_both (line 794) ... ok
[INFO] [stdout] test src/lib.rs - PeekState<'r,T>::num_peeked (line 1004) ... ok
[INFO] [stdout] test src/lib.rs - Peek<'r,T>::consume (line 650) ... ok
[INFO] [stdout] test src/lib.rs - Peek<'r,T>::peek (line 554) ... ok
[INFO] [stdout] test src/lib.rs - Peek (line 400) ... ok
[INFO] [stdout] test src/lib.rs - Peek<'r,T>::drain_if (line 691) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::from (line 1076) ... ok
[INFO] [stdout] test src/lib.rs - (line 20) ... ok
[INFO] [stdout] test src/lib.rs - (line 36) ... ok
[INFO] [stdout] test src/lib.rs - Peek<'r,T>::peek_mut (line 594) ... ok
[INFO] [stdout] test src/lib.rs - Peek<'r,T>::drain_if_both (line 747) ... ok
[INFO] [stdout] test src/lib.rs - Peekable (line 1038) ... ok
[INFO] [stdout] test src/lib.rs - Peek (line 361) ... ok
[INFO] [stdout] test src/lib.rs - Peek<'r,T>::take_next_if (line 909) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::fmt (line 1410) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::next_if_eq (line 1381) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::peek (line 1188) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::peek_2 (line 1230) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::next_if (line 1303) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::next_if_eq (line 1369) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::peek_2_mut (line 1264) ... ok
[INFO] [stdout] test src/lib.rs - Peekable<T>::peek_state (line 1110) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 23 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.44s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "bd031a14d5e2cd4f99b0b79ba4be888bf8de39485f5f0efe748d9ac45f1f9bb6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bd031a14d5e2cd4f99b0b79ba4be888bf8de39485f5f0efe748d9ac45f1f9bb6", kill_on_drop: false }`
[INFO] [stdout] bd031a14d5e2cd4f99b0b79ba4be888bf8de39485f5f0efe748d9ac45f1f9bb6