[INFO] fetching crate drias 0.0.3...
[INFO] checking drias-0.0.3 against nightly-2024-02-05 for check-cfg-2
[INFO] extracting crate drias 0.0.3 into /workspace/builds/worker-1-tc1/source
[INFO] validating manifest of crates.io crate drias 0.0.3 on toolchain nightly-2024-02-05
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly-2024-02-05" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate drias 0.0.3
[INFO] finished tweaking crates.io crate drias 0.0.3
[INFO] tweaked toml for crates.io crate drias 0.0.3 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly-2024-02-05" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly-2024-02-05" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded yansi v0.5.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2024-02-05" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a4b3f08f01efc70af865c18584229f1467a0707199a1608f45fc4737dc43a7c7
[INFO] running `Command { std: "docker" "start" "-a" "a4b3f08f01efc70af865c18584229f1467a0707199a1608f45fc4737dc43a7c7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a4b3f08f01efc70af865c18584229f1467a0707199a1608f45fc4737dc43a7c7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a4b3f08f01efc70af865c18584229f1467a0707199a1608f45fc4737dc43a7c7", kill_on_drop: false }`
[INFO] [stdout] a4b3f08f01efc70af865c18584229f1467a0707199a1608f45fc4737dc43a7c7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2024-02-05" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9e5f5ed659aa446e62bcd8745d6c1193fda98cab844103393068e34abefb0170
[INFO] running `Command { std: "docker" "start" "-a" "9e5f5ed659aa446e62bcd8745d6c1193fda98cab844103393068e34abefb0170", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver v1.0.21
[INFO] [stderr]    Compiling proc-macro2 v1.0.78
[INFO] [stderr]     Checking unicode-ident v1.0.12
[INFO] [stderr]     Checking yansi v0.5.1
[INFO] [stderr]    Compiling rustc_version v0.4.0
[INFO] [stderr]    Compiling drias v0.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro2::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:23:13
[INFO] [stdout]    |
[INFO] [stdout] 23 |        *self.clone()
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(suspicious_double_ref_op)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro2::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:23:13
[INFO] [stdout]    |
[INFO] [stdout] 23 |        *self.clone()
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(suspicious_double_ref_op)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:29:25
[INFO] [stdout]    |
[INFO] [stdout] 29 |         Span::from(*self.clone())
[INFO] [stdout]    |                         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:29:25
[INFO] [stdout]    |
[INFO] [stdout] 29 |         Span::from(*self.clone())
[INFO] [stdout]    |                         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.67s
[INFO] running `Command { std: "docker" "inspect" "9e5f5ed659aa446e62bcd8745d6c1193fda98cab844103393068e34abefb0170", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9e5f5ed659aa446e62bcd8745d6c1193fda98cab844103393068e34abefb0170", kill_on_drop: false }`
[INFO] [stdout] 9e5f5ed659aa446e62bcd8745d6c1193fda98cab844103393068e34abefb0170
[INFO] checking drias-0.0.3 against nightly-2024-02-05+rustflags=-Dunexpected_cfgs+cargoflags=-Zcheck-cfg for check-cfg-2
[INFO] extracting crate drias 0.0.3 into /workspace/builds/worker-1-tc2/source
[INFO] validating manifest of crates.io crate drias 0.0.3 on toolchain nightly-2024-02-05
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly-2024-02-05" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate drias 0.0.3
[INFO] finished tweaking crates.io crate drias 0.0.3
[INFO] tweaked toml for crates.io crate drias 0.0.3 written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly-2024-02-05" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly-2024-02-05" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2024-02-05" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 98a03894f04a51582853a48c5eeeefc7f58c5ac92ebdb8194433e37114bfef92
[INFO] running `Command { std: "docker" "start" "-a" "98a03894f04a51582853a48c5eeeefc7f58c5ac92ebdb8194433e37114bfef92", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "98a03894f04a51582853a48c5eeeefc7f58c5ac92ebdb8194433e37114bfef92", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98a03894f04a51582853a48c5eeeefc7f58c5ac92ebdb8194433e37114bfef92", kill_on_drop: false }`
[INFO] [stdout] 98a03894f04a51582853a48c5eeeefc7f58c5ac92ebdb8194433e37114bfef92
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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 -Dunexpected_cfgs" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2024-02-05" "check" "--frozen" "--all" "--all-targets" "--message-format=json" "-Zcheck-cfg", kill_on_drop: false }`
[INFO] [stdout] 7d0c514ac1eb017305ec4d0dd42cc19d78e43b55ab9b44205c366c08800ae4cd
[INFO] running `Command { std: "docker" "start" "-a" "7d0c514ac1eb017305ec4d0dd42cc19d78e43b55ab9b44205c366c08800ae4cd", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver v1.0.21
[INFO] [stderr]    Compiling proc-macro2 v1.0.78
[INFO] [stderr]     Checking unicode-ident v1.0.12
[INFO] [stderr]     Checking yansi v0.5.1
[INFO] [stderr]    Compiling rustc_version v0.4.0
[INFO] [stderr]    Compiling drias v0.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]  --> src/lib.rs:1:13
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(rust_unstable, feature(proc_macro_diagnostic))]
[INFO] [stdout]   |             ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: expected names are: `debug_assertions`, `doc`, `doctest`, `feature`, `miri`, `overflow_checks`, `panic`, `proc_macro`, `relocation_model`, `sanitize`, `sanitizer_cfi_generalize_pointers`, `sanitizer_cfi_normalize_integers`, `target_abi`, `target_arch`, `target_endian`, `target_env`, `target_family`, `target_feature`, `target_has_atomic`, `target_has_atomic_equal_alignment`, `target_has_atomic_load_store`, `target_os`, `target_pointer_width`, `target_thread_local`, `target_vendor`, `test`, `unix`, `windows`
[INFO] [stdout]   = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]   = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout]   = note: requested on the command line with `-D unexpected-cfgs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]  --> src/diagnostic/mod.rs:5:7
[INFO] [stdout]   |
[INFO] [stdout] 5 | #[cfg(rust_unstable)] pub mod nightly;
[INFO] [stdout]   |       ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]   = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]   --> src/diagnostic/diagnostic.rs:53:11
[INFO] [stdout]    |
[INFO] [stdout] 53 |     #[cfg(rust_unstable)]
[INFO] [stdout]    |           ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]   --> src/diagnostic/diagnostic.rs:65:15
[INFO] [stdout]    |
[INFO] [stdout] 65 |         #[cfg(rust_unstable)]
[INFO] [stdout]    |               ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_stable`
[INFO] [stdout]   --> src/diagnostic/diagnostic.rs:67:19
[INFO] [stdout]    |
[INFO] [stdout] 67 |         #[cfg(all(rust_stable, feature="diag_emulate"))]
[INFO] [stdout]    |                   ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_stable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]   --> src/lib.rs:10:15
[INFO] [stdout]    |
[INFO] [stdout] 10 |         #[cfg(rust_unstable)] return true;
[INFO] [stdout]    |               ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]  --> src/lib.rs:1:13
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(rust_unstable, feature(proc_macro_diagnostic))]
[INFO] [stdout]   |             ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: expected names are: `debug_assertions`, `doc`, `doctest`, `feature`, `miri`, `overflow_checks`, `panic`, `proc_macro`, `relocation_model`, `sanitize`, `sanitizer_cfi_generalize_pointers`, `sanitizer_cfi_normalize_integers`, `target_abi`, `target_arch`, `target_endian`, `target_env`, `target_family`, `target_feature`, `target_has_atomic`, `target_has_atomic_equal_alignment`, `target_has_atomic_load_store`, `target_os`, `target_pointer_width`, `target_thread_local`, `target_vendor`, `test`, `unix`, `windows`
[INFO] [stdout]   = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]   = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout]   = note: requested on the command line with `-D unexpected-cfgs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]  --> src/diagnostic/mod.rs:5:7
[INFO] [stdout]   |
[INFO] [stdout] 5 | #[cfg(rust_unstable)] pub mod nightly;
[INFO] [stdout]   |       ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]   = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]   --> src/diagnostic/diagnostic.rs:53:11
[INFO] [stdout]    |
[INFO] [stdout] 53 |     #[cfg(rust_unstable)]
[INFO] [stdout]    |           ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]   --> src/diagnostic/diagnostic.rs:65:15
[INFO] [stdout]    |
[INFO] [stdout] 65 |         #[cfg(rust_unstable)]
[INFO] [stdout]    |               ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_stable`
[INFO] [stdout]   --> src/diagnostic/diagnostic.rs:67:19
[INFO] [stdout]    |
[INFO] [stdout] 67 |         #[cfg(all(rust_stable, feature="diag_emulate"))]
[INFO] [stdout]    |                   ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_stable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unexpected `cfg` condition name: `rust_unstable`
[INFO] [stdout]   --> src/lib.rs:10:15
[INFO] [stdout]    |
[INFO] [stdout] 10 |         #[cfg(rust_unstable)] return true;
[INFO] [stdout]    |               ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider using a Cargo feature instead or adding `println!("cargo:rustc-check-cfg=cfg(rust_unstable)");` to the top of a `build.rs`
[INFO] [stdout]    = note: see <https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#check-cfg> for more information about checking conditional configuration
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro2::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:23:13
[INFO] [stdout]    |
[INFO] [stdout] 23 |        *self.clone()
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(suspicious_double_ref_op)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:29:25
[INFO] [stdout]    |
[INFO] [stdout] 29 |         Span::from(*self.clone())
[INFO] [stdout]    |                         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro2::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:23:13
[INFO] [stdout]    |
[INFO] [stdout] 23 |        *self.clone()
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(suspicious_double_ref_op)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: using `.clone()` on a double reference, which returns `&proc_macro::Span` instead of cloning the inner type
[INFO] [stdout]   --> src/span/span.rs:29:25
[INFO] [stdout]    |
[INFO] [stdout] 29 |         Span::from(*self.clone())
[INFO] [stdout]    |                         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 previous errors; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 previous errors; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `drias` (lib) due to 7 previous errors; 2 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `drias` (lib test) due to 7 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "7d0c514ac1eb017305ec4d0dd42cc19d78e43b55ab9b44205c366c08800ae4cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d0c514ac1eb017305ec4d0dd42cc19d78e43b55ab9b44205c366c08800ae4cd", kill_on_drop: false }`
[INFO] [stdout] 7d0c514ac1eb017305ec4d0dd42cc19d78e43b55ab9b44205c366c08800ae4cd
