Static rustc_lint_defs::builtin::UNEXPECTED_CFGS

pub static UNEXPECTED_CFGS: &Lint

The unexpected_cfgs lint detects unexpected conditional compilation conditions.

Example

rustc --check-cfg 'cfg()'

#[cfg(widnows)]
fn foo() {}

This will produce:

warning: unexpected `cfg` condition name: `widnows`
 --> lint_example.rs:1:7
  |
1 | #[cfg(widnows)]
  |       ^^^^^^^
  |
  = note: `#[warn(unexpected_cfgs)]` on by default

Explanation

This lint is only active when --check-cfg arguments are being passed to the compiler and triggers whenever an unexpected condition name or value is used.

See the Checking Conditional Configurations section for more details.

See the Cargo Specifics section for configuring this lint in Cargo.toml.