tests/ui/conditional-compilation/cfg-attr-empty-is-unused.rs


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// Check that `#[cfg_attr($PREDICATE,)]` triggers the `unused_attribute` lint.

#![deny(unused)]

#[cfg_attr(FALSE,)] //~ ERROR `#[cfg_attr]` does not expand to any attributes
fn _f() {}

#[cfg_attr(not(FALSE),)] //~ ERROR `#[cfg_attr]` does not expand to any attributes
fn _g() {}

fn main() {}