UNREACHABLE_CFG_SELECT_PREDICATES in rustc_lint::builtin - Rust
Description: The `unreachable_cfg_select_predicates` lint detects unreachable configuration predicates in the `cfg_select!` macro.

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## UNREACHABLE_CFG_SELECT_PREDICATES

# Static UNREACHABLE_CFG_SELECT_PREDICATES

Source

    pub static UNREACHABLE_CFG_SELECT_PREDICATES: &'static Lint

Expand description

The `unreachable_cfg_select_predicates` lint detects unreachable configuration predicates in the `cfg_select!` macro.

#### §Example

    cfg_select! {
        _ => (),
        windows => (),
    }

{{produces}}

#### §Explanation

This usually indicates a mistake in how the predicates are specified or ordered. In this example, the `_` predicate will always match, so the `windows` is impossible to reach. Remember, arms match in order, you probably wanted to put the `windows` case above the `_` case.