std::mem::unreachable - Rust
Description: API documentation for the Rust `unreachable` fn in crate `std`.
Keywords: rust, rustlang, rust-lang, unreachable

# Function std::mem::unreachable [−] [src]

    pub unsafe fn unreachable() -> !

🔬 This is a nightly-only experimental API. (`unreachable` #43751)

Tells LLVM that this point in the code is not reachable, enabling further optimizations.

NB: This is very different from the `unreachable!()` macro: Unlike the macro, which panics when it is executed, it is undefined behavior to reach code marked with this function.

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