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

    pub unsafe extern "rust-intrinsic" fn unreachable() -> !

🔬 This is a nightly-only experimental API. (`core_intrinsics`)

intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library

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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