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# Error code E0622

#### Note: this error code is no longer emitted by the compiler.

An intrinsic was declared without being a function.

Erroneous code example:

    #![feature(intrinsics)]
    #![allow(internal_features)]

    extern "C" {
        #[rustc_intrinsic]
        pub static atomic_singlethreadfence_seqcst: unsafe fn();
        // error: intrinsic must be a function
    }

    fn main() { unsafe { atomic_singlethreadfence_seqcst(); } }

An intrinsic is a function available for use in a given programming language whose implementation is handled specially by the compiler. In order to fix this error, just declare a function. Example:

    #![feature(intrinsics)]
    #![allow(internal_features)]

    #[rustc_intrinsic]
    pub unsafe fn atomic_singlethreadfence_seqcst(); // ok!

    fn main() { unsafe { atomic_singlethreadfence_seqcst(); } }