Error code E0130

A pattern was declared as an argument in a foreign function declaration.

Erroneous code example:

#![allow(unused)] fn main() { extern "C" { fn foo((a, b): (u32, u32)); // error: patterns aren't allowed in foreign // function declarations } }

To fix this error, replace the pattern argument with a regular one. Example:

#![allow(unused)] fn main() { struct SomeStruct { a: u32, b: u32, } extern "C" { fn foo(s: SomeStruct); // ok! } }

Or:

#![allow(unused)] fn main() { extern "C" { fn foo(a: (u32, u32)); // ok! } }