You declared a pattern as an argument in a foreign function declaration.
Erroneous code example:
extern { fn foo((a, b): (u32, u32)); // error: patterns aren't allowed in foreign // function declarations }
Please replace the pattern argument with a regular one. Example:
struct SomeStruct { a: u32, b: u32, } extern { fn foo(s: SomeStruct); // ok! }
Or:
extern { fn foo(a: (u32, u32)); // ok! }