src/test/compile-fail/E0617.rs

// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// ignore-tidy-linelength

extern {
    fn printf(c: *const i8, ...);
}

fn main() {
    unsafe {
        printf(::std::ptr::null(), 0f32);
        //~^ ERROR can't pass `f32` to variadic function, cast to `c_double` [E0617]
        printf(::std::ptr::null(), 0i8);
        //~^ ERROR can't pass `i8` to variadic function, cast to `c_int` [E0617]
        printf(::std::ptr::null(), 0i16);
        //~^ ERROR can't pass `i16` to variadic function, cast to `c_int` [E0617]
        printf(::std::ptr::null(), 0u8);
        //~^ ERROR can't pass `u8` to variadic function, cast to `c_uint` [E0617]
        printf(::std::ptr::null(), 0u16);
        //~^ ERROR can't pass `u16` to variadic function, cast to `c_uint` [E0617]
        printf(::std::ptr::null(), printf);
        //~^ ERROR can't pass `unsafe extern "C" fn(*const i8, ...) {printf}` to variadic function, cast to `unsafe extern "C" fn(*const i8, ...)` [E0617]
    }
}