| // Copyright 2014 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. |
| |
| // #11303, #11040: |
| // This would previously crash on i686 Linux due to abi differences |
| // between returning an Option<T> and T, where T is a non nullable |
| // pointer. |
| // If we have an enum with two variants such that one is zero sized |
| // and the other contains a nonnullable pointer, we don't use a |
| // separate discriminant. Instead we use that pointer field to differentiate |
| // between the 2 cases. |
| // Also, if the variant with the nonnullable pointer has no other fields |
| // then we simply express the enum as just a pointer and not wrap it |
| // in a struct. |
| |
| |
| use std::mem; |
| |
| #[inline(never)] |
| extern "C" fn foo(x: &isize) -> Option<&isize> { Some(x) } |
| |
| static FOO: isize = 0xDEADBEE; |
| |
| pub fn main() { |
| unsafe { |
| let f: extern "C" fn(&isize) -> &isize = |
| mem::transmute(foo as extern "C" fn(&isize) -> Option<&isize>); |
| assert_eq!(*f(&FOO), FOO); |
| } |
| } |
