30 lines
707 B
Rust
30 lines
707 B
Rust
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#![feature(ptr_offset_from)]
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fn test_raw() { unsafe {
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let buf = [0u32; 4];
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let x = buf.as_ptr() as *const u8;
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let y = x.offset(12);
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assert_eq!(y.offset_from(x), 12);
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assert_eq!(x.offset_from(y), -12);
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assert_eq!((y as *const u32).offset_from(x as *const u32), 12/4);
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assert_eq!((x as *const u32).offset_from(y as *const u32), -12/4);
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let x = (((x as usize) * 2) / 2) as *const u8;
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assert_eq!(y.offset_from(x), 12);
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assert_eq!(x.offset_from(y), -12);
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} }
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// This also internally uses offset_from.
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fn test_vec_into_iter() {
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let v = Vec::<i32>::new();
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let i = v.into_iter();
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i.size_hint();
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}
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fn main() {
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test_raw();
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test_vec_into_iter();
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}
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