1ad218f3af
As our implementation of MCP411 nears completion and we begin to solicit testing, it's no longer reasonable to expect testers to type or remember `BikeshedIntrinsicFrom`. The name degrades the ease-of-reading of documentation, and the overall experience of using compiler safe transmute. Tentatively, we'll instead adopt `TransmuteFrom`. This name seems to be the one most likely to be stabilized, after discussion on Zulip [1]. We may want to revisit the ordering of `Src` and `Dst` before stabilization, at which point we'd likely consider `TransmuteInto` or `Transmute`. [1] https://rust-lang.zulipchat.com/#narrow/stream/216762-project-safe-transmute/topic/What.20should.20.60BikeshedIntrinsicFrom.60.20be.20named.3F
35 lines
708 B
Rust
35 lines
708 B
Rust
//@ check-pass
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//! This UI test was introduced as check-fail by a buggy bug-fix for an ICE. In
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//! fact, this transmutation should be valid.
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#![crate_type = "lib"]
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#![feature(transmutability)]
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#![allow(dead_code)]
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use std::mem::size_of;
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mod assert {
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use std::mem::{Assume, TransmuteFrom};
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pub fn is_maybe_transmutable<Src, Dst>()
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where
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Dst: TransmuteFrom<
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Src,
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{ Assume { alignment: true, lifetimes: true, safety: true, validity: true } },
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>,
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{
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}
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}
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fn test() {
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#[repr(C, align(2))]
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struct A(u8, u8);
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#[repr(C)]
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struct B(u8, u8);
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assert_eq!(size_of::<A>(), size_of::<B>());
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assert::is_maybe_transmutable::<B, A>();
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}
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