https://github.com/rust-lang/rust http://git.dreamy.place/mirrors/rust/atom?h=master 2024-08-27T14:05:54+00:00 2024-08-27T14:05:54+00:00 Jack Wrenn jack@wrenn.fyi 2024-08-27T14:05:54+00:00 urn:sha1:1ad218f3af806c1f0c14e8b44656318b913a3906 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 2024-04-08T15:36:52+00:00 Jack Wrenn jack@wrenn.fyi 2024-03-19T14:49:13+00:00 urn:sha1:3aa14e3b2e61739e8d0ec7883f9c185821ca5da2 In its first step of computing transmutability, `rustc_transmutability` constructs a byte-level representation of type layout (`Tree`). Previously, this representation was computed for ADTs by inspecting the ADT definition and performing our own layout computations. This process was error-prone, verbose, and limited our ability to analyze many types (particularly default-repr types). In this PR, we instead construct `Tree`s from `rustc_target::abi::Layout`s. This helps ensure that layout optimizations are reflected our analyses, and increases the kinds of types we can now analyze, including: - default repr ADTs - transparent unions - `UnsafeCell`-containing types Overall, this PR expands the expressvity of `rustc_transmutability` to be much closer to the transmutability analysis performed by miri. Future PRs will work to close the remaining gaps (e.g., support for `Box`, raw pointers, `NonZero*`, coroutines, etc.).