https://github.com/rust-lang/rust http://git.dreamy.place/mirrors/rust/atom?h=beta 2025-08-14T15:43:39+00:00 2025-08-14T15:43:39+00:00 lcnr rust@lcnr.de 2025-08-13T12:08:53+00:00 urn:sha1:3ebf611005370734ddf7ce22e41ac502e4fff59a 2025-08-13T12:03:26+00:00 lcnr rust@lcnr.de 2025-08-07T09:30:24+00:00 urn:sha1:a95a2ac476ef04ccf8cfabd35e6fcdb9569f053d 2025-06-09T14:08:12+00:00 Jack Wrenn jack@wrenn.fyi 2025-06-04T15:58:01+00:00 urn:sha1:e9eae28eee0a99c64e81f4fdf87d3c76241e56bd Previously, `rustc_transmute`'s layout representations were genericized over `R`, a reference. Now, it's instead genericized over representations of type and region. This allows us to move reference transmutability logic from `rustc_trait_selection` to `rustc_transmutability` (and thus unit test it independently of the compiler), and — in a follow-up PR — will make it possible to support analyzing function pointer transmutability with minimal surgery. 2024-12-12T23:36:27+00:00 Esteban Küber esteban@kuber.com.ar 2024-12-11T21:48:33+00:00 urn:sha1:49a22a4245bd6dfd3646a6658e0f90a2ab0657ad 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 2024-08-18T18:31:06+00:00 Jack Wrenn jack@wrenn.fyi 2024-08-14T20:10:28+00:00 urn:sha1:17995d5cc2e75b65b8bd6b77ad30b0c764500c0c Modifies `BikeshedIntrinsicFrom` to forbid lifetime extensions on references. This static check can be opted out of with the `Assume::lifetimes` flag. Fixes #129097 2024-06-13T00:57:23+00:00 Michael Goulet michael@errs.io 2024-06-08T18:02:01+00:00 urn:sha1:c453c82de4868aee46563ec908dab218153d46eb 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.). 2024-03-15T17:55:49+00:00 Jack Wrenn jack@wrenn.fyi 2024-03-15T17:55:49+00:00 urn:sha1:107807d3932c2765580725604802f76935239723 2024-03-13T15:53:48+00:00 Jack Wrenn jack@wrenn.fyi 2024-03-13T00:11:36+00:00 urn:sha1:216df4a8e6358a515ba95fb1a92864d1b94c37f3 The source referent absolutely must be smaller than the destination referent of a ref-to-ref transmute; the excess bytes referenced cannot arise from thin air, even if those bytes are uninitialized.