rust/tests/ui/transmutability/structs
Jack Wrenn 3aa14e3b2e Compute transmutability from rustc_target::abi::Layout
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.).
2024-04-08 15:36:52 +00:00
..
repr Compute transmutability from rustc_target::abi::Layout 2024-04-08 15:36:52 +00:00
should_order_fields_correctly.rs safe transmute: revise safety analysis 2024-02-27 16:22:32 +00:00