rust/compiler/rustc_mir_build
Matthias Krüger 93bf791e8b
Rollup merge of #129248 - compiler-errors:raw-ref-deref, r=nnethercote
Taking a raw ref (`&raw (const|mut)`) of a deref of pointer (`*ptr`) is always safe

T-opsem decided in https://github.com/rust-lang/reference/pull/1387 that `*ptr` is only unsafe if the place is accessed. This means that taking a raw ref of a deref expr is always safe, since it doesn't constitute a read.

This also relaxes the `DEREF_NULLPTR` lint to stop warning in the case of raw ref of a deref'd nullptr, and updates its docs to reflect that change in the UB specification.

This does not change the behavior of `addr_of!((*ptr).field)`, since field projections still require the projection is in-bounds.

I'm on the fence whether this requires an FCP, since it's something that is guaranteed by the reference you could ostensibly call this a bugfix since we were counting truly safe operations as unsafe. Perhaps someone on opsem has a strong opinion? cc `@rust-lang/opsem`
2024-10-24 10:35:39 +02:00
..
src Rollup merge of #129248 - compiler-errors:raw-ref-deref, r=nnethercote 2024-10-24 10:35:39 +02:00
Cargo.toml
messages.ftl Change error message 2024-10-08 00:23:28 +02:00