rust/library/core
Matthias Krüger c4d0c08925
Rollup merge of #126956 - joboet:fmt_no_extern_ty, r=RalfJung
core: avoid `extern type`s in formatting infrastructure

```@RalfJung``` [said](https://rust-lang.zulipchat.com/#narrow/stream/219381-t-libs/topic/Use.20of.20.60extern.20type.60.20in.20formatting.20machinery/near/446552837):

>How attached are y'all to using `extern type` in the formatting machinery?
Seems like this was introduced a [long time ago](34ef8f5441). However, it's also [not really compatible with Stacked Borrows](https://github.com/rust-lang/unsafe-code-guidelines/issues/256), and only works currently because we effectively treat references-to-extern-type almost like raw pointers in Stacked Borrows -- which of course is unsound, it's not how LLVM works. I was planning to make Miri emit a warning when this happens to avoid cases like [this](https://github.com/rust-lang/rust/issues/126814#issuecomment-2183816373) where people use extern type specifically to silence Miri without realizing what happens. but with the formatting machinery using  extern type, this warning would just show up everywhere...
>
> The "proper" way to do this in Stacked Borrows is to use raw pointers (or `NonNull`).

This PR does just that.

r? ```@RalfJung```
2024-06-28 08:34:08 +02:00
..
benches Write char::DebugEscape sequences using write_str 2024-05-20 10:04:44 +02:00
src Rollup merge of #126956 - joboet:fmt_no_extern_ty, r=RalfJung 2024-06-28 08:34:08 +02:00
tests regression test for leaks in the the Filter::next_chunk implementation 2024-06-25 23:22:27 +02:00
Cargo.toml Remove now outdated comment since we bumped stage0 2024-05-24 08:08:41 +02:00