9fed13030c
Extend ptr::null and null_mut to all thin (including extern) types Fixes https://github.com/rust-lang/rust/issues/93959 This change was accepted in https://rust-lang.github.io/rfcs/2580-ptr-meta.html Note that this changes the signature of **stable** functions. The change should be backward-compatible, but it is **insta-stable** since it cannot (easily, at all?) be made available only through a `#![feature(…)]` opt-in. The RFC also proposed the same change for `NonNull::dangling`, which makes sense it terms of its signature but not in terms of its implementation. `dangling` uses `align_of()` as an address. But what `align_of()` should be for extern types or whether it should be allowed at all remains an open question. This commit depends on https://github.com/rust-lang/rust/pull/93977, which is not yet part of the bootstrap compiler. So `#[cfg]` is used to only apply the change in stage 1+. As far a I know bounds cannot be made conditional with `#[cfg]`, so the entire functions are duplicated. This is unfortunate but temporary. Since this duplication makes it less obvious in the diff, the new definitions differ in: * More permissive bounds (`Thin` instead of implied `Sized`) * Different implementation * Having `rustc_allow_const_fn_unstable(const_fn_trait_bound)` * Having `rustc_allow_const_fn_unstable(ptr_metadata)` |
||
|---|---|---|
| .. | ||
| alloc | ||
| backtrace@b02ed04a7e | ||
| core | ||
| panic_abort | ||
| panic_unwind | ||
| portable-simd | ||
| proc_macro | ||
| profiler_builtins | ||
| rtstartup | ||
| rustc-std-workspace-alloc | ||
| rustc-std-workspace-core | ||
| rustc-std-workspace-std | ||
| std | ||
| stdarch@28335054b1 | ||
| test | ||
| unwind | ||