Use line numbers relative to the function in mir-opt tests
As shown in #99770, the line numbers can be a big source of needless and confusing diffs. This PR adds a new flag `-Zmir-pretty-relative-line-numbers` to make them relative to the function declaration, which avoids most needless diffs from attribute changes.
`@JakobDegen` told me that there has been a zulip conversation about disabling line numbers with mixed opinions, so I'd like to get some feedback here, for this hopefully better solution.
r? rust-lang/wg-mir-opt
fix: Do completions in path qualifier position
Fixes https://github.com/rust-lang/rust-analyzer/issues/12566
Not too happy with the duplication needed for this, but it is what it is. Completions in path qualifiers will have to be filtered properly still, but its better to show too many completions for this than too few for now.
Sync `rust-analyzer`, add `rust-analyzer-proc-macro-srv` binary to Rustc component
As discussed earlier with `@jyn514` and `@pietroalbini,` I'm also going to use this PR to have `dist::Rustc` build the `rust-analyzer-proc-macro-srv` binary introduced in:
* https://github.com/rust-lang/rust-analyzer/pull/12871
This avoids monomorphizing all linker code for each codegen backend and
will allow passing in extra information to the archive builder from the
codegen backend.
mem::uninitialized: mitigate many incorrect uses of this function
Alternative to https://github.com/rust-lang/rust/pull/98966: fill memory with `0x01` rather than leaving it uninit. This is definitely bitewise valid for all `bool` and nonnull types, and also those `Option<&T>` that we started putting `noundef` on. However it is still invalid for `char` and some enums, and on references the `dereferenceable` attribute is still violated, so the generated LLVM IR still has UB -- but in fewer cases, and `dereferenceable` is hopefully less likely to cause problems than clearly incorrect range annotations.
This can make using `mem::uninitialized` a lot slower, but that function has been deprecated for years and we keep telling everyone to move to `MaybeUninit` because it is basically impossible to use `mem::uninitialized` correctly. For the cases where that hasn't helped (and all the old code out there that nobody will ever update), we can at least mitigate the effect of using this API. Note that this is *not* in any way a stable guarantee -- it is still UB to call `mem::uninitialized::<bool>()`, and Miri will call it out as such.
This is somewhat similar to https://github.com/rust-lang/rust/pull/87032, which proposed to make `uninitialized` return a buffer filled with 0x00. However
- That PR also proposed to reduce the situations in which we panic, which I don't think we should do at this time.
- The 0x01 bit pattern means that nonnull requirements are satisfied, which (due to references) is the most common validity invariant.
`@5225225` I hope I am using `cfg(sanitize)` the right way; I was not sure for which ones to test here.
Cc https://github.com/rust-lang/rust/issues/66151
Fixes https://github.com/rust-lang/rust/issues/87675
