This is done by adding a new `IsJoint` field to `TokenStream::Tree`,
which simplifies a lot of `match` statements. And likewise for
`CursorKind`.

The commit also adds a new method `TokenTree:stream()` which can replace
a choice between `.into()` and `.joint()`.

We need to reduce the alignment with the used offset. If the offset
isn't known, we need to reduce with the element size to support
arbitrary offsets.

Weirdly, we were deciding between a help note and a structured
suggestion based on whether the import candidate span was a dummy—but
we weren't using that span in any case! The dummy-ness of the span
(which appears to be a matter of this-crate vs. other-crate
definition) isn't the right criterion by which we should decide
whether it's germane to mention that "there is an enum variant";
instead, let's use the someness of `def` (which is used as the
`has_unexpected_resolution` argument to `error_code`).

Since `import_candidate_to_paths` has no other callers, we are free to
stop returning the span and rename the function. By using
`span_suggestions_`, we leverage the max-suggestions output limit
already built in to the emitter, thus resolving rust-lang#56028.

In the matter of message wording, "you can" is redundant (and perhaps
too informal); prefer the imperative.

The present author regrets not thinking of a more eloquent way to do
this.

…dtwco

enum type instead of variant suggestion unification

Fixes rust-lang#56028.

Weirdly, we were deciding between a help note and a structured suggestion based on whether the import candidate span was a dummy—but we weren't using that span in any case! The dummy-ness of the span (which appears to be a matter of this-crate vs. other-crate definition) isn't the right criterion by which we should decide whether it's germane to mention that "there is an enum variant"; instead, let's use the someness of `def` (which is used as the `has_unexpected_resolution` argument to `error_code`).

Since `import_candidate_to_paths` has no other callers, we are free to stop returning the span and rename the function. By using `span_suggestions_`, we leverage the max-suggestions output limit already built in to the emitter, thus resolving rust-lang#56028.

In the matter of message wording, "you can" is redundant (and perhaps too informal); prefer the imperative.

In a second commit, we do some unprincipled special-casing to correct and beautify suggestions for `Option` and `Result` (where the existing code was being confused by their being reexported in the prelude).

r? @davidtwco

… r=davidtwco

Fix mutable references in `static mut`

fixes rust-lang#56903

Simplify MIR generation for logical operations

Reduces one block and one branch from MIR generated for a logical operator.

Mark tuple structs as live if their constructors are used

fixes rust-lang#56281

…petrochenkov

Remove `TokenStream::JointTree`.

This is done by adding a new `IsJoint` field to `TokenStream::Tree`,
which simplifies a lot of `match` statements. And likewise for
`CursorKind`.

The commit also adds a new method `TokenTree:stream()` which can replace
a choice between `.into()` and `.joint()`.

…zackmdavis

Correct strings for raw pointer deref and array access suggestions

Fixes rust-lang#56714.
Fixes rust-lang#56963.

r? @zackmdavis

Point to cause of `fn` expected return type

Fix rust-lang#48136.

…r=Centril

fix deprecation warnings in liballoc benches

Fix alignment for array indexing

We need to reduce the alignment with the used offset. If the offset isn't known, use the element size, as this will yield the minimum possible alignment.

This handles both direct array indexing, and array repeat expressions.

Fixes rust-lang#56927.

r? @nagisa

…fn, r=oli-obk

Stabilize min_const_unsafe_fn in 1.33

Fixes rust-lang#55607

r? @oli-obk