If we have a call such as `foo(&mut buf)` and after reference
collapsing the type is inferred as `&T` where-as the required type is
`&mut T`, don't suggest `foo(&mut mut buf)`. This is wrong syntactically
and the issue lies elsewhere, not in the borrow.

Fixes rust-lang#105645

A number of tests under ui/const-ptr and ui/consts are currently
failing on big-endian platforms as the binary encoding of some
constants is hard-coded in the stderr test files.  Fix this by
providing a normalize-stderr-test rule that strips out the
raw bytes hex dump, so the comparison can be done in an
endianness-independent manner.  Note that in most cases, this
means the tests are now also independent of word size, so the
32bit and 64bit cases can be re-unified.

To keep tests that verify the details of those raw bytes dumps,
a new test case raw-bytes.rs performs the tests where the hex
dumps were stripped out a second time, but only on little-
endian platforms.

In addition, src/test/ui/const-ptr/forbidden_slices.rs exposes
an endian-specific difference in this diagnostic output:
   constructing invalid value at .<deref>[0]: encountered 0x11,
   but expected a boolean
depending on which byte of D0 is not a boolean value (0 or 1).
Fixed this by choosing a value of D0 that differs from 0 or 1
in all bytes.

Fixes part of rust-lang#105383.

see rust-lang#106182

…errors_for_expr_obligation

Fuchsia already uses SCS by default for C/C++ code on ARM hardware.
This patch allows SCS to be used for Rust code as well.

Instead of just switching to a probe, check for different matches, and see how many there are.
If one, unify it, otherwise return true and let it be unified later.

This prevents an ICE due to a value not actually being evaluatable later.

Simplify match statement

Add multiple tests
- 1 test for checking `N + 1 + 1` does not unify with `N+1`
- 2 tests for checking that a function that uses two parameters only returns the parameter that
  is actually used.
- Check exact repeat predicates

…yUwU

Change a commit_if_ok call to probe

Removes an over-eager `commit_if_ok` which makes inference worse.

I'm not entirely sure whether it's ok to remove the check that types are the same, because casting seems to cause equality checks with incorrect types?

Fixes rust-lang#105037

r? ```@BoxyUwU```

Remove invalid case for mutable borrow suggestion

If we have a call such as `foo(&mut buf)` and after reference
collapsing the type is inferred as `&T` where-as the required type is
`&mut T`, don't suggest `foo(&mut mut buf)`. This is wrong syntactically
and the issue lies elsewhere, not in the borrow.

Fixes rust-lang#105645

…r=oli-obk

Fix ui constant tests for big-endian platforms

A number of tests under ui/const-ptr and ui/consts are currently failing on big-endian platforms as the binary encoding of some constants is hard-coded in the stderr test files.

Fix this by a combination of two types of changes:

- Where possible (i.e. where the particular value of a constant does not affect the purpose of the test), choose constant values that have the same encoding on big- and little-endian platforms.

- Where this is not possible, provide a normalize-stderr-test rule that transforms the printed big-endian encoding of such constants into the corresponding little-endian form.

Fixes part of rust-lang#105383.

Enable Shadow Call Stack for Fuchsia on AArch64

Fuchsia already uses SCS by default for C/C++ code on ARM hardware. This patch allows SCS to be used for Rust code as well.

…, r=oli-obk

Move `check_region_obligations_and_report_errors` to `TypeErrCtxt`

Makes sense for this function to live with its sibling `resolve_regions_and_report_errors`, around which it's basically just a wrapper.

Fix incorrect suggestion for extra `&` in pattern

Closes rust-lang#106182

…r=lcnr

Simplify some canonical type alias names

* delete the `Canonicalized<'tcx>` type alias in favor for `Canonical<'tcx>`
* `CanonicalizedQueryResponse` -> `CanonicalQueryResponse`

I don't particularly care about the latter, but it should be consistent. We could alternatively delete the first alias and rename the struct to `Canonicalized`, and then keep the name of `CanonicalizedQueryResponse` untouched.

…=lcnr

Use FxIndexSet when updating obligation causes in `adjust_fulfillment_errors_for_expr_obligation`

I have no idea how to test this reliably, but I've **manually** verified it fixes the instability in rust-lang#106417 that isn't due to dtolnay/trybuild#212.

Fixes rust-lang#106417

…ters-borrowck, r=estebank

Use fmt named parameters in rustc_borrowck

…aumeGomez

error-code docs improvements (No. 2)

- Added empty error-code docs for `E0208`, `E0640` and `E0717` with the "internal" header as discussed on Discord.
- Wrote docs and UI test for `E0711`, again with the header.
- `tidy` changes are common-sense and make everything pass, `style.rs` hack is annoying though.

r? ```@GuillaumeGomez```