Co-authored-by: lcnr <rust@lcnr.de>

…ering assertion

Issue: <rust-lang#128717>

Parser has error recovery for Unicode-confusables, which includes the
right parentheses `)`. If a multi-byte right parentheses look-alike
reaches the argument removal suggestion diagnostics, it would trigger an
assertion because the diagnostics used `- BytePos(1)` which can land
within a multi-byte codepoint.

This is fixed by using `SourceMap::end_point` to find the final right
delimiter codepoint, which correctly respects codepoint boundaries.

For codepoint boundary assertion triggered by a let stmt compound
assignment removal suggestion when encountering recovered multi-byte
compound ops.

Issue: <rust-lang#128845>

…t codepoint boundaries

Previously we would try to issue a suggestion for `let x <op>= 1`, i.e.
a compound assignment within a `let` binding, to remove the `<op>`. The
suggestion code unfortunately incorrectly assumed that the `<op>` is an
exactly-1-byte ASCII character, but this assumption is incorrect because
we also recover Unicode-confusables like `➖=` as `-=`. In this example,
the suggestion code used a `+ BytePos(1)` to calculate the span of the
`<op>` codepoint that looks like `-` but the mult-byte Unicode
look-alike would cause the suggested removal span to be inside a
multi-byte codepoint boundary, triggering a codepoint boundary
assertion.

Issue: <rust-lang#128845>

…ld=always (even if that breaks backtraces)

…bose mode

…=saethlin

miri: make vtable addresses not globally unique

Miri currently gives vtables a unique global address. That's not actually matching reality though. So this PR enables Miri to generate different addresses for the same type-trait pair.

To avoid generating an unbounded number of `AllocId` (and consuming unbounded amounts of memory), we use the "salt" technique that we also already use for giving constants non-unique addresses: the cache is keyed on a "salt" value n top of the actually relevant key, and Miri picks a random salt (currently in the range `0..16`) each time it needs to choose an `AllocId` for one of these globals -- that means we'll get up to 16 different addresses for each vtable. The salt scheme is integrated into the global allocation deduplication logic in `tcx`, and also used for functions and string literals. (So this also fixes the problem that casting the same function to a fn ptr over and over will consume unbounded memory.)

r? `@saethlin`
Fixes rust-lang/miri#3737

Add `Steal::is_stolen()`

Writers of rustc drivers (such as myself) often encounter stealing issues. It is currently impossible to gracefully handle them. This PR adds a `Steal::is_stolen()` function for that purpose.

Fix the name of signal 19 in library/std/src/sys/pal/unix/process/process_unix/tests.rs for mips/sparc linux

relate to rust-lang#128816

Use `SourceMap::end_point` instead of `- BytePos(1)` in arg removal suggestion

Previously, we tried to remove extra arg commas when providing extra arg removal suggestions. One of
the edge cases is having to account for an arg that has a closing delimiter `)` following it.
However, the previous suggestion code assumed that the delimiter is in fact exactly the 1-byte `)`
character. This assumption was proven incorrect, because we recover from Unicode-confusable
delimiters in the parser, which means that the ending delimiter could be a multi-byte codepoint
that looks *like* a `)`. Subtracing 1 byte could land us in the middle of a codepoint, triggering a
codepoint boundary assertion.

This is fixed by using `SourceMap::end_point` which properly accounts for codepoint boundaries.

Fixes rust-lang#128717.

cc `@fmease` and rust-lang#128790

Ensure let stmt compound assignment removal suggestion respect codepoint boundaries

Previously we would try to issue a suggestion for `let x <op>= 1`, i.e.
a compound assignment within a `let` binding, to remove the `<op>`. The
suggestion code unfortunately incorrectly assumed that the `<op>` is an
exactly-1-byte ASCII character, but this assumption is incorrect because
we also recover Unicode-confusables like `➖=` as `-=`. In this example,
the suggestion code used a `+ BytePos(1)` to calculate the span of the
`<op>` codepoint that looks like `-` but the mult-byte Unicode
look-alike would cause the suggested removal span to be inside a
multi-byte codepoint boundary, triggering a codepoint boundary
assertion.

The fix is to use `SourceMap::start_point(token_span)` which properly accounts for codepoint boundaries.

Fixes rust-lang#128845.

cc rust-lang#128790

r? `@fmease`

…-ozkan

Disable verbose bootstrap command failure logging by default

One of my recent bootstrap command refactoring PRs enabled verbose logging of command failures by default. While this is great for debugging bootstrap, in many situations it's just too verbose and prevents the user from seeing the actual printed stdout/stderr, which usually contains much more useful information.

This PR reverts that logic, and only prints a detailed error when `-v` is passed to bootstrap.

r? `@onur-ozkan`