This works for most of its call sites. This is nice, because `emit` very
much makes sense as a consuming operation -- indeed,
`DiagnosticBuilderState` exists to ensure no diagnostic is emitted
twice, but it uses runtime checks.
For the small number of call sites where a consuming emit doesn't work,
the commit adds `DiagnosticBuilder::emit_without_consuming`. (This will
be removed in subsequent commits.)
Likewise, `emit_unless` becomes consuming. And `delay_as_bug` becomes
consuming, while `delay_as_bug_without_consuming` is added (which will
also be removed in subsequent commits.)
All this requires significant changes to `DiagnosticBuilder`'s chaining
methods. Currently `DiagnosticBuilder` method chaining uses a
non-consuming `&mut self -> &mut Self` style, which allows chaining to
be used when the chain ends in `emit()`, like so:
```
struct_err(msg).span(span).emit();
```
But it doesn't work when producing a `DiagnosticBuilder` value,
requiring this:
```
let mut err = self.struct_err(msg);
err.span(span);
err
```
This style of chaining won't work with consuming `emit` though. For
that, we need to use to a `self -> Self` style. That also would allow
`DiagnosticBuilder` production to be chained, e.g.:
```
self.struct_err(msg).span(span)
```
However, removing the `&mut self -> &mut Self` style would require that
individual modifications of a `DiagnosticBuilder` go from this:
```
err.span(span);
```
to this:
```
err = err.span(span);
```
There are *many* such places. I have a high tolerance for tedious
refactorings, but even I gave up after a long time trying to convert
them all.
Instead, this commit has it both ways: the existing `&mut self -> Self`
chaining methods are kept, and new `self -> Self` chaining methods are
added, all of which have a `_mv` suffix (short for "move"). Changes to
the existing `forward!` macro lets this happen with very little
additional boilerplate code. I chose to add the suffix to the new
chaining methods rather than the existing ones, because the number of
changes required is much smaller that way.
This doubled chainging is a bit clumsy, but I think it is worthwhile
because it allows a *lot* of good things to subsequently happen. In this
commit, there are many `mut` qualifiers removed in places where
diagnostics are emitted without being modified. In subsequent commits:
- chaining can be used more, making the code more concise;
- more use of chaining also permits the removal of redundant diagnostic
APIs like `struct_err_with_code`, which can be replaced easily with
`struct_err` + `code_mv`;
- `emit_without_diagnostic` can be removed, which simplifies a lot of
machinery, removing the need for `DiagnosticBuilderState`.
Remove `-Zreport-delayed-bugs`.
It's not used within the repository in any way (e.g. in tests), and doesn't seem useful.
It was added in #52568.
r? ````@oli-obk````
Because it's redundant w.r.t. `Diagnostic::is_lint`, which is present
for every diagnostic level.
`struct_lint_level_impl` was the only place that set the `Error` field
to `true`, and it's also the only place that calls
`Diagnostic::is_lint()` to set the `is_lint` field.
It's not used, and doesn't quite fit the general pattern.
Also, `Diagnostic::downgrade_to_delayed_bug` doesn't need to return
`&mut Self` for the same reason.
`Diagnostic` has 40 methods that return `&mut Self` and could be
considered setters. Four of them have a `set_` prefix. This doesn't seem
necessary for a type that implements the builder pattern. This commit
removes the `set_` prefixes on those four methods.
Lots of vectors of messages called `message` or `msg`. This commit
pluralizes them.
Note that `emit_message_default` and `emit_messages_default` both
already existed, and both process a vector, so I renamed the former
`emit_messages_default_inner` because it's called by the latter.
`DiagCtxt::span_bug` is different to the other `DiagCtxt::span_*`
methods. This commit makes it the same, which requires changing
`DiagCtxt::span_delayed_bug` to not do everything within the
`inner.borrow_mut()`.
- Take a `Vec` instead of an iterator, because that's all that is
needed.
- Do an early return for the "no bugs" case.
- Use `enumerate` and an `i == 0` test to identify the first bug.
Those changes mean the `no_bug` variable can be removed, which I found
hard to read.
`IntoDiagnostic` defaults to `ErrorGuaranteed`, because errors are the
most common diagnostic level. It makes sense to do likewise for the
closely-related (and much more widely used) `DiagnosticBuilder` type,
letting us write `DiagnosticBuilder<'a, ErrorGuaranteed>` as just
`DiagnosticBuilder<'a>`. This cuts over 200 lines of code due to many
multi-line things becoming single line things.
We can just get the error level in the `match` and then use
`DiagnosticBuilder::new`. This then means a number of `DiagCtxt`
functions are no longer needed, because this was the one place that used
them.
Note: the commit changes the treatment of spans for `Expect`, which was
different to all the other cases, but this has no apparent effect.
The easter egg ICE on `break rust` is weird: it's the one ICE in the
entire compiler that doesn't immediately abort, which makes it
annoyingly inconsistent.
This commit changes it to abort. As part of this, the extra notes are
now appended onto the bug dignostic, rather than being printed as
individual note diagnostics, which changes the output format a bit.
These changes don't interferes with the joke, but they do help with my
ongoing cleanups to error handling.
This lets different error levels share the same return type from
`emit_*`.
- A lot of inconsistencies in the `DiagCtxt` API are removed.
- `Noted` is removed.
- `FatalAbort` is introduced for fatal errors (abort via `raise`),
replacing the `EmissionGuarantee` impl for `!`.
- `Bug` is renamed `BugAbort` (to avoid clashing with `Level::Bug` and
to mirror `FatalAbort`), and modified to work in the new way with bug
errors (abort via panic).
- Various diagnostic creators and emitters updated to the new, better
signatures. Note that `DiagCtxt::bug` no longer needs to call
`panic_any`, because `emit` handles that.
Also shorten the obnoxiously long
`diagnostic_builder_emit_producing_guarantee` name.
And make all hand-written `IntoDiagnostic` impls generic, by using
`DiagnosticBuilder::new(dcx, level, ...)` instead of e.g.
`dcx.struct_err(...)`.
This means the `create_*` functions are the source of the error level.
This change will let us remove `struct_diagnostic`.
Note: `#[rustc_lint_diagnostics]` is added to `DiagnosticBuilder::new`,
it's necessary to pass diagnostics tests now that it's used in
`into_diagnostic` functions.
This commit replaces this pattern:
```
err.into_diagnostic(dcx)
```
with this pattern:
```
dcx.create_err(err)
```
in a lot of places.
It's a little shorter, makes the error level explicit, avoids some
`IntoDiagnostic` imports, and is a necessary prerequisite for the next
commit which will add a `level` arg to `into_diagnostic`.
This requires adding `track_caller` on `create_err` to avoid mucking up
the output of `tests/ui/track-diagnostics/track4.rs`. It probably should
have been there already.
Uplift `TypeAndMut` and `ClosureKind` to `rustc_type_ir`
Uplifts `TypeAndMut` and `ClosureKind`
I know I said I was just going to get rid of `TypeAndMut` (https://github.com/rust-lang/types-team/issues/124) but I think this is much simpler, lol
r? `@jackh726` or `@lcnr`
Currently, `emit_diagnostic` takes `&mut self`.
This commit changes it so `emit_diagnostic` takes `self` and the new
`emit_diagnostic_without_consuming` function takes `&mut self`.
I find the distinction useful. The former case is much more common, and
avoids a bunch of `mut` and `&mut` occurrences. We can also restrict the
latter with `pub(crate)` which is nice.
Compare `Handler::warn` and `Handler::span_warn`. Conceptually they are
almost identical. But their implementations are weirdly different.
`warn`:
- calls `DiagnosticBuilder::<()>::new(self, Warning(None), msg)`, then `emit()`
- which calls `G::diagnostic_builder_emit_producing_guarantee(self)`
- which calls `handler.emit_diagnostic(&mut db.inner.diagnostic)`
`span_warn`:
- calls `self.emit_diag_at_span(Diagnostic::new(Warning(None), msg), span)`
- which calls `self.emit_diagnostic(diag.set_span(sp))`
I.e. they both end up at `emit_diagnostic`, but take very different
routes to get there.
This commit changes `span_*` and similar ones to not use
`emit_diag_at_span`. Instead they just call `struct_span_*` + `emit`.
Some nice side-effects of this:
- `span_fatal` and `span_fatal_with_code` don't need
`FatalError.raise()`, because `emit` does that.
- `span_err` and `span_err_with_code` doesn't need `unwrap`.
- `struct_span_note`'s `span` arg type is changed from `Span` to
`impl Into<MultiSpan>` like all the other functions.
The `Handler` functions that directly emit diagnostics can be more
easily implemented using `struct_foo(msg).emit()`. This mirrors
`Handler::emit_err` which just does `create_err(err).emit()`.
`Handler::bug` is not converted because of weirdness involving
conflation bugs and fatal errors with `EmissionGuarantee`. I'll fix that
later.
It's necessary for `derive(Diagnostic)`, but is best avoided elsewhere
because there are clearer alternatives.
This required adding `Handler::struct_almost_fatal`.
detects redundant imports that can be eliminated.
for #117772 :
In order to facilitate review and modification, split the checking code and
removing redundant imports code into two PR.
according to a poll of gay people in my phone, purple is the most popular color to use for highlighting
| color | percentage |
| ---------- | ---------- |
| bold white | 6% |
| blue | 14% |
| cyan | 26% |
| purple | 37% |
| magenta | 17% |
unfortunately, purple is not supported by 16-color terminals, which rustc apparently wants to support for some reason.
until we require support for full 256-color terms (e.g. by doing the same feature detection as we currently do for urls), we can't use it.
instead, i have collapsed the purple votes into magenta on the theory that they're close, and also because magenta is pretty.
This is weird: `HandlerInner::emit` calls
`HandlerInner::emit_diagnostic`, but only after doing a
`treat-err-as-bug` check. Which is fine, *except* that there are
multiple others paths for an `Error` or `Fatal` diagnostic to be passed
to `HandlerInner::emit_diagnostic` without going through
`HandlerInner::emit`, e.g. `Handler::span_err` call
`Handler::emit_diag_at_span`, which calls `emit_diagnostic`.
So that suggests that the coverage for `treat-err-as-bug` is incomplete.
This commit removes `HandlerInner::emit` and moves the
`treat-err-as-bug` check to `HandlerInner::emit_diagnostic`, so it
cannot by bypassed.
`Handler` is a wrapper around `HanderInner`. Some functions on
on `Handler` just forward to the samed-named functions on
`HandlerInner`.
This commit removes as many of those as possible, implementing functions
on `Handler` where possible, to avoid the boilerplate required for
forwarding. The commit is moderately large but it's very mechanical.
Currently, `Handler::fatal` returns `FatalError`. But `Session::fatal`
returns `!`, because it calls `Handler::fatal` and then calls `raise` on
the result. This inconsistency is unfortunate.
This commit changes `Handler::fatal` to do the `raise` itself, changing
its return type to `!`. This is safe because there are only two calls to
`Handler::fatal`, one in `rustc_session` and one in
`rustc_codegen_cranelift`, and they both call `raise` on the result.
`HandlerInner::fatal` still returns `FatalError`, so I renamed it
`fatal_no_raise` to emphasise the return type difference.
Currently we always do this:
```
use rustc_fluent_macro::fluent_messages;
...
fluent_messages! { "./example.ftl" }
```
But there is no need, we can just do this everywhere:
```
rustc_fluent_macro::fluent_messages! { "./example.ftl" }
```
which is shorter.
Add `$message_type` field to distinguish json diagnostic outputs
Currently the json-formatted outputs have no way to unambiguously determine which kind of message is being output. A consumer can look for specific fields in the json object (eg "message"), but there's no guarantee that in future some other kind of output will have a field of the same name.
This PR adds a `"type"` field to add json outputs which can be used to unambiguously determine which kind of output it is. The mapping is:
`diagnostic`: regular compiler diagnostics
`artifact`: artifact notifications
`future_incompat`: Future incompatibility report
`unused_extern`: Unused crate warnings/errors
This matches the "internally tagged" representation for serde enums.
Don't emit delayed good-path bugs on panic
This should fix#117381, cc ``@RalfJung``
As opposed to delayed bugs, delayed *good path* bugs really don't make sense to show on panics.
- Sort dependencies and features sections.
- Add `tidy` markers to the sorted sections so they stay sorted.
- Remove empty `[lib`] sections.
- Remove "See more keys..." comments.
Excluded files:
- rustc_codegen_{cranelift,gcc}, because they're external.
- rustc_lexer, because it has external use.
- stable_mir, because it has external use.
Format all the let-chains in compiler crates
Since rust-lang/rustfmt#5910 has landed, soon we will have support for formatting let-chains (as soon as rustfmt syncs and beta gets bumped).
This PR applies the changes [from master rustfmt to rust-lang/rust eagerly](https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/out.20formatting.20of.20prs/near/374997516), so that the next beta bump does not have to deal with a 200+ file diff and can remain concerned with other things like `cfg(bootstrap)` -- #113637 was a pain to land, for example, because of let-else.
I will also add this commit to the ignore list after it has landed.
The commands that were run -- I'm not great at bash-foo, but this applies rustfmt to every compiler crate, and then reverts the two crates that should probably be formatted out-of-tree.
```
~/rustfmt $ ls -1d ~/rust/compiler/* | xargs -I@ cargo run --bin rustfmt -- `@/src/lib.rs` --config-path ~/rust --edition=2021 # format all of the compiler crates
~/rust $ git checkout HEAD -- compiler/rustc_codegen_{gcc,cranelift} # revert changes to cg-gcc and cg-clif
```
cc `@rust-lang/rustfmt`
r? `@WaffleLapkin` or `@Nilstrieb` who said they may be able to review this purely mechanical PR :>
cc `@Mark-Simulacrum` and `@petrochenkov,` who had some thoughts on the order of operations with big formatting changes in https://github.com/rust-lang/rust/pull/95262#issue-1178993801. I think the situation has changed since then, given that let-chains support exists on master rustfmt now, and I'm fairly confident that this formatting PR should land even if *bootstrap* rustfmt doesn't yet format let-chains in order to lessen the burden of the next beta bump.
Allow `-Z treat-err-as-bug=0`
Makes `-Z treat-err-as-bug=0` behave as if the option wasn't present instead of asking the value to be ⩾ 1. This enables a quick on/off of the option, as you only need to change one character instead of removing the whole `-Z`.
Also update some text, e.g.
```bash
$ rustc -Z help | grep treat-err-as-bug
-Z treat-err-as-bug=val -- treat error number `val` that occurs as bug
```
where the value could be interpreted as an error code instead of an ordinal.
Currently the json-formatted outputs have no way to unambiguously
determine which kind of message is being output. A consumer can look for
specific fields in the json object (eg "message"), but there's no
guarantee that in future some other kind of output will have a field of
the same name.
This PR adds a `"type"` field to add json outputs which can be used to
unambiguously determine which kind of output it is. The mapping is:
diagnostic: regular compiler diagnostics
artifact: artifact notifications
future_incompat: Report of future incompatibility
unused_extern: Unused crate warnings/errors
This matches the "internally tagged" representation for serde enums.
Use `Freeze` for `SourceFile`
This uses the `Freeze` type in `SourceFile` to let accessing `external_src` and `lines` be lock-free.
Behavior of `add_external_src` is changed to set `ExternalSourceKind::AbsentErr` on a hash mismatch which matches the documentation. `ExternalSourceKind::Unneeded` was removed as it's unused.
Based on https://github.com/rust-lang/rust/pull/115401.
After https://github.com/rust-lang/rust/pull/114104, `rust-gpu` is unable to create a custom `Emitter` as the bounds have changed to include `WriteColor`.
I was able to work around this by adding `termcolor` as a direct dependency, but I believe this should be exposed as part of `rustc_errors` proper.
See https://github.com/rust-lang/rust/pull/102992 for why `rust-gpu` needs to create a custom emitter.
Lots of tiny incremental simplifications of `EmitterWriter` internals
ignore the first commit, it's https://github.com/rust-lang/rust/pull/114088 squashed and rebased, but it's needed to use to use `derive_setters`, as they need a newer `syn` version.
Then this PR starts out with removing many arguments that are almost always defaulted to `None` or `false` and replace them with builder methods that can set these fields in the few cases that want to set them.
After that it's one commit after the other that removes or merges things until everything becomes some very simple trait objects
It lints against features that are inteded to be internal to the
compiler and standard library. Implements MCP #596.
We allow `internal_features` in the standard library and compiler as those
use many features and this _is_ the standard library from the "internal to the compiler and
standard library" after all.
Marking some features as internal wasn't exactly the most scientific approach, I just marked some
mostly obvious features. While there is a categorization in the macro,
it's not very well upheld (should probably be fixed in another PR).
We always pass `-Ainternal_features` in the testsuite
About 400 UI tests and several other tests use internal features.
Instead of throwing the attribute on each one, just always allow them.
There's nothing wrong with testing internal features^^
fix(resolve): update the ambiguity glob binding as warning recursively
Fixes#47525Fixes#56593, but `issue-56593-2.rs` is not fixed to ensure backward compatibility.
Fixes#98467Fixes#105235Fixes#112713
This PR had added a field called `warn_ambiguous` in `NameBinding` which is only for back compatibly reason and used for lint.
More details: https://github.com/rust-lang/rust/pull/112743
r? `@petrochenkov`
Implement diagnostic translation for rustc-errors
This is my first PR to rustc yeah~
I'm going to implement diagnostic translation on rustc-errors crate.
This PR is WIP, the reason of opening this as draft, I want to show my code to prevent the issue caused by misunderstanding and also I have few questions.
Some error messages are processed by `pluralize!` macro which determines to use plural word or not. From now, I make two kinds of keys and combine with enum but I'm not sure is this best method to do it.
Is there any prefered method to do this? => This resolved on conversation on PR.
I'll remain to perform force-push until my first implementation looks good to me
Currently, Clippy, Miri, Rustfmt, and rustc all use an environment variable to
indicate that output should be blessed, but they use different variable names.
In order to improve consistency, this patch applies the following changes:
- Emit `RUSTC_BLESS` within `prepare_cargo_test` so it is always
available
- Change usage of `MIRI_BLESS` in the Miri subtree to use `RUSTC_BLESS`
- Change usage of `BLESS` in the Clippy subtree to `RUSTC_BLESS`
- Change usage of `BLESS` in the Rustfmt subtree to `RUSTC_BLESS`
- Adjust the blessable test in `rustc_errors` to use this same
convention
- Update documentation where applicable
Any tools that uses `RUSTC_BLESS` should check that it is set to any value
other than `"0"`.
Split some functions with many arguments into builder pattern functions
r? `@estebank`
This doesn't resolve all of the ones in rustc, mostly because I need to do other cleanups in order to be able to use some builder derives from crates.io
Works around https://github.com/rust-lang/rust/issues/90672 by making `x test rustfmt --bless` format itself instead of testing that it is formatted
If a raw string was used in the `env!` invocation, then it should also
be shown in the diagnostic messages as a raw string.
Signed-off-by: David Wood <david@davidtw.co>
Per #112156, using `&` in `format!` may cause a small perf delay, so I tried to clean up one module at a time format usage. This PR includes a few removals of the ref in format (they do compile locally without the ref), as well as a few format inlining for consistency.
Use the correct span for displaying the line following a derive sugge…
`span` here is the main span of the diagnostic. In the linked issue's case, this belongs to `main.rs`. However, the line numbers (and line we are trying to display) are in `name.rs`, so using `span_to_lines` gives us the wrong `FileLines`.
Use `parts[0].span` (the span of the suggestion) here like the rest of the code does to get the right file.
Not sure if this needs a dedicated test because this fixes an existing error in the UI suite
Fixes#113844
Implement rust-lang/compiler-team#578.
When an ICE is encountered on nightly releases, the new rustc panic
handler will also write the contents of the backtrace to disk. If any
`delay_span_bug`s are encountered, their backtrace is also added to the
file. The platform and rustc version will also be collected.
Currently, the output of `rustc --explain foo` displays the raw markdown in a
pager. This is acceptable, but using actual formatting makes it easier to
understand.
This patch consists of three major components:
1. A markdown parser. This is an extremely simple non-backtracking recursive
implementation that requires normalization of the final token stream
2. A utility to write the token stream to an output buffer
3. Configuration within rustc_driver_impl to invoke this combination for
`--explain`. Like the current implementation, it first attempts to print to
a pager with a fallback colorized terminal, and standard print as a last
resort.
If color is disabled, or if the output does not support it, or if printing
with color fails, it will write the raw markdown (which matches current
behavior).
Pagers known to support color are: `less` (with `-r`), `bat` (aka `catbat`),
and `delta`.
The markdown parser does not support the entire markdown specification, but
should support the following with reasonable accuracy:
- Headings, including formatting
- Comments
- Code, inline and fenced block (no indented block)
- Strong, emphasis, and strikethrough formatted text
- Links, anchor, inline, and reference-style
- Horizontal rules
- Unordered and ordered list items, including formatting
This parser and writer should be reusable by other systems if ever needed.
Sometimes, especially with MIR validation, the backtraces from delayed
bugs are noise and make it harder to look at them. Respect the
environment variable and don't print it when the user doesn't want it.
Each of `{D,Subd}iagnosticMessage::{Str,Eager}` has a comment:
```
// FIXME(davidtwco): can a `Cow<'static, str>` be used here?
```
This commit answers that question in the affirmative. It's not the most
compelling change ever, but it might be worth merging.
This requires changing the `impl<'a> From<&'a str>` impls to `impl
From<&'static str>`, which involves a bunch of knock-on changes that
require/result in call sites being a little more precise about exactly
what kind of string they use to create errors, and not just `&str`. This
will result in fewer unnecessary allocations, though this will not have
any notable perf effects given that these are error paths.
Note that I was lazy within Clippy, using `to_string` in a few places to
preserve the existing string imprecision. I could have used `impl
Into<{D,Subd}iagnosticMessage>` in various places as is done in the
compiler, but that would have required changes to *many* call sites
(mostly changing `&format("...")` to `format!("...")`) which didn't seem
worthwhile.
Ensure Fluent messages are in alphabetical order
Fixes#111847
This adds a tidy check to ensure Fluent messages are in alphabetical order, as well as sorting all existing messages. I think the error could be worded better, would appreciate suggestions.
<details>
<summary>Script used to sort files</summary>
```py
import sys
import re
fn = sys.argv[1]
with open(fn, 'r') as f:
data = f.read().split("\n")
chunks = []
cur = ""
for line in data:
if re.match(r"^([a-zA-Z0-9_]+)\s*=\s*", line):
chunks.append(cur)
cur = ""
cur += line + "\n"
chunks.append(cur)
chunks.sort()
with open(fn, 'w') as f:
f.write(''.join(chunks).strip("\n\n") + "\n")
```
</details>
Fix overflow in error emitter
Fix#109854Close#94171 (was already fixed before but missing test)
This bug happens when a multipart suggestion spans more than one line.
The fix is to update the `acc` variable, which didn't handle the case when the text to remove spans multiple lines but the text to add spans only one line.
Also, use `usize::try_from` instead of `as usize` to detect overflows earlier in the future, and point to the source of the overflow (the original issue points to a different place where this value is used, not where the overflow had happened).
And finally add an `if start != end` check to avoid doing any extra work in case of empty ranges.
Long explanation:
Given this test case:
```rust
fn generate_setter() {
String::with_capacity(
//~^ ERROR this function takes 1 argument but 3 arguments were supplied
generate_setter,
r#"
pub(crate) struct Person<T: Clone> {}
"#,
r#""#,
);
}
```
The compiler will try to convert that code into the following:
```rust
fn generate_setter() {
String::with_capacity(
//~^ ERROR this function takes 1 argument but 3 arguments were supplied
/* usize */,
);
}
```
So it creates a suggestion with 3 separate parts:
```
// Replace "generate_setter" with "/* usize */"
SubstitutionPart { span: fuzz_input.rs:4:5: 4:20 (#0), snippet: "/* usize */" }
// Remove second arg (multiline string)
SubstitutionPart { span: fuzz_input.rs:4:20: 7:3 (#0), snippet: "" }
// Remove third arg (r#""#)
SubstitutionPart { span: fuzz_input.rs:7:3: 8:11 (#0), snippet: "" }
```
Each of this parts gets a separate `SubstitutionHighlight` (this marks the relevant text green in a terminal, the values are 0-indexed so `start: 4` means column 5):
```
SubstitutionHighlight { start: 4, end: 15 }
SubstitutionHighlight { start: 15, end: 15 }
SubstitutionHighlight { start: 18446744073709551614, end: 18446744073709551614 }
```
The 2nd and 3rd suggestion are empty (start = end) because they only remove text, so there are no additions to highlight. But the 3rd span has overflowed because the compiler assumes that the 3rd suggestion is on the same line as the first suggestion. The 2nd span starts at column 20 and the highlight starts at column 16 (15+1), so that suggestion is good. But since the 3rd span starts at column 3, the result is `3 - 4`, or column -1, which turns into -2 with 0-indexed, and that's equivalent to `18446744073709551614 as isize`.
With this fix, the resulting `SubstitutionHighlight` are:
```
SubstitutionHighlight { start: 4, end: 15 }
SubstitutionHighlight { start: 15, end: 15 }
SubstitutionHighlight { start: 15, end: 15 }
```
As expected. I guess ideally we shouldn't emit empty highlights when removing text, but I am too scared to change that.
Before:
```
= note: delayed at 0: <rustc_errors::HandlerInner>::emit_diagnostic
at ./compiler/rustc_errors/src/lib.rs:1335:29
1: <rustc_errors::Handler>::emit_diagnostic
at ./compiler/rustc_errors/src/lib.rs:1124:9
...
```
After:
```
= note: delayed at compiler/rustc_parse/src/parser/diagnostics.rs:2158:28
0: <rustc_errors::HandlerInner>::emit_diagnostic
at ./compiler/rustc_errors/src/lib.rs:1335:29
1: <rustc_errors::Handler>::emit_diagnostic
at ./compiler/rustc_errors/src/lib.rs:1124:9
```
This both makes the relevant frame easier to find without having to dig
through diagnostic internals, and avoids the weird-looking formatting
for the first frame.
Introduce `DynSend` and `DynSync` auto trait for parallel compiler
part of parallel-rustc #101566
This PR introduces `DynSend / DynSync` trait and `FromDyn / IntoDyn` structure in rustc_data_structure::marker. `FromDyn` can dynamically check data structures for thread safety when switching to parallel environments (such as calling `par_for_each_in`). This happens only when `-Z threads > 1` so it doesn't affect single-threaded mode's compile efficiency.
r? `@cjgillot`
Currently a `{D,Subd}iagnosticMessage` can be created from any type that
impls `Into<String>`. That includes `&str`, `String`, and `Cow<'static,
str>`, which are reasonable. It also includes `&String`, which is pretty
weird, and results in many places making unnecessary allocations for
patterns like this:
```
self.fatal(&format!(...))
```
This creates a string with `format!`, takes a reference, passes the
reference to `fatal`, which does an `into()`, which clones the
reference, doing a second allocation. Two allocations for a single
string, bleh.
This commit changes the `From` impls so that you can only create a
`{D,Subd}iagnosticMessage` from `&str`, `String`, or `Cow<'static,
str>`. This requires changing all the places that currently create one
from a `&String`. Most of these are of the `&format!(...)` form
described above; each one removes an unnecessary static `&`, plus an
allocation when executed. There are also a few places where the existing
use of `&String` was more reasonable; these now just use `clone()` at
the call site.
As well as making the code nicer and more efficient, this is a step
towards possibly using `Cow<'static, str>` in
`{D,Subd}iagnosticMessage::{Str,Eager}`. That would require changing
the `From<&'a str>` impls to `From<&'static str>`, which is doable, but
I'm not yet sure if it's worthwhile.
Add `rustc_fluent_macro` to decouple fluent from `rustc_macros`
Fluent, with all the icu4x it brings in, takes quite some time to compile. `fluent_messages!` is only needed in further downstream rustc crates, but is blocking more upstream crates like `rustc_index`. By splitting it out, we allow `rustc_macros` to be compiled earlier, which speeds up `x check compiler` by about 5 seconds (and even more after the needless dependency on `serde_json` is removed from `rustc_data_structures`).
Encode hashes as bytes, not varint
In a few places, we store hashes as `u64` or `u128` and then apply `derive(Decodable, Encodable)` to the enclosing struct/enum. It is more efficient to encode hashes directly than try to apply some varint encoding. This PR adds two new types `Hash64` and `Hash128` which are produced by `StableHasher` and replace every use of storing a `u64` or `u128` that represents a hash.
Distribution of the byte lengths of leb128 encodings, from `x build --stage 2` with `incremental = true`
Before:
```
( 1) 373418203 (53.7%, 53.7%): 1
( 2) 196240113 (28.2%, 81.9%): 3
( 3) 108157958 (15.6%, 97.5%): 2
( 4) 17213120 ( 2.5%, 99.9%): 4
( 5) 223614 ( 0.0%,100.0%): 9
( 6) 216262 ( 0.0%,100.0%): 10
( 7) 15447 ( 0.0%,100.0%): 5
( 8) 3633 ( 0.0%,100.0%): 19
( 9) 3030 ( 0.0%,100.0%): 8
( 10) 1167 ( 0.0%,100.0%): 18
( 11) 1032 ( 0.0%,100.0%): 7
( 12) 1003 ( 0.0%,100.0%): 6
( 13) 10 ( 0.0%,100.0%): 16
( 14) 10 ( 0.0%,100.0%): 17
( 15) 5 ( 0.0%,100.0%): 12
( 16) 4 ( 0.0%,100.0%): 14
```
After:
```
( 1) 372939136 (53.7%, 53.7%): 1
( 2) 196240140 (28.3%, 82.0%): 3
( 3) 108014969 (15.6%, 97.5%): 2
( 4) 17192375 ( 2.5%,100.0%): 4
( 5) 435 ( 0.0%,100.0%): 5
( 6) 83 ( 0.0%,100.0%): 18
( 7) 79 ( 0.0%,100.0%): 10
( 8) 50 ( 0.0%,100.0%): 9
( 9) 6 ( 0.0%,100.0%): 19
```
The remaining 9 or 10 and 18 or 19 are `u64` and `u128` respectively that have the high bits set. As far as I can tell these are coming primarily from `SwitchTargets`.
Fluent, with all the icu4x it brings in, takes quite some time to
compile. `fluent_messages!` is only needed in further downstream rustc
crates, but is blocking more upstream crates like `rustc_index`. By
splitting it out, we allow `rustc_macros` to be compiled earlier, which
speeds up `x check compiler` by about 5 seconds (and even more after the
needless dependency on `serde_json` is removed from
`rustc_data_structures`).
Migrate most of `rustc_builtin_macros` to diagnostic impls
cc #100717
This is a couple of days work, but I decided to stop for now before the PR becomes too big. There's around 50 unresolved failures when `rustc::untranslatable_diagnostic` is denied, which I'll finish addressing once this PR goes thtough
A couple of outputs have changed, but in all instances I think the changes are an improvement/are more consistent with other diagnostics (although I'm happy to revert any which seem worse)
This makes it easier to open the messages file while developing on features.
The commit was the result of automatted changes:
for p in compiler/rustc_*; do mv $p/locales/en-US.ftl $p/messages.ftl; rmdir $p/locales; done
for p in compiler/rustc_*; do sed -i "s#\.\./locales/en-US.ftl#../messages.ftl#" $p/src/lib.rs; done
statically guarantee that current error codes are documented
Closes#61137 (that's right!)
Pretty simple refactor (often just a change from `Result<Option<&str>>` to `Result<&str>`)
r? `@GuillaumeGomez` (could you specially look at 53044158eff0d64673a6100f701c57b484232aca? I believe you wrote that in the first place, just want to make sure you're happy with the change)
Add `ErrorGuaranteed` to `hir::{Expr,Ty}Kind::Err` variants
First step in making the `Err` variants of `ExprKind` and `TyKind` require an `ErrorGuaranteed` during parsing. Making the corresponding AST versions require `ErrorGuaranteed` is a bit harder, whereas it was pretty easy to do this for HIR, so let's do that first.
The only weird thing about this PR is that `ErrorGuaranteed` is moved to `rustc_span`. This is *certainly* not the right place to put it, but `rustc_hir` cannot depend on `rustc_error` because the latter already depends on the former. Should I just pull out some of the error machinery from `rustc_error` into an even more minimal crate that `rustc_hir` can depend on? Advice would be appreciated.
Extend `CodegenBackend` trait with a function returning the translation
resources from the codegen backend, which can be added to the complete
list of resources provided to the emitter.
Signed-off-by: David Wood <david.wood@huawei.com>
`run-make/translation` had some targets that weren't listed in `all` and
thus weren't being tested - the behaviour that should have been being
tested was basically correct fortunately.
Signed-off-by: David Wood <david.wood@huawei.com>
Instead of loading the Fluent resources for every crate in
`rustc_error_messages`, each crate generates typed identifiers for its
own diagnostics and creates a static which are pulled together in the
`rustc_driver` crate and provided to the diagnostic emitter.
Signed-off-by: David Wood <david.wood@huawei.com>
Don't recover lifetimes/labels containing emojis as character literals
Fixes#108019.
Note that at the time of this commit, `unic-emoji-char` seems to have data tables only up to Unicode 5.0, but Unicode is already newer than this.
A newer emoji such as `🥺` will not be recognized as an emoji but older emojis such as `🐱` will.
This PR leaves a couple of FIXMEs where `unic_emoji_char::is_emoji` is used.
Note that at the time of this commit, `unic-emoji-char` seems to have
data tables only up to Unicode 5.0, but Unicode is already newer than
this.
A newer emoji such as `🥺` will not be recognized as an emoji
but older emojis such as `🐱` will.
Introduce `-Zterminal-urls` to use OSC8 for error codes
Terminals supporting the OSC8 Hyperlink Extension can support inline anchors where the text is user defineable but clicking on it opens a browser to a specified URLs, just like `<a href="URL">` does in HTML.
https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda
Terminals supporting the OSC8 Hyperlink Extension can support inline
anchors where the text is user defineable but clicking on it opens a
browser to a specified URLs, just like `<a href="URL">` does in HTML.
https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda
Implement `IntoDiagnosticArg` for `&'a T` when `T` implements
`IntoDiagnosticArg` and `Clone`. Makes it easier to write diagnostic
structs that borrow something which implements `IntoDiagnosticArg`.
Signed-off-by: David Wood <david.wood@huawei.com>
Support for emission of notes was added in f8ebc72 but `emit_note` and
`create_note` functions weren't added to `Handler`.
Signed-off-by: David Wood <david.wood@huawei.com>
Collect and emit proper backtraces for `delay_span_bug`s
This is a follow-up to #106317, which addresses this comment (https://github.com/rust-lang/rust/issues/106267#issuecomment-1367507507) which notes that `delay_span_bug`s' backtraces are nonsense.
Captures and emits the backtrace of the delayed span bug when it's *created*, rather than using the backtrace of the place where delayed bugs are flushed.
---
To test, I delayed a span bug during HIR typeck, specifically in `typeck_with_fallback`...
Before, note `flush_delayed` on frame 18. This is at the end of the compilation session, far from where the bug is being delayed.
```
error: internal compiler error: test
--> /home/ubuntu/test.rs:1:1
|
1 | fn main() {}
| ^^^^^^^^^
|
= note: delayed at compiler/rustc_hir_typeck/src/lib.rs:196:14
thread 'rustc' panicked at 'Box<dyn Any>', compiler/rustc_errors/src/lib.rs:1634:13
stack backtrace:
0: 0x7f9c3ec69dd1 - std::backtrace_rs::backtrace::libunwind::trace::h26056f81198c6594
at /home/ubuntu/rust2/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
1: 0x7f9c3ec69dd1 - std::backtrace_rs::backtrace::trace_unsynchronized::hacfb345a0c6d5bb1
at /home/ubuntu/rust2/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
2: 0x7f9c3ec69dd1 - std::sys_common::backtrace::_print_fmt::h18ea6016ac8030f3
at /home/ubuntu/rust2/library/std/src/sys_common/backtrace.rs:65:5
3: 0x7f9c3ec69dd1 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::he35dde201d0c2d09
at /home/ubuntu/rust2/library/std/src/sys_common/backtrace.rs:44:22
4: 0x7f9c3ecee308 - core::fmt::write::h094ad263467a053c
at /home/ubuntu/rust2/library/core/src/fmt/mod.rs:1208:17
5: 0x7f9c3ec8aaf1 - std::io::Write::write_fmt::hd47b4e2324b4d9b7
at /home/ubuntu/rust2/library/std/src/io/mod.rs:1682:15
6: 0x7f9c3ec69bfa - std::sys_common::backtrace::_print::h43044162653a17fc
at /home/ubuntu/rust2/library/std/src/sys_common/backtrace.rs:47:5
7: 0x7f9c3ec69bfa - std::sys_common::backtrace::print::hc8605da258fa5aeb
at /home/ubuntu/rust2/library/std/src/sys_common/backtrace.rs:34:9
8: 0x7f9c3ec4db87 - std::panicking::default_hook::{{closure}}::h9e37f23f75122a15
9: 0x7f9c3ec4d97b - std::panicking::default_hook::h602873a063f84da2
at /home/ubuntu/rust2/library/std/src/panicking.rs:286:9
10: 0x7f9c3f6672b2 - <alloc[48d7b30605060536]::boxed::Box<dyn for<'a, 'b> core[672e3947e150d6c6]::ops::function::Fn<(&'a core[672e3947e150d6c6]::panic::panic_info::PanicInfo<'b>,), Output = ()> + core[672e3947e150d6c6]::marker::Send + core[672e3947e150d6c6]::marker::Sync> as core[672e3947e150d6c6]::ops::function::Fn<(&core[672e3947e150d6c6]::panic::panic_info::PanicInfo,)>>::call
at /home/ubuntu/rust2/library/alloc/src/boxed.rs:2002:9
11: 0x7f9c3f6672b2 - rustc_driver[f5b6d32d8905ecdd]::DEFAULT_HOOK::{closure#0}::{closure#0}
at /home/ubuntu/rust2/compiler/rustc_driver/src/lib.rs:1204:17
12: 0x7f9c3ec4e0d3 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::hfd13333ca953ae8e
at /home/ubuntu/rust2/library/alloc/src/boxed.rs:2002:9
13: 0x7f9c3ec4e0d3 - std::panicking::rust_panic_with_hook::h45753e10264ebe7e
at /home/ubuntu/rust2/library/std/src/panicking.rs:692:13
14: 0x7f9c422a1aa3 - std[3330b4673efabfce]::panicking::begin_panic::<rustc_errors[1b15f4e7e49d1fd5]::ExplicitBug>::{closure#0}
at /home/ubuntu/rust2/library/std/src/panicking.rs:608:9
15: 0x7f9c422a1a46 - std[3330b4673efabfce]::sys_common::backtrace::__rust_end_short_backtrace::<std[3330b4673efabfce]::panicking::begin_panic<rustc_errors[1b15f4e7e49d1fd5]::ExplicitBug>::{closure#0}, !>
at /home/ubuntu/rust2/library/std/src/sys_common/backtrace.rs:137:18
16: 0x7f9c3f63a996 - std[3330b4673efabfce]::panicking::begin_panic::<rustc_errors[1b15f4e7e49d1fd5]::ExplicitBug>
at /home/ubuntu/rust2/library/std/src/panicking.rs:607:12
17: 0x7f9c4227a496 - std[3330b4673efabfce]::panic::panic_any::<rustc_errors[1b15f4e7e49d1fd5]::ExplicitBug>
at /home/ubuntu/rust2/library/std/src/panic.rs:61:5
18: 0x7f9c4227cdf7 - <rustc_errors[1b15f4e7e49d1fd5]::HandlerInner>::flush_delayed::<alloc[48d7b30605060536]::vec::Vec<rustc_errors[1b15f4e7e49d1fd5]::diagnostic::Diagnostic>, &str, rustc_errors[1b15f4e7e49d1fd5]::ExplicitBug>
at /home/ubuntu/rust2/compiler/rustc_errors/src/lib.rs:1634:13
19: 0x7f9c422498cf - <rustc_errors[1b15f4e7e49d1fd5]::Handler>::flush_delayed
at /home/ubuntu/rust2/compiler/rustc_errors/src/lib.rs:1225:9
[ FRAMES INTENTIONALLY OMITTED ]
44: 0x7f9c3f6f3584 - <std[3330b4673efabfce]:🧵:Builder>::spawn_unchecked_::<rustc_interface[947706ead88047d0]::util::run_in_thread_pool_with_globals<rustc_interface[947706ead88047d0]::interface::run_compiler<core[672e3947e150d6c6]::result::Result<(), rustc_errors[1b15f4e7e49d1fd5]::ErrorGuaranteed>, rustc_driver[f5b6d32d8905ecdd]::run_compiler::{closure#1}>::{closure#0}, core[672e3947e150d6c6]::result::Result<(), rustc_errors[1b15f4e7e49d1fd5]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[672e3947e150d6c6]::result::Result<(), rustc_errors[1b15f4e7e49d1fd5]::ErrorGuaranteed>>::{closure#1}
at /home/ubuntu/rust2/library/std/src/thread/mod.rs:549:30
45: 0x7f9c3f6f3584 - <<std[3330b4673efabfce]:🧵:Builder>::spawn_unchecked_<rustc_interface[947706ead88047d0]::util::run_in_thread_pool_with_globals<rustc_interface[947706ead88047d0]::interface::run_compiler<core[672e3947e150d6c6]::result::Result<(), rustc_errors[1b15f4e7e49d1fd5]::ErrorGuaranteed>, rustc_driver[f5b6d32d8905ecdd]::run_compiler::{closure#1}>::{closure#0}, core[672e3947e150d6c6]::result::Result<(), rustc_errors[1b15f4e7e49d1fd5]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[672e3947e150d6c6]::result::Result<(), rustc_errors[1b15f4e7e49d1fd5]::ErrorGuaranteed>>::{closure#1} as core[672e3947e150d6c6]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
at /home/ubuntu/rust2/library/core/src/ops/function.rs:250:5
46: 0x7f9c3ec81968 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::he8b26fc22c6f51ec
at /home/ubuntu/rust2/library/alloc/src/boxed.rs:1988:9
47: 0x7f9c3ec81968 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h5cf9cbe75a8c3ddc
at /home/ubuntu/rust2/library/alloc/src/boxed.rs:1988:9
48: 0x7f9c3ec5f99c - std::sys::unix:🧵:Thread:🆕:thread_start::h2d6dd4455e97d031
at /home/ubuntu/rust2/library/std/src/sys/unix/thread.rs:108:17
49: 0x7f9c37c69609 - start_thread
50: 0x7f9c3ead0133 - clone
51: 0x0 - <unknown>
```
After, note `typeck_with_fallback` on the 5th frame, that's where we *actually* need to be pointed to:
```
error: internal compiler error: no errors encountered even though `delay_span_bug` issued
error: internal compiler error: test
--> /home/ubuntu/test.rs:1:1
|
1 | fn main() {}
| ^^^^^^^^^
|
= note: delayed at 0: <rustc_errors::HandlerInner>::emit_diagnostic
at ./compiler/rustc_errors/src/lib.rs:1279:29
1: <rustc_errors::HandlerInner>::delay_span_bug::<rustc_span::span_encoding::Span, &str>
at ./compiler/rustc_errors/src/lib.rs:1553:9
2: <rustc_errors::Handler>::delay_span_bug::<rustc_span::span_encoding::Span, &str>
at ./compiler/rustc_errors/src/lib.rs:995:9
3: <rustc_session::session::Session>::delay_span_bug::<rustc_span::span_encoding::Span, &str>
at ./compiler/rustc_session/src/session.rs:600:9
4: rustc_hir_typeck::typeck_with_fallback::<rustc_hir_typeck::typeck::{closure#0}>::{closure#0}
at ./compiler/rustc_hir_typeck/src/lib.rs:196:5
5: rustc_hir_typeck::typeck_with_fallback::<rustc_hir_typeck::typeck::{closure#0}>
at ./compiler/rustc_hir_typeck/src/lib.rs:185:36
6: rustc_hir_typeck::typeck
at ./compiler/rustc_hir_typeck/src/lib.rs:166:9
[ FRAMES INTENTIONALLY OMITTED ]
108: std::panicking::try::<core::result::Result<(), rustc_errors::ErrorGuaranteed>, core::panic::unwind_safe::AssertUnwindSafe<<std:🧵:Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_driver::run_compiler::{closure#1}>::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#1}::{closure#0}>>
at ./library/std/src/panicking.rs:447:19
109: std::panic::catch_unwind::<core::panic::unwind_safe::AssertUnwindSafe<<std:🧵:Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_driver::run_compiler::{closure#1}>::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#1}::{closure#0}>, core::result::Result<(), rustc_errors::ErrorGuaranteed>>
at ./library/std/src/panic.rs:140:14
110: <std:🧵:Builder>::spawn_unchecked_::<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_driver::run_compiler::{closure#1}>::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#1}
at ./library/std/src/thread/mod.rs:549:30
111: <<std:🧵:Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_driver::run_compiler::{closure#1}>::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
at ./library/core/src/ops/function.rs:250:5
112: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
at ./library/alloc/src/boxed.rs:1988:9
113: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
at ./library/alloc/src/boxed.rs:1988:9
114: std::sys::unix:🧵:Thread:🆕:thread_start
at ./library/std/src/sys/unix/thread.rs:108:17
115: start_thread
116: clone
```
Migrate `codegen_ssa` to diagnostics structs - [Part 3]
Completes migrating `codegen_ssa` module except 2 outstanding errors that depend on other crates:
1. [`rustc_middle::mir::interpret::InterpError`](b6097f2e1b/compiler/rustc_middle/src/mir/interpret/error.rs (L475)): I saw `rustc_middle` is unassigned, I am open to take this work.
2. `codegen_llvm`'s use of `fn span_invalid_monomorphization_error`, which I started to replace in the [last commit](9a31b3cdda) of this PR, but would like to know the team's preference on how we should keep replacing the other macros:
2.1. Update macros to expect a `Diagnostic`
2.2. Remove macros and expand the code on each use.
See [some examples of the different options in this experimental commit](64aee83e80)
_Part 2 - https://github.com/rust-lang/rust/pull/103792_
r? ``@davidtwco``
Cc ``@compiler-errors``
Encode spans relative to the enclosing item -- enable on nightly
Follow-up to #84373 with the flag `-Zincremental-relative-spans` set by default.
This PR seeks to remove one of the main shortcomings of incremental: the handling of spans.
Changing the contents of a function may require redoing part of the compilation process for another function in another file because of span information is changed.
Within one file: all the spans in HIR change, so typechecking had to be re-done.
Between files: spans of associated types/consts/functions change, so type-based resolution needs to be re-done (hygiene information is stored in the span).
The flag `-Zincremental-relative-spans` encodes local spans relative to the span of an item, stored inside the `source_span` query.
Trap: stashed diagnostics are referenced by the "raw" span, so stealing them requires to remove the span's parent.
In order to avoid too much traffic in the span interner, span encoding uses the `ctxt_or_tag` field to encode:
- the parent when the `SyntaxContext` is 0;
- the `SyntaxContext` when the parent is `None`.
Even with this, the PR creates a lot of traffic to the Span interner, when a Span has both a LocalDefId parent and a non-root SyntaxContext. They appear in lowering, when we add a parent to all spans, including those which come from macros, and during inlining when we mark inlined spans.
The last commit changes how queries of `LocalDefId` manage their cache. I can put this in a separate PR if required.
Possible future directions:
- validate that all spans are marked in HIR validation;
- mark macro-expanded spans relative to the def-site and not the use-site.
compiler: remove unnecessary imports and qualified paths
Some of these imports were necessary before Edition 2021, others were already in the prelude.
I hope it's fine that this PR is so spread-out across files :/
This migrates everything but the `mbe` and `proc_macro` modules. It also
contains a few cleanups and drive-by/accidental diagnostic improvements
which can be seen in the diff for the UI tests.
