When a snapshot test fails, it only emits a `.pending-snap` file for the first
snapshot assertion that actually failed, because subsequent assertions aren't
executed. That makes it cumbersome to re-bless tests that contain multiple
snapshot assertions.
Make frame spans appear on a separate trace line
This PR changes tracing_chrome's `tracing::Layer` so that if a span has the "tracing_separate_line" field as one of the span arguments, that span is put on a separate trace line. See https://github.com/rust-lang/miri/pull/4451 for an earlier attempt and for screenshots explaining better what I mean by "separate trace line".
This PR also makes the "frame" span use this feature (so it appears on a separate trace line, see https://github.com/rust-lang/miri/pull/4451 for motivation), but passes `tracing::field::Empty` as the span parameter value so it is ignored by other tracing layers (e.g. the logger):
```rust
info_span!("frame", tracing_separate_line = Empty, "{}", instance);
```
<details><summary>Also see the following discussion I had with ``@RalfJung</summary>``
> Is there no way to attach metadata we could use instead?
[These](https://docs.rs/tracing-core/0.1.34/src/tracing_core/metadata.rs.html#57) are the **static** metadata items we can control about a span. We can't add more metadata outside of them. The most relevant are:
- `name` (for the frame span it's currently "frame")
- `target` which acts as the category (for the frame span it's currently "rustc_const_eval::interpret::stack" by default)
- `fields` which contains a list of the *names* of each of the arguments passed to the `span!` macro (for the frame span it's currently ["message"], where "message" is the default identifier for data passed in the `format!` syntax)
When the tracing code is called at runtime, the **dynamic** values of the arguments are collected into a [`ValueSet`](https://docs.rs/tracing-core/0.1.34/src/tracing_core/field.rs.html#166). Each argument value stored there corresponds with one of the static names stored in `fields` (see above).
---
We have already determined that filtering out spans by `name` is not a good idea, and I would say the same goes for `target`. Both the `name` and the `target` fields are printed to stderr when `MIRI_LOG=` is enabled, so changing them to contain an identifier (e.g. "frame:tracing_separate_root" instead of "frame" as the name) would uselessly clutter the text logs (unless we add one more filter [there](https://github.com/rust-lang/rust/blob/master/compiler/rustc_log/src/lib.rs#L137), but then it gets even more complicated).
```rust
// examples of how the above (problematic) solutions would look like
info_span!("frame:tracing_separate_root", "{}", instance);
info_span!(target: "tracing_separate_root", "frame", "{}", instance);
```
---
So that leaves us with `fields` and their runtime values. Now, my initial thought (inspired by [this comment](https://github.com/rust-lang/miri/pull/4451#issuecomment-3068072303)) was to use a field with the static name "tracing_separate_root" and with a dynamic boolean value of "true". In `tracing_chrome.rs` we can easily check if this field is true and act accordingly. This would work but then again this field would also be picked up by the logger when `MIRI_LOG=` is enabled, and would uselessly clutter the text logs.
```rust
// example of how the above (problematic) solution would look like
info_span!("frame", tracing_separate_root = true, "{}", instance);
```
---
To avoid cluttering the text logs, we can instead set "tracing_separate_root" to the dynamic value of `tracing::field::Empty`. Citing from [here](https://docs.rs/tracing/0.1.41/tracing/field/struct.Empty.html), "when a field’s value is `Empty`, it will not be recorded". "not being recorded" means that the field and its value won't be printed to stderr text logs, nor will it be printed by any other tracing layers that might be attached in the future. In `tracing_chrome.rs` we would still be able to check if "tracing_separate_root" is in the list of static `fields`, and act accordingly. So I believe this solution would effectively allow us to attach metadata to a span in a way that does not clutter logs and still allows being read in `tracing_chrome.rs`.
If we ever wanted to pass arbitrary metadata (i.e. not just a present/not present flag), it would be possible with a custom `Empty` that also holds data and implement `Value` without doing anything ([like `Empty` does](https://docs.rs/tracing-core/0.1.34/src/tracing_core/field.rs.html#775)).
```rust
// example of how the above solution would look like
info_span!("frame", tracing_separate_root = tracing::field::Empty, "{}", instance);
```
</details>
Reword mismatched-lifetime-syntaxes text based on feedback
Key changes include:
- Removal of the word "syntax" from the lint message. More accurately, it could have been something like "syntax group" or "syntax category", but avoiding it completely is easier.
- The primary lint message now reflects exactly which mismatch is occurring, instead of trying to be general. A new `help` line is general across the mismatch kinds.
- Suggestions have been reduced to be more minimal, no longer also changing non-idiomatic but unrelated aspects.
- Suggestion text no longer mentions changes when those changes don't occur in that specific suggestion.
r? ``@jieyouxu``
update to literal-escaper-0.0.5
Quoting from the changelog, this version brings:
- Use `NonZero<char/u8>` in `unescape_c_str` and `check_raw_c_str` to statically exclude nuls
- Add `#[inline]` to small functions for improved performance
Fix handling of SCRIPT_ARG in docker images
Instead of making this a build parameter, pass the SCRIPT as an environment variable.
To this purpose, normalize on always referring to a script in `/scripts`.
For i686-gnu-nopt-2 I had to create a separate script, because Docker seems to be really terrible at command line argument parsing, so it's not possible to pass an environment variable that contains whitespace.
Fixes https://github.com/rust-lang/rust/issues/143962.
try-job: `dist-x86_64-linux`
try-job: `i686-gnu-nopt-*`
try-job: `i686-gnu-*`
try-job: `x86_64-gnu-llvm-19-*`
try-job: `x86_64-gnu-llvm-20-*`
ci cleanup: rustdoc-gui-test now installs browser-ui-test
this removes the need for --unsafe-perm in the Dockerfile.
cc ```@GuillaumeGomez``` ```@Kobzol```
Implement unstable trait impl
This PR allows marking impls of stable trait with stable type as unstable.
## Approach
In std/core, an impl can be marked as unstable by annotating it with ``#[unstable_feature_bound(feat_name)]``. This will add a ``ClauseKind::Unstable_Feature(feat_name)`` to the list of predicates in ``predicates_of`` .
When an unstable impl's function is called, we will first iterate through all the goals in ``param_env`` to check if there is any ``ClauseKind::UnstableFeature(feat_name)`` in ``param_env``.
The existence of ``ClauseKind::Unstable_Feature(feat_name)`` in ``param_env`` means an``#[unstable_feature_bound(feat_name)]`` is present at the call site of the function, so we allow the check to succeed in this case.
If ``ClauseKind::UnstableFeature(feat_name)`` does not exist in ``param_env``, we will still allow the check to succeed for either of the cases below:
1. The feature is enabled through ``#[feature(feat_name)]`` outside of std / core.
2. We are in codegen because we may be monomorphizing a body from an upstream crate which had an unstable feature enabled that the downstream crate do not.
For the rest of the case, it will fail with ambiguity.
## Limitation
In this PR, we do not support:
1. using items that need ``#[unstable_feature_bound]`` within stable APIs
2. annotate main function with ``#[unstable_feature_bound]``
3. annotate ``#[unstable_feature_bound]`` on items other than free function and impl
## Acknowledgement
The design and mentoring are done by `@BoxyUwU`
There are many places that join path segments with `::` to produce a
string. A lot of these use `join("::")`. Many in rustdoc use
`join_with_double_colon`, and a few use `.joined("..")`. One in Clippy
uses `itertools::join`. A couple of them look for `kw::PathRoot` in the
first segment, which can be important.
This commit introduces `rustc_ast::join_path_{syms,ident}` to do the
joining for everyone. `rustc_ast` is as good a location for these as
any, being the earliest-running of the several crates with a `Path`
type. Two functions are needed because `Ident` printing is more complex
than simple `Symbol` printing.
The commit also removes `join_with_double_colon`, and
`estimate_item_path_byte_length` with it.
There are still a handful of places that join strings with "::" that are
unchanged. They are not that important: some of them are in tests, and
some of them first split a path around "::" and then rejoin with "::".
This fixes one test case where `{{root}}` shows up in an error message.
Add tracing to `InterpCx::fn_abi_of_instance/fn_abi_of_fn_ptr`
This PR adds tracing to the `InterpCx::fn_abi_of_instance`/`::fn_abi_of_fn_ptr` functions by shadowing `FnAbiOf`'s trait methods with inherent methods on `InterpCx`, like done in rust-lang/rust#142721. The reason why I am targeting these two functions is because they are used for Miri interpretation, and they make a `layout_of` query down the line without passing through the `layout_of` that was traced in rust-lang/rust#142721.
There are other places where `layout_of` is called without being traced (see the analysis below), but that's because the `Machine` used there is not `MiriMachine` but rather `CompileTimeMachine` which does not implement `enter_trace_span()`. But after discussing with ```````@RalfJung``````` we agreed that the const-eval part should not be traced together with Miri, that's why I am ignoring the other places where `layout_of` is called.
r? ```````@RalfJung```````
<details><summary>Analysis of the places where <code>layout_of</code> is called</summary>
I did some analysis for https://github.com/rust-lang/rust/pull/142721#discussion_r2171494841, and these are all the places where the query `tcx.layout_of` is called (directly or indirectly) outside of a traced `InterpCx::layout_of` while a program is being interpreted by Miri:
```
adjust_for_rust_scalar at ./compiler/rustc_ty_utils/src/abi.rs:302:35
{closure#2} at ./compiler/rustc_ty_utils/src/abi.rs:522:25
eval_body_using_ecx<> at ./compiler/rustc_const_eval/src/const_eval/eval_queries.rs:49:22
{closure#1}<> at ./compiler/rustc_const_eval/src/interpret/operand.rs:851:76
{closure#0}<> at ./compiler/rustc_const_eval/src/interpret/stack.rs:612:18
size_and_align at ./compiler/rustc_middle/src/mir/interpret/mod.rs:387:38
```
I got these by:
- patching rustc with this patch that adds a span to the `layout_of` query which prints the backtrace:
[layout_of_other_places.diff.txt](https://github.com/user-attachments/files/21235523/layout_of_other_places.diff.txt)
- adding this to my bootstrap.toml to have debug symbols inside the Miri binary: `rust.debuginfo-level = "line-tables-only"` and also `build.tool.miri.features = ["tracing"]`
- obtaining a trace file with `MIRI_TRACING=1 ./x.py run miri --stage 1 --warnings warn --args src/tools/miri/tests/pass/hello.rs` (note: maybe using a file different than "src/tools/miri/tests/pass/hello.rs" would lead to more places where layout_of is called?)
- running this query in Perfetto to select all `layout_of` spans that have as a direct parent a span named "frame" (as opposed to the parent being `InterpCx::layout_of`) and extract their backtrace: `select args.string_value from slice left join args on slice.arg_set_id = args.id where slice.name = "tcx.layout_of" and slice.parent_id in (select slice2.id from slice as slice2 where slice2.name = "frame") group by args.string_value`
- exporting the data as `.tsv` and processing that file through this Python script. It finds the first path in the backtraces where "layout" isn't mentioned, which imo is a good heuristic to not consider `layout_of` wrappers/friends as call places, but rather go down the backtrace until an actual call place is reached. [layout_of_other_places.py.txt](https://github.com/user-attachments/files/21235529/layout_of_other_places.py.txt)
</details>
tidy: check for invalid file names
Check for file names added to git with:
- non-UTF8 filenames (this would fail "fmt check" with a decoding error for the moment, but maybe we should not count on it as it is an accidental failure)
- control characters (such as "\n" or "\r" in file names)
- ":" (which is a special character on Windows, made rust-lang/rust#142936 fail in bors while it could have be caught earlier)
It only checks files known by git as a developer might want to have "strange" file names alongside their local repository as long as they don't check them in.
r? jieyouxu
as he stumbled upon such a file in rust-lang/rust#142936
remote-test-client: Exit code `128 + <signal-number>` instead of `3`
If the remote process is terminated by a signal, make `remote-test-client` exit with the code `128 + <signal-number>` instead of always `3`. This follows common practice among tools such as bash [^1]:
> When a command terminates on a fatal signal whose number is N, Bash uses the
> value 128+N as the exit status.
It also allows us to differentiate between `run-pass` and `run-crash` ui tests without special case code in compiletest for that when `remote-test-client` is used. See https://github.com/rust-lang/rust/pull/143002 and in particular https://github.com/rust-lang/rust/pull/143002#issuecomment-3037061667.
Exiting with code `3` has been done from the start (see https://github.com/rust-lang/rust/pull/39400) and seems arbitrary rather than a deliberate design decision, so changing it does not seem like an extraordinarily big deal.
### Regression testing
Note that https://github.com/rust-lang/rust/pull/143002 will act as a regression test once it is rebased on this PR.
### Why a separate PR
I think it is comforting to know that CI does not break with just this change. But if my reviewer prefers, we can move this commit to be part of https://github.com/rust-lang/rust/pull/143002 instead.
[^1]: https://www.gnu.org/software/bash/manual/html_node/Exit-Status.html
rustdoc-json: Structured attributes
Implements and closesrust-lang/rust#141358.
This has 2 primary benefits.
1. For rustdoc-json consumers, they no longer need to parse strings of attributes, but it's there in a structured and normalized way. CC ```@obi1kenobi```
2. For rustc conributors, the output of HIR pretty printing is no longer a versioned thing in the output. People can work on rust-lang/rust#131229 without needing to bump `FORMAT_VERSION`. CC ```@jdonszelmann``` ```@JonathanBrouwer.```
(Over time, as the attribute refractor continues, I expect we'll add new things to `rustdoc_json_types::Attribute`. But this can be done separately to the rustc changes).
Todo before being mergable:
- [x] Update test assertions.
- [x] Fix modeling of `#[repr]`.
- [ ] ~~Add tests of `#[doc(hidden)]` in `Item::attrs` (probably in a seperate PR).~~ I'm gonna punt this to a future PR
- [x] Documentation.
Implements https://www.github.com/rust-lang/rust/issues/141358.
This has 2 primary benefits:
1. For rustdoc-json consumers, they no longer need to parse strings of
attributes, but it's there in a structured and normalized way.
2. For rustc contributors, the output of HIR pretty printing is no
longer a versioned thing in the output. People can work on
https://github.com/rust-lang/rust/issues/131229 without needing to
bump `FORMAT_VERSION`.
(Over time, as the attribute refractor continues, I expect we'll add new
things to `rustdoc_json_types::Attribute`. But this can be done
separately to the rustc changes).
Instead of making this a build parameter, pass the SCRIPT as an
environment variable.
To this purpose, normalize on always referring to a script in
`/scripts`.
For i686-gnu-nopt-2 I had to create a separate script, because
Docker seems to be really terrible at command line argument
parsing, so it's not possible to pass an environment variable that
contains whitespace.
Includes a custom syntax shortand to enter_trace_span! with NAME::SUBNAME.
MaybeEnteredTraceSpan is `pub use`d in lib.rs to make it available also in bin/, just in case.
Update books
## rust-lang/book
3 commits in ef1ce8f87a8b18feb1b6a9cf9a4939a79bde6795..b2d1a0821e12a676b496d61891b8e3d374a8e832
2025-07-08 17:24:41 UTC to 2025-07-02 21:30:57 UTC
- Chapter 16 from tech review (rust-lang/book#4438)
- WIP ch 17 edits after tech review (rust-lang/book#4319)
- Chapter 15 from tech review (rust-lang/book#4433)
## rust-embedded/book
1 commits in 41f688a598a5022b749e23d37f3c524f6a0b28e1..fe88fbb68391a465680dd91109f0a151a1676f3e
2025-07-08 18:54:25 UTC to 2025-07-08 18:54:25 UTC
- Clarify usage of #[interrupt] attribute and recommend device crate re… (rust-embedded/book#386)
## rust-lang/nomicon
3 commits in 8b61acfaea822e9ac926190bc8f15791c33336e8..3ff384320598bbe8d8cfe5cb8f18f78a3a3e6b15
2025-07-05 07:34:22 UTC to 2025-07-05 07:13:51 UTC
- Add build script part to FFI chapter for more clear and smooth learn … (rust-lang/nomicon#440)
- Cleanups for tree example of splitting borrows (rust-lang/nomicon#443)
- Handle drop zst (rust-lang/nomicon#425)
## rust-lang/reference
17 commits in e9fc99f107840813916f62e16b3f6d9556e1f2d8..1f45bd41fa6c17b7c048ed6bfe5f168c4311206a
2025-07-11 23:15:51 UTC to 2025-07-01 16:49:33 UTC
- mention an important use for the naked attribute (rust-lang/reference#1929)
- Array expression repeat operands can be const blocks. (rust-lang/reference#1928)
- Document (tuple) struct pattern namespace behavior (rust-lang/reference#1925)
- Replace set of en dashes with set of em dashes (rust-lang/reference#1926)
- Update `should_panic` to use the attribute template (rust-lang/reference#1882)
- const-eval.const-expr.borrows: mention indirect places (rust-lang/reference#1865)
- associated-items.md: remove redundant word (rust-lang/reference#1874)
- introduction.md: replace hard-to-read example (rust-lang/reference#1873)
- typo (rust-lang/reference#1924)
- Update `ignore` to use the attribute template (rust-lang/reference#1881)
- Update `test` to use the attribute template (rust-lang/reference#1880)
- Update `cfg_attr` to use the attribute template (rust-lang/reference#1879)
- Update `cfg` to use the attribute template (rust-lang/reference#1878)
- allow constants to refer to mutable/external memory, but reject such constants as patterns (rust-lang/reference#1859)
- Remove outdated comment about non-copy unions (rust-lang/reference#1872)
- Add a template for documenting attributes (rust-lang/reference#1877)
- Switch enum grammar to use "variant" (rust-lang/reference#1876)
## rust-lang/rust-by-example
1 commits in 288b4e4948add43f387cad35adc7b1c54ca6fe12..e386be5f44af711854207c11fdd61bb576270b04
2025-07-04 23:17:15 UTC to 2025-07-04 23:17:15 UTC
- Update Chinese translations (rust-lang/rust-by-example#1943)
Adjust `run_make_support::symbols` helpers
Massage the `symbols` helpers to fill out {match all, match any} x {substring match, exact match}:
| | Substring match | Exact match |
|-----------|----------------------------------------|-------------------------------|
| Match any | `object_contains_any_symbol_substring` | `object_contains_any_symbol` |
| Match all | `object_contains_all_symbol_substring` | `object_contains_all_symbols` |
As I'd like to use `object_contains_all_symbols` for rust-lang/rust#143669.
As part of this:
- Rename `any_symbol_contains` to `object_contains_any_symbol_substring` for accuracy, as `any_symbol_contains` is actually "contains any matching substring".
- Remove `with_symbol_iter`.
Noticed while working on https://github.com/rust-lang/rust/pull/143669.
r? ``@ChrisDenton`` (or compiler)
Don't panic if WASI_SDK_PATH not set when detecting compiler
The fedora packaging builds the wasm sysroot outside of the rust build system. Fedora applies a couple of patches related to wasm which I think make this possible. Not panicking seems consistent with the detection logic of other targets when they cannot find cc.
Drop `./x suggest`
This PR removes the current `./x suggest` implementation (rust-lang/rust#109933, rust-lang/rust#106249) and associated docs for several reasons:
1. Primarily, `./x suggest` is another "flow" in bootstrap that incurs extra complexity and more invariants that bootstrap has to maintain. This causes more friction when trying to investigate and fix staging problems. As far as I know, this flow has not been actively maintained in quite a while, and I'm not aware of interest in maintaining it. Bootstrap really could use less implementation complexity with a very limited maintenance bandwidth.
2. The current `./x suggest` implementation "bypasses" the usual stage defaults for the various check/build/test/etc. flows, and it's not really possible to have a stage default because `./x suggest --run` produces a *sequence* of suggestions like [`./x check`, `./x test library/std`, ..] and then tries to run all of them in sequence, based on which files are modified.
3. We've not seen a lot of interest both in using it or extending static/dynamic test suggestions. Last extensions were rust-lang/rust#117961 and rust-lang/rust#120763. I'm not convinced the extra implementation complexity is worth it. This was discussed in:
- [#t-infra/bootstrap > Dropping the current `./x suggest` flow implementation](https://rust-lang.zulipchat.com/#narrow/channel/326414-t-infra.2Fbootstrap/topic/Dropping.20the.20current.20.60.2E.2Fx.20suggest.60.20flow.20implementation/with/527456699)
- [#t-compiler > Dropping current `./x suggest` implementation](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Dropping.20current.20.60.2E.2Fx.20suggest.60.20implementation/with/527528696)
Closesrust-lang/rust#109933 (the current implementation is being removed).
Closesrust-lang/rust#143569 (by removing `./x suggest` altogether).
