Rollup merge of #84101 - jyn514:early-pass, r=Manishearth
rustdoc: Move crate loader to collect_intra_doc_links::early
This groups the similar code together, and also allows making most of collect_intra_doc_links private again.
This builds on https://github.com/rust-lang/rust/pull/84066, but it wouldn't be too hard to base it off master if you want this to land first.
Helps with https://github.com/rust-lang/rust/issues/83761.
Rollup merge of #84067 - rust-lang:steveklabnik-patch-1, r=joshtriplett
clean up example on read_to_string
This is the same thing, but simpler.
This came out of a comment from a user: https://news.ycombinator.com/item?id=25318117 but rather than hide the signature of main, I think a `use` plus not including the `'static` makes more sense.
Rollup merge of #84059 - zvirja:update-libc, r=JohnTitor
Bump libc dependency of std to 0.2.93
Update `libc` dependency of `std` to the latest version. That allows to consume the https://github.com/rust-lang/libc/pull/2131 fix and fix build for the `mipsel-unknown-linux-uclibc` target.
Rollup merge of #84014 - estebank:cool-bears-hot-tip, r=varkor
Improve trait/impl method discrepancy errors
* Use more accurate spans
* Clean up some code by removing previous hack
* Provide structured suggestions
Structured suggestions are particularly useful for cases where arbitrary self types are used, like in custom `Future`s, because the way to write `self: Pin<&mut Self>` is not necessarily self-evident when first encountered.
Rollup merge of #83669 - kwj2104:issue-81508-fix, r=varkor
Issue 81508 fix
Fix #81508
**Problem**: When variable name is used incorrectly as path, error and warning point to undeclared/unused name, when in fact the name is used, just incorrectly (should be used as a variable, not part of a path).
**Summary for fix**: When path resolution errs, diagnostics checks for variables in ```ValueNS``` that have the same name (e.g., variable rather than path named Foo), and adds additional suggestion that user may actually intend to use the variable name rather than a path.
The fix does not suppress or otherwise change the *warning* that results. I did not find a straightforward way in the code to modify this, but would love to make changes here as well with any guidance.
Allow using `-C force-unwind-tables=no` when `panic=unwind`
It seems LLVM still generates proper unwind tables even there is no `uwtable` attribute, unless I looked at the wrong place :thinking::
https://github.com/llvm/llvm-project/blob/c21016715f0ee4a36affdf7150ac135ca98b0eae/llvm/include/llvm/IR/Function.h#L666
Therefore, I *assume* it's safe to omit `uwtable` even when `panic=unwind`, and this PR removes the restriction that disallows using `-C force-unwind-tables=no` when `panic=unwind`.
Auto merge of #81469 - tweksteen:android_set_message, r=m-ou-se
android: set abort message
Android has the ability to supply an abort message [1]. This message is
automatically included in the debug trace, which helps debugging [2].
Modify panic_abort to populate this message before calling abort().
Add note about reverting a workaround in the future
The root cause was fixed upstream in LLVM main. This adds a reminder to revert the workaround once the LLVM rustc depends on is new enough. Since I'm not sure how such optimizations get routed to LLVM releases, I used the conservative assumption that it will only show up with LLVM 13.
Auto merge of #82608 - Aaron1011:feature/final-preexp-tts, r=petrochenkov
Implement token-based handling of attributes during expansion
This PR modifies the macro expansion infrastructure to handle attributes
in a fully token-based manner. As a result:
* Derives macros no longer lose spans when their input is modified
by eager cfg-expansion. This is accomplished by performing eager
cfg-expansion on the token stream that we pass to the derive
proc-macro
* Inner attributes now preserve spans in all cases, including when we
have multiple inner attributes in a row.
This is accomplished through the following changes:
* New structs `AttrAnnotatedTokenStream` and `AttrAnnotatedTokenTree` are introduced.
These are very similar to a normal `TokenTree`, but they also track
the position of attributes and attribute targets within the stream.
They are built when we collect tokens during parsing.
An `AttrAnnotatedTokenStream` is converted to a regular `TokenStream` when
we invoke a macro.
* Token capturing and `LazyTokenStream` are modified to work with
`AttrAnnotatedTokenStream`. A new `ReplaceRange` type is introduced, which
is created during the parsing of a nested AST node to make the 'outer'
AST node aware of the attributes and attribute target stored deeper in the token stream.
* When we need to perform eager cfg-expansion (either due to `#[derive]` or `#[cfg_eval]`), we tokenize and reparse our target, capturing additional information about the locations of `#[cfg]` and `#[cfg_attr]` attributes at any depth within the target. This is a performance optimization, allowing us to perform less work in the typical case where captured tokens never have eager cfg-expansion run.
Aaron Hill [Sat, 28 Nov 2020 23:33:17 +0000 (18:33 -0500)]
Implement token-based handling of attributes during expansion
This PR modifies the macro expansion infrastructure to handle attributes
in a fully token-based manner. As a result:
* Derives macros no longer lose spans when their input is modified
by eager cfg-expansion. This is accomplished by performing eager
cfg-expansion on the token stream that we pass to the derive
proc-macro
* Inner attributes now preserve spans in all cases, including when we
have multiple inner attributes in a row.
This is accomplished through the following changes:
* New structs `AttrAnnotatedTokenStream` and `AttrAnnotatedTokenTree` are introduced.
These are very similar to a normal `TokenTree`, but they also track
the position of attributes and attribute targets within the stream.
They are built when we collect tokens during parsing.
An `AttrAnnotatedTokenStream` is converted to a regular `TokenStream` when
we invoke a macro.
* Token capturing and `LazyTokenStream` are modified to work with
`AttrAnnotatedTokenStream`. A new `ReplaceRange` type is introduced, which
is created during the parsing of a nested AST node to make the 'outer'
AST node aware of the attributes and attribute target stored deeper in the token stream.
* When we need to perform eager cfg-expansion (either due to `#[derive]` or `#[cfg_eval]`),
we tokenize and reparse our target, capturing additional information about the locations of
`#[cfg]` and `#[cfg_attr]` attributes at any depth within the target.
This is a performance optimization, allowing us to perform less work
in the typical case where captured tokens never have eager cfg-expansion run.
Auto merge of #84071 - nagisa:nixos-patching-fix, r=Mark-Simulacrum
Fix NixOS patching
Moving the `.nix-deps` has resulted in rpath links being broken and
therefore bootstrap on NixOS broken entirely.
This PR still produces a `.nix-deps` but only for the purposes of
producing a gc root. We rpath a symlink-resolved result instead.
For purposes of simplicity we also use joinSymlink to produce a single
merged output directory so that we don't need to update multiple
locations every time we add a library or something.
Fixes a regression from https://github.com/rust-lang/rust/pull/82739.
The lint used to be called `non-autolinks`, and linted more than just
bare URLs. Now, it is called `bare-urls` and only lints against bare
URLs. So, `bare-urls` is a better name for the test.
Moving the `.nix-deps` has resulted in rpath links being broken and
therefore bootstrap on NixOS broken entirely.
This PR still produces a `.nix-deps` but only for the purposes of
producing a gc root. We rpath a symlink-resolved result instead.
For purposes of simplicity we also use joinSymlink to produce a single
merged output directory so that we don't need to update multiple
locations every time we add a library or something.
Add note about reverting a workaround in the future
The root cause was fixed upstream in LLVM main. This adds a reminder to revert the workaround once the LLVM rustc depends on is new enough. Since I'm not sure how such optimizations get routed to LLVM releases, I used the conservative assumption that it will only show up with LLVM 13.
Auto merge of #84052 - RalfJung:libcore-miri, r=Mark-Simulacrum
fix Miri errors in libcore doctests
Now that Miri can run doctests, it found some issues in the libcore doctests:
* The `AtomicPtr` tests accessed dangling memory! `AtomicPtr::new(&mut 10);` makes the `10` a temporary that is deallocated after the end of this expression.
* The tests for `set_ptr_value` used `&array[0] as *const _` to get a pointer to the array; this needs to be `array.as_ptr()` instead (Cc https://github.com/rust-lang/unsafe-code-guidelines/issues/134).
* I reduced a buffer size in a `MaybeUninit` test to make it less slow in Miri, and added a spin loop hint to fix a diverging loop in Miri.
Auto merge of #84055 - kornelski:z-edition, r=petrochenkov
Don't tell users to use a nightly flag on the stable channel
When a crate requires a newer edition, currently rustc tells users to use `-Z unstable-options`. This is not ideal, because:
* This flag doesn't work on the stable channel, so solution to one error only causes another error, which is frustrating.
* Directs users towards the nightly channel, which is not necessarily the correct solution. Once the next edition is released, this message will be mostly seen by users of out-of-date stable Rust versions who merely need to update their Rust to the latest stable.
Auto merge of #84024 - estebank:unclosed-brace-use, r=jackh726
Avoid `;` -> `,` recovery and unclosed `}` recovery from being too verbose
Those two recovery attempts have a very bad interaction that causes too
unnecessary output. Add a simple gate to avoid interpreting a `;` as a
`,` when there are unclosed braces.
Auto merge of #84004 - mattico:print-target-features-improvements, r=petrochenkov
Categorize and explain target features support
There are 3 different uses of the `-C target-feature` args passed to rustc:
1. All of the features are passed to LLVM, which uses them to configure code-generation. This is sort-of stabilized since 1.0 though LLVM does change/add/remove target features regularly.
2. Target features which are in [the compiler's allowlist](https://github.com/rust-lang/rust/blob/69e1d22ddbc67b25141a735a22a8895a678b32ca/compiler/rustc_codegen_ssa/src/target_features.rs#L12-L34) can be used in `cfg!(target_feature)` etc. These may have different names than in LLVM and are renamed before passing them to LLVM.
3. Target features which are in the allowlist and which are stabilized or feature-gate-enabled can be used in `#[target_feature]`.
It can be confusing that `rustc --print target-features` just prints out the LLVM features without separating out the rustc features or even mentioning that the dichotomy exists.
This improves the situation by separating out the rustc and LLVM target features and adding a brief explanation about the difference.
Abbreviated Example Output:
```
$ rustc --print target-features
Features supported by rustc for this target:
adx - Support ADX instructions.
aes - Enable AES instructions.
...
xsaves - Support xsaves instructions.
crt-static - Enables libraries with C Run-time Libraries(CRT) to be statically linked.
Code-generation features supported by LLVM for this target:
16bit-mode - 16-bit mode (i8086).
32bit-mode - 32-bit mode (80386).
...
x87 - Enable X87 float instructions.
xop - Enable XOP instructions.
Use +feature to enable a feature, or -feature to disable it.
For example, rustc -C target-cpu=mycpu -C target-feature=+feature1,-feature2
Code-generation features cannot be used in cfg or #[target_feature],
and may be renamed or removed in a future version of LLVM or rustc.
```
Motivated by #83975.
CC https://github.com/rust-lang/rust/issues/49653
Avoid `;` -> `,` recovery and unclosed `}` recovery from being too verbose
Those two recovery attempts have a very bad interaction that causes too
unnecessary output. Add a simple gate to avoid interpreting a `;` as a
`,` when there are unclosed braces.
Auto merge of #81942 - the8472:reduce-ui-test-threads, r=Mark-Simulacrum
reduce threads spawned by ui-tests
The test harness already spawns enough tests to keep all cores busy.
Individual tests should keep their own threading to a minimum to avoid context switch overhead.
When running ui tests with lld enabled this shaves about 10% off that testsuite on my machine.
Auto merge of #84030 - jyn514:no-blanket-impls, r=GuillaumeGomez
rustdoc: Don't generate blanket impls when running --show-coverage
`get_blanket_impls` is the slowest part of rustdoc, and the coverage pass
completely ignores blanket impls. This stops running it at all, and also
removes some unnecessary checks in `calculate_doc_coverage` that ignored
the impl anyway.
We don't currently measure --show-coverage in perf.rlo, but I tested
this locally on cargo and it brought the time down from 2.9 to 1.6
seconds.
This also adds back a commented-out test; Rustdoc has been able to deal with `impl trait` for almost a year now.
Android has the ability to supply an abort message [1]. This message is
automatically included in the debug trace, which helps debugging [2].
Modify panic_abort to populate this message before calling abort().
Joshua Nelson [Fri, 9 Apr 2021 13:00:12 +0000 (09:00 -0400)]
rustdoc: Don't generate blanket impls when running --show-coverage
get_blanket_impls is the slowest part of rustdoc, and the coverage pass
completely ignores blanket impls. This stops running it at all, and also
removes some unnecessary checks in `calculate_doc_coverage` that ignored
the impl anyway.
We don't currently measure --show-coverage in perf.rlo, but I tested
this locally on cargo and it brought the time down from 2.9 to 1.6
seconds.
The8472 [Fri, 26 Mar 2021 18:01:55 +0000 (19:01 +0100)]
reduce threads spawned by ui-tests
the test harness already spawns enough tests for all cores, individual
tests should keep their own threading to a minimum to avoid context switch
overhead
some tests fail with 1 CGU, so explicit compile flags have been added
to keep their old behavior
Auto merge of #83870 - jackh726:binder-refactor-fix, r=nikomatsakis
Don't concatenate binders across types
Partially addresses #83737
There's actually two issues that I uncovered in #83737. The first is that we are concatenating bound vars across types, i.e. in
```
F: Fn(&()) -> &mut (dyn Future<Output = ()> + Unpin)
```
the bound vars on `Future` get set as `for<anon>` since those are the binders on `Fn(&()`. This is obviously wrong, since we should only concatenate directly nested trait refs. This is solved here by introducing a new `TraitRefBoundary` scope, that we put around the "syntactical" trait refs and basically don't allow concatenation across.
Now, this alone *shouldn't* be a super terrible problem. At least not until you consider the other issue, which is a much more elusive and harder to design a "perfect" fix. A repro can be seen in:
```
use core::future::Future;
async fn handle<F>(slf: &F)
where
F: Fn(&()) -> &mut (dyn for<'a> Future<Output = ()> + Unpin),
{
(slf)(&()).await;
}
```
Notice the `for<'a>` around `Future`. Here, `'a` is unused, so the `for<'a>` Binder gets changed to a `for<>` Binder in the generator witness, but the "local decl" still has it. This has heavy intersections with region anonymization and erasing. Luckily, it's not *super* common to find this unique set of circumstances. It only became apparently because of the first issue mentioned here. However, this *is* still a problem, so I'm leaving #83737 open.
Auto merge of #83941 - wesleywiser:win_dbginfo_closures, r=nagisa
Improve debuginfo for closures and async functions on Windows MSVC
The issue was that the resulting debuginfo was too complex for LLVM to
translate into CodeView records correctly. As a result, it simply
ignored the debuginfo which meant Windows debuggers could not display
any closed over variables when stepping inside a closure or async fn.
This fixes that by creating additional allocas on the stack so that
the resulting debuginfo is simple (just `*my_variable.dbg.spill`) and
LLVM can generate the correct CV records.
I also updated some of our existing tests to run in CDB to cover this case.
Rollup merge of #83992 - GuillaumeGomez:merge-idents, r=notriddle
Merge idents when generating source content
The idea here is to not have a span for each part of a path. Currently, for `a::b::c` we generate `<span>a</span>::<span>b</span>::<span>c</span>`, with this change, we will generate `<span>a::b::c</span>`.
A nice "side-effect" is that it reduces the size of the output HTML too. :)
Rollup merge of #81938 - lukaslueg:stab_peek_mut, r=Amanieu
Stabilize `peekable_peek_mut`
Resolves #78302. Also adds some documentation on `std::iter::Iterator::peekable()` regarding the new method.
The feature was added in #77491 in Nov' 20, which is recently, but the feature seems reasonably small. Never did a stabilization-pr, excuse my ignorance if there is a protocol I'm not aware of.
Rollup merge of #80733 - steffahn:prettify_pin_links, r=jyn514
Improve links in inline code in `core::pin`.
## Context
So I recently opened #80720. That PR uses HTML-based `<code>foo</code>` syntax in place of `` `foo` `` for some inline code. It looks like usage of `<code>` tags in doc comments is without precedent in the standard library, but the HTML-based syntax has an important advantage:
You can write something like
```
<code>[Box]<[Option]\<T>></code>
```
which becomes: <code>[Box]<[Option]\<T>></code>, whereas with ordinary backtick syntax, you cannot create links for a substring of an inline code block.
## Problem
I recalled (from my own experience) that a way to partially work around this limitation is to do something like
```
[`Box`]`<`[`Option`]`<T>>`
```
which looks like this: [`Box`]`<`[`Option`]`<T>>` _(admitted, it looks even worse on GitHub than in `rustdoc`’s CSS)_.
So I searched the standard library and found that e.g. the [std::pin](https://doc.rust-lang.org/std/pin/index.html) module documentation uses this hack/workaround quite a bit, with types like <code>[Pin]<[Box]\<T>></code> or <code>[Pin]<[&mut] T>></code>. Although the way they look like in this sentence is what I would like them to look like, not what they currently look.
### Status Quo
Here’s a screenshot of what it currently looks like:
With a few HTML-style code blocks, we can fix all the spacing issues in the above screenshot that are due usage of this hack/workaround of putting multiple code blocks right next to each other being used.
There’s still a problem of inconsistency. Especially in a sentence such as
> A [`Pin<P>`][Pin] where `P: Deref` should be considered as a "`P`-style pointer" to _[...]_
looks weird with the variable `P` having different colors (and `Deref` has a different color from before where it was a link, too). Or compare the difference of <code>[Pin]<[Box]\<T>></code> vs [`Box<T>`][Box] where one time the variable is part of the link and the other time it isn’t.
_Note: Color differences show even **more strongly** when the ayu theme is used, while they are a bit less prominent in the light theme than they are in the dark theme, which is the one used for these screenshots._
This is why I’ve added the next commit
### after ceaeb249a3813a78bd81fa3890e27e8843a58262
pulling all the type parameters out of their links, and also the last commit with clearly visible changes
### after 87ac118ba3d0c8268e043fadbd63b51e06904795
where more links are added, removing e.g. the inconsistency with `Deref`’s color in e.g. `P: Deref` that I already mentioned above.
## Discussion
I am aware that this PR may very well be overkill. If for now only the first commit (plus the fix for the `Drop` link in e65385fbfa72995b27ec64aa54f330cf503dfc03, the link titles 684edf7a70d2e90466ae74e7a321670259bf3fd9 as far as they apply, and a few of the line-break changes) are wanted, I can reduce this PR to just those changes. I personally find the rendered result with all these changes very nice though. On the other hand, all these `<code>` tags are not very nice in the source code, I’ll admit.
Perhaps alternative solutions could be preferred, such as `rustdoc` support for merging subsequent inline code blocks so that all the cases that currently use workarounds rendered as [`Box`]`<`[`Option`]`<T>>` automatically become <code>[Box]<[Option]\<T>></code> without any need for further changes. Even in this case, having a properly formatted, better looking example in the standard library docs could help motivate such a change to `rustdoc` by prodiving an example of the expected results and also the already existing alternative (i.e. using `<code>`). On the other hand, `` [`Box`]`<`[`Option`]`<T>>` `` isn’t particularly nice-looking source code either. I’m not even sure if I wouldn’t actually find the version `<code>[Box]<[Option]\<T>></code>` cleaner to read.
Fix closed over variables not available in debuginfo for Windows MSVC
The issue was that the resulting debuginfo was too complex for LLVM to
translate into CodeView records correctly. As a result, it simply
ignored the debuginfo which meant Windows debuggers could not display
any closed over variables when stepping inside a closure.
This fixes that by spilling additional variables to the stack so that
the resulting debuginfo is simple (just `*my_variable.dbg.spill`) and
LLVM can generate the correct CV records.
Auto merge of #83763 - alexcrichton:wasm-multivalue-abi, r=nagisa
rustc: Add a new `wasm` ABI
This commit implements the idea of a new ABI for the WebAssembly target,
one called `"wasm"`. This ABI is entirely of my own invention
and has no current precedent, but I think that the addition of this ABI
might help solve a number of issues with the WebAssembly targets.
When `wasm32-unknown-unknown` was first added to Rust I naively
"implemented an abi" for the target. I then went to write `wasm-bindgen`
which accidentally relied on details of this ABI. Turns out the ABI
definition didn't match C, which is causing issues for C/Rust interop.
Currently the compiler has a "wasm32 bindgen compat" ABI which is the
original implementation I added, and it's purely there for, well,
`wasm-bindgen`.
Another issue with the WebAssembly target is that it's not clear to me
when and if the default C ABI will change to account for WebAssembly's
multi-value feature (a feature that allows functions to return multiple
values). Even if this does happen, though, it seems like the C ABI will
be guided based on the performance of WebAssembly code and will likely
not match even what the current wasm-bindgen-compat ABI is today. This
leaves a hole in Rust's expressivity in binding WebAssembly where given
a particular import type, Rust may not be able to import that signature
with an updated C ABI for multi-value.
To fix these issues I had the idea of a new ABI for WebAssembly, one
called `wasm`. The definition of this ABI is "what you write
maps straight to wasm". The goal here is that whatever you write down in
the parameter list or in the return values goes straight into the
function's signature in the WebAssembly file. This special ABI is for
intentionally matching the ABI of an imported function from the
environment or exporting a function with the right signature.
With the addition of a new ABI, this enables rustc to:
* Eventually remove the "wasm-bindgen compat hack". Once this multivalue
ABI is stable wasm-bindgen can switch to using it everywhere.
Afterwards the wasm32-unknown-unknown target can have its default ABI
updated to match C.
* Expose the ability to precisely match an ABI signature for a
WebAssembly function, regardless of what the C ABI that clang chooses
turns out to be.
* Continue to evolve the definition of the default C ABI to match what
clang does on all targets, since the purpose of that ABI will be
explicitly matching C rather than generating particular function
imports/exports.
Naturally this is implemented as an unstable feature initially, but it
would be nice for this to get stabilized (if it works) in the near-ish
future to remove the wasm32-unknown-unknown incompatibility with the C
ABI. Doing this, however, requires the feature to be on stable because
wasm-bindgen works with stable Rust.
Alex Crichton [Thu, 1 Apr 2021 23:08:29 +0000 (16:08 -0700)]
rustc: Add a new `wasm` ABI
This commit implements the idea of a new ABI for the WebAssembly target,
one called `"wasm"`. This ABI is entirely of my own invention
and has no current precedent, but I think that the addition of this ABI
might help solve a number of issues with the WebAssembly targets.
When `wasm32-unknown-unknown` was first added to Rust I naively
"implemented an abi" for the target. I then went to write `wasm-bindgen`
which accidentally relied on details of this ABI. Turns out the ABI
definition didn't match C, which is causing issues for C/Rust interop.
Currently the compiler has a "wasm32 bindgen compat" ABI which is the
original implementation I added, and it's purely there for, well,
`wasm-bindgen`.
Another issue with the WebAssembly target is that it's not clear to me
when and if the default C ABI will change to account for WebAssembly's
multi-value feature (a feature that allows functions to return multiple
values). Even if this does happen, though, it seems like the C ABI will
be guided based on the performance of WebAssembly code and will likely
not match even what the current wasm-bindgen-compat ABI is today. This
leaves a hole in Rust's expressivity in binding WebAssembly where given
a particular import type, Rust may not be able to import that signature
with an updated C ABI for multi-value.
To fix these issues I had the idea of a new ABI for WebAssembly, one
called `wasm`. The definition of this ABI is "what you write
maps straight to wasm". The goal here is that whatever you write down in
the parameter list or in the return values goes straight into the
function's signature in the WebAssembly file. This special ABI is for
intentionally matching the ABI of an imported function from the
environment or exporting a function with the right signature.
With the addition of a new ABI, this enables rustc to:
* Eventually remove the "wasm-bindgen compat hack". Once this
ABI is stable wasm-bindgen can switch to using it everywhere.
Afterwards the wasm32-unknown-unknown target can have its default ABI
updated to match C.
* Expose the ability to precisely match an ABI signature for a
WebAssembly function, regardless of what the C ABI that clang chooses
turns out to be.
* Continue to evolve the definition of the default C ABI to match what
clang does on all targets, since the purpose of that ABI will be
explicitly matching C rather than generating particular function
imports/exports.
Naturally this is implemented as an unstable feature initially, but it
would be nice for this to get stabilized (if it works) in the near-ish
future to remove the wasm32-unknown-unknown incompatibility with the C
ABI. Doing this, however, requires the feature to be on stable because
wasm-bindgen works with stable Rust.
projects / rust.git / log