Mara Bos [Wed, 30 Dec 2020 20:56:54 +0000 (20:56 +0000)]
Rollup merge of #80488 - CAD97:drop-weak-without-reference, r=m-ou-se
Do not create dangling &T in Weak<T>::drop
Since at this point all strong pointers have been dropped, the wrapped `T` has also been dropped. As such, creating a `&T` to the dropped place is negligent at best (language UB at worst). Since we have `Layout::for_value_raw` now, use that instead of `Layout::for_value` to avoid creating the `&T`.
This does have implications for custom (potentially thin) DSTs, though much less severe than those discussed in #80407. Specifically, one of two things has to be true:
- It has to be possible to use a `*const T` to a dropped (potentially custom, potentially thin) unsized tailed object to determine the layout (size/align) of the object. This is what is currently implemented (though with `&T` instead of `&T`). The validity of reading some location after it has been dropped is an open question IIUC (https://github.com/rust-lang/unsafe-code-guidelines/issues/188) (except when the whole type is `Copy`, per `drop_in_place`'s docs).
In this design, custom DSTs would get a `*mut T` and use that to return layout, and must be able to do so while in the "zombie" (post-drop, pre-free) state.
- `RcBox`/`ArcInner` compute and store layout eagerly, so that they don't have to ask the type for its layout after dropping it.
Importantly, this is already true today, as you can construct `Rc<DST>`, create a `Weak<DST>`, and drop the `Rc` before the `Weak`. This PR is a strict improvement over the status quo, and the above question about potentially thin DSTs will need to be resolved by any custom DST proposal.
Mara Bos [Wed, 30 Dec 2020 20:56:52 +0000 (20:56 +0000)]
Rollup merge of #80458 - RalfJung:promotion-refactor, r=oli-obk
Some Promotion Refactoring
Clean up promotion a bit:
* factor out some common code
* more exhaustive matches
This *should* not break anything... the only potentially-breaking change is that `BorrowKind::Shallow | BorrowKind::Unique` are now rejected for internal references.
Mara Bos [Wed, 30 Dec 2020 20:56:51 +0000 (20:56 +0000)]
Rollup merge of #80424 - jyn514:bootstrap-cleanup, r=Mark-Simulacrum
Don't give an error when creating a file for the first time
Previously, `os.remove` would always give a FileNotFound error the first
time you called it, causing bootstrap to make unnecessary copies. This
now only calls `remove()` if the file exists, avoiding the unnecessary
error.
This is a pretty small cleanup but I think it's useful. Taken from https://github.com/rust-lang/rust/pull/79540.
bors [Wed, 30 Dec 2020 15:30:56 +0000 (15:30 +0000)]
Auto merge of #80510 - JohnTitor:rollup-gow7y0l, r=JohnTitor
Rollup of 7 pull requests
Successful merges:
- #80185 (Fix ICE when pointing at multi bytes character)
- #80260 (slightly more typed interface to panic implementation)
- #80311 (Improvements to NatVis support)
- #80337 (Use `desc` as a doc-comment for queries if there are no doc comments)
- #80381 (Revert "Cleanup markdown span handling")
- #80492 (remove empty wraps, don't return Results from from infallible functions)
- #80509 (where possible, pass slices instead of &Vec or &String (clippy::ptr_arg))
Yuki Okushi [Wed, 30 Dec 2020 13:49:24 +0000 (22:49 +0900)]
Rollup merge of #80492 - matthiaskrgr:tasty_wraps, r=varkor
remove empty wraps, don't return Results from from infallible functions
This makes code easier to understand because it is more obvious when a function actually can't fail (return Err or None)
Make functions that only ever return Some(x), return x directly
Remove return type from functions that return Option<(), Err> but would only ever return Ok(()).
Yuki Okushi [Wed, 30 Dec 2020 13:49:23 +0000 (22:49 +0900)]
Rollup merge of #80381 - rust-lang:revert-80244-spans, r=GuillaumeGomez
Revert "Cleanup markdown span handling"
Reverts rust-lang/rust#80244. This caused a diagnostic regression, originally it was:
```
warning: unresolved link to `std::process::Comman`
--> link.rs:3:10
|
3 | //! [a]: std::process::Comman
| ^^^^^^^^^^^^^^^^^^^^ no item named `Comman` in module `process`
|
= note: `#[warn(broken_intra_doc_links)]` on by default
```
but after that PR rustdoc now displays
```
warning: unresolved link to `std::process::Comman`
--> link.rs:1:14
|
1 | //! Links to [a] [link][a]
| ^^^ no item named `Comman` in module `process`
|
= note: `#[warn(broken_intra_doc_links)]` on by default
```
which IMO is much less clear.
cc `@bugadani,` thanks for catching this in https://github.com/rust-lang/rust/pull/77859.
r? `@GuillaumeGomez`
I want to turn `{}` into either `_` or the stringified expr, but [I'm not sure how to do that](https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/Evaluate.20format.20string.20in.20proc-macro). In the meantime, this is better than having no docs at all.
Yuki Okushi [Wed, 30 Dec 2020 13:49:19 +0000 (22:49 +0900)]
Rollup merge of #80311 - sivadeilra:natvis, r=petrochenkov
Improvements to NatVis support
NatVis files describe how to display types in some Windows debuggers,
such as Visual Studio, WinDbg, and VS Code.
This commit makes several improvements:
* Adds visualizers for Rc<T>, Weak<T>, and Arc<T>.
* Changes [size] to [len], for consistency with the Rust API.
Visualizers often use [size] to mirror the size() method on C++ STL
collections.
* Several visualizers used the PVOID and ULONG typedefs. These are part
of the Windows API; they are not guaranteed to always be defined in a
pure Rust DLL/EXE. I converted PVOID to `void*` and `ULONG` to
`unsigned long`.
* Cosmetic change: Removed {} braces around the visualized display
for `Option` types. They now display simply as `Some(value)` or
`None`, which reflects what is written in source code.
* The visualizer for `alloc::string::String` makes assumptions about
the layout of `String` (it casts `String*` to another type), rather
than using symbolic expressions. This commit changes the visualizer
so that it simply uses symbolic expressions to access the string
data and string length.
* The visualizers for `str` and `String` now place the character data
array under a synthetic `[chars]` node. When expanding a `String`
node, users rarely want to see an array of characters. This just places
them behind one expansion node / level.
Yuki Okushi [Wed, 30 Dec 2020 13:49:17 +0000 (22:49 +0900)]
Rollup merge of #80260 - RalfJung:less-untyped-panics, r=m-ou-se
slightly more typed interface to panic implementation
The panic payload is currently being passed around as a `usize`. However, it actually is a pointer, and the involved types are available on all ends of this API, so I propose we use the proper pointer type to avoid some casts. Avoiding int-to-ptr casts also makes this code work with `miri -Zmiri-track-raw-pointers`.
Matthias Krüger [Tue, 29 Dec 2020 21:24:15 +0000 (22:24 +0100)]
remove unused return types such as empty Results or Options that would always be Some(..)
remove unused return type of dropck::check_drop_obligations()
don't wrap return type in Option in get_macro_by_def_id() since we would always return Some(..)
remove redundant return type of back::write::optimize()
don't Option-wrap return type of compute_type_parameters() since we always return Some(..)
don't return empty Result in assemble_generator_candidates()
don't return empty Result in assemble_closure_candidates()
don't return empty result in assemble_fn_pointer_candidates()
don't return empty result in assemble_candidates_from_impls()
don't return empty result in assemble_candidates_from_auto_impls()
don't return emtpy result in assemble_candidates_for_trait_alias()
don't return empty result in assemble_builtin_bound_candidates()
don't return empty results in assemble_extension_candidates_for_traits_in_scope() and assemble_extension_candidates_for_trait()
remove redundant wrapping of return type of StripItem::strip() since it always returns Some(..)
remove unused return type of assemble_extension_candidates_for_all_traits()
Yuki Okushi [Wed, 30 Dec 2020 09:15:23 +0000 (18:15 +0900)]
Rollup merge of #80472 - GuillaumeGomez:sans-serif-for-all-items-page, r=Nemo157
Use sans-serif font for the "all items" page links
The "all items" pages' links aren't using a sans-serif font unlike the rest of equivalent items in the other module pages. ``@Nemo157`` reported me this issue so here is the fix!
Yuki Okushi [Wed, 30 Dec 2020 09:15:21 +0000 (18:15 +0900)]
Rollup merge of #80469 - BlackHoleFox:fix-time-typo, r=jonas-schievink
Fix small typo in time comment
I was reading through [this PR](https://github.com/rust-lang/rust/pull/77727/files) and noticed a [small typo](https://github.com/rust-lang/rust/pull/77727/files#diff-3183738c82f747fd92bb573712073aa384b16e14d154bf2df18f41077edc31cbR240) smuggled though. This just fixes that.
Yuki Okushi [Wed, 30 Dec 2020 09:15:14 +0000 (18:15 +0900)]
Rollup merge of #80461 - rust-lang:tmandry-patch-1, r=Mark-Simulacrum
Add llvm-libunwind change to bootstrap CHANGELOG
From #77703.
This doesn't need a `changelog-seen` version bump because the old values aren't accepted anymore, meaning anyone who was using this had to change it already.
Yuki Okushi [Wed, 30 Dec 2020 09:15:11 +0000 (18:15 +0900)]
Rollup merge of #80358 - pierwill:edit_rustc_span, r=lcnr
Edit rustc_span documentation
Various changes to the `rustc_span` docs, including the following:
- Additions to top-level docs
- Edits to the source_map module docs
- Edits to documentation for `Span` and `SpanData`
- Added intra-docs links
- Documentation for Levenshtein distances
- Fixed missing punctuation
bors [Wed, 30 Dec 2020 07:04:49 +0000 (07:04 +0000)]
Auto merge of #79472 - Aaron1011:new-remove-pretty-print-hack, r=petrochenkov
Replace pretty-print/compare/retokenize hack with targeted workarounds
Based on https://github.com/rust-lang/rust/pull/78296
cc https://github.com/rust-lang/rust/issues/43081
The 'pretty-print/compare/retokenize' hack is used to try to avoid passing an outdated `TokenStream` to a proc-macro when the underlying AST is modified in some way (e.g. cfg-stripping before derives). Unfortunately, retokenizing throws away spans (including hygiene information), which causes issues of its own. Every improvement to the accuracy of the pretty-print/retokenize comparison has resulted in non-trivial ecosystem breakage due to hygiene changes. In extreme cases, users deliberately wrote unhygienic `macro_rules!` macros (likely because they did not realize that the compiler's behavior was a bug).
Additionaly, the comparison between the original and pretty-printed/retoknized token streams comes at a non-trivial runtime cost, as shown by https://github.com/rust-lang/rust/pull/79338
This PR removes the pretty-print/compare/retokenize logic from `nt_to_tokenstream`. We only discard the original `TokenStream` under two circumstances:
* Inner attributes are used (detected by examining the AST)
* `cfg`/`cfg_attr` processing modifies the AST. This is detected by making the visitor update a flag when it performs a modification, instead of trying to detect the modification after-the-fact. Note that a 'matching' `cfg` (e.g. `#[cfg(not(FALSE)]`) does not actually get removed from the AST, allowing us to preserve the original `TokenStream`.
In all other cases, we preserve the original `TokenStream`.
This could use a bit of refactoring/renaming - opening for a Crater run.
bors [Tue, 29 Dec 2020 23:20:46 +0000 (23:20 +0000)]
Auto merge of #80453 - petrochenkov:nocfail, r=Mark-Simulacrum
Remove `compile-fail` test suite
By moving all of its tests to `ui` test suite.
Now we have directives like `// dont-check-compiler-stderr` that allow to disable `.stderr` comparison for platform-dependent tests without introducing a whole new test suite.
bors [Tue, 29 Dec 2020 00:16:54 +0000 (00:16 +0000)]
Auto merge of #80449 - m-ou-se:rollup-kp2e5n8, r=m-ou-se
Rollup of 11 pull requests
Successful merges:
- #80383 (clarify wrapping ptr arithmetic docs)
- #80390 (BTreeMap: rename the area access methods)
- #80393 (Add links to the source for the rustc and rustdoc books.)
- #80398 (Use raw version of align_of in rc data_offset)
- #80402 (Document `InferTy` & co.)
- #80403 (fix: small typo error in chalk/mod.rs)
- #80410 (rustdoc book: fix example)
- #80419 (Add regression test for #80375)
- #80430 (Add "length" as doc alias to len methods)
- #80431 (Add "chr" as doc alias to char::from_u32)
- #80448 (Fix stabilization version of deque_range feature.)
Arlie Davis [Tue, 22 Dec 2020 22:02:07 +0000 (14:02 -0800)]
Improvements to NatVis support
NatVis files describe how to display types in some Windows debuggers,
such as Visual Studio, WinDbg, and VS Code.
This commit makes several improvements:
* Adds visualizers for Rc<T>, Weak<T>, and Arc<T>.
* Changes [size] to [len], for consistency with the Rust API.
Visualizers often use [size] to mirror the size() method on C++ STL
collections.
* Several visualizers used the PVOID and ULONG typedefs. These are part
of the Windows API; they are not guaranteed to always be defined in a
pure Rust DLL/EXE. I converted PVOID to `void*` and `ULONG` to
`unsigned long`.
* Cosmetic change: Removed {} braces around the visualized display
for `Option` types. They now display simply as `Some(value)` or
`None`, which reflects what is written in source code.
* The visualizer for `alloc::string::String` makes assumptions about
the layout of `String` (it casts `String*` to another type), rather
than using symbolic expressions. This commit changes the visualizer
so that it simply uses symbolic expressions to access the string
data and string length.
Mara Bos [Mon, 28 Dec 2020 19:09:34 +0000 (19:09 +0000)]
Rollup merge of #80431 - xfix:add-chr-as-doc-alias, r=steveklabnik
Add "chr" as doc alias to char::from_u32
Many programming languages provide a function called `chr` - Perl, Python, PHP, Visual Basic, SQL. This change makes `char::from_u32` easier to discover in the documentation.
`ord` is not added as its name conflicts with `Ord` trait, and it's not exactly clear what it could point to (`<u32 as From<char>>::from`?). I don't think it's exactly necessary, as `char::from_u32` documentation page says you can do reverse conversion with `as` operator anyway.
Mara Bos [Mon, 28 Dec 2020 19:09:32 +0000 (19:09 +0000)]
Rollup merge of #80430 - xfix:add-length-as-doc-alias, r=steveklabnik
Add "length" as doc alias to len methods
Currently when searching for `length` there are no results: https://doc.rust-lang.org/std/?search=length. This makes `len` methods appear when searching for `length`.
Mara Bos [Mon, 28 Dec 2020 19:09:25 +0000 (19:09 +0000)]
Rollup merge of #80402 - camelid:inferty-docs, r=matthewjasper
Document `InferTy` & co.
I finally figured out what `TyVid` means! The name is quite opaque, so I
decided to document it and related types.
I don't know that much about `InferTy` & co., but I was able to *infer*
( :) ) from the names and what I know generally about type inference to
add some basic documentation.
Mara Bos [Mon, 28 Dec 2020 19:09:22 +0000 (19:09 +0000)]
Rollup merge of #80393 - ehuss:doc-git-link, r=jyn514
Add links to the source for the rustc and rustdoc books.
This adds a little icon in the upper-right corner of the books so that readers can find the source if they want to make changes or file issues. This is already included in several of the other books.