13 commits in b278478b766178491a8b6f67afa4bcd6b64d977a..50af691f838937c300b47812d0507c6d88c14f97
2020-12-21 18:18:03 -0800 to 2021-01-12 21:19:20 -0800
- Update grammar for parser unification. (rust-lang/reference#927)
- Define constraining an implementation (rust-lang/reference#928)
- Document extra behavior of #[no_mangle] (rust-lang/reference#930)
- Add a float examle without a `.`. (rust-lang/reference#929)
- Add more details about const generics. (rust-lang/reference#921)
- Fix footnotes. (rust-lang/reference#926)
- Add "Logic errors" as behavior not considered unsafe (rust-lang/reference#919)
- Update grammar for order of parameters/arguments. (rust-lang/reference#920)
- Fix formatting in the tuple section (rust-lang/reference#923)
- document const generics (rust-lang/reference#901)
- Update mdbook (rust-lang/reference#918)
- linkage.md: update link to FFI section of the Book. (rust-lang/reference#917)
- Document array expression with a const. (rust-lang/reference#914)
## book
8 commits in 5bb44f8b5b0aa105c8b22602e9b18800484afa21..ac57a0ddd23d173b26731ccf939f3ba729753275
2020-12-18 20:07:31 -0500 to 2021-01-09 14:18:45 -0500
- Update version of mdbook we're testing with to 0.4.5 (rust-lang/book#2561)
- Fix grammar in ch13-01-closures.md (rust-lang/book#2534)
- Merge remote-tracking branch 'origin/pr/2527'
- Clarify code example ch6.3 (rust-lang/book#2485)
- Fix link added in rust-lang/book#2495 to be relative and at the bottom
- Merge remote-tracking branch 'origin/pr/2495'
- Update output to match the updated poem punctuation
- Fix rust-lang/book#2539 - Remove fancy apostrophes from poem for Windows
## rust-by-example
3 commits in 1cce0737d6a7d3ceafb139b4a206861fb1dcb2ab..03e23af01f0b4f83a3a513da280e1ca92587f2ec
2020-12-21 17:36:29 -0300 to 2021-01-09 10:20:28 -0300
- Replace for loop with iteration (rust-lang/rust-by-example#1404)
- Update mdbook (rust-lang/rust-by-example#1402)
- Add note for match guards to include catch-all (rust-lang/rust-by-example#1401)
Mara Bos [Thu, 14 Jan 2021 18:00:14 +0000 (18:00 +0000)]
Rollup merge of #80966 - KodrAus:deprecate/spin_loop_hint, r=m-ou-se
Deprecate atomic::spin_loop_hint in favour of hint::spin_loop
For https://github.com/rust-lang/rust/issues/55002
We wanted to leave `atomic::spin_loop_hint` alone when stabilizing `hint::spin_loop` so folks had some time to migrate. This now deprecates `atomic_spin_loop_hint`.
Mara Bos [Thu, 14 Jan 2021 18:00:11 +0000 (18:00 +0000)]
Rollup merge of #80895 - sfackler:read-to-end-ub, r=m-ou-se
Fix handling of malicious Readers in read_to_end
A malicious `Read` impl could return overly large values from `read`, which would result in the guard's drop impl setting the buffer's length to greater than its capacity! ~~To fix this, the drop impl now uses the safe `truncate` function instead of `set_len` which ensures that this will not happen. The result of calling the function will be nonsensical, but that's fine given the contract violation of the `Read` impl.~~
~~The `Guard` type is also used by `append_to_string` which does not pass untrusted values into the length field, so I've copied the guard type into each function and only modified the one used by `read_to_end`. We could just keep a single one and modify it, but it seems a bit cleaner to keep the guard code close to the functions and related specifically to them.~~
To fix this, we now assert that the returned length is not larger than the buffer passed to the method.
Mara Bos [Thu, 14 Jan 2021 18:00:06 +0000 (18:00 +0000)]
Rollup merge of #80567 - lukaslueg:intersperse_with, r=m-ou-se
Add Iterator::intersperse_with
This is a follow-up to #79479, tracking in #79524, as discussed https://github.com/rust-lang/rust/pull/79479#issuecomment-752671731.
~~Note that I had to manually implement `Clone` and `Debug` because `derive` insists on placing a `Clone`-bound on the struct-definition, which is too narrow. There is a long-standing issue # for this somewhere around here :-)~~
Also, note that I refactored the guts of `Intersperse` into private functions and re-used them in `IntersperseWith`, so I also went light on duplicating all the tests.
If this is suitable to be merged, the tracking issue should be updated, since it only mentions `intersperse`.
Mara Bos [Thu, 14 Jan 2021 18:00:02 +0000 (18:00 +0000)]
Rollup merge of #80444 - glittershark:bound-as-ref, r=dtolnay
Add as_ref and as_mut methods for Bound
Add as_ref and as_mut method for std::ops::range::Bound, patterned off
of the methods of the same name on Option.
I'm not quite sure what the process is for introducing new feature gates (this is my first contribution) so I've left these ungated, but happy to do whatever is necessary to gate them.
Mara Bos [Thu, 14 Jan 2021 18:00:00 +0000 (18:00 +0000)]
Rollup merge of #80217 - camelid:io-read_to_string, r=m-ou-se
Add a `std::io::read_to_string` function
I recognize that you're usually supposed to open an issue first, but the
implementation is very small so it's okay if this is closed and it was 'wasted
work' :)
-----
The equivalent of `std::fs::read_to_string`, but generalized to all
`Read` impls.
As the documentation on `std::io::read_to_string` says, the advantage of
this function is that it means you don't have to create a variable first
and it provides more type safety since you can only get the buffer out
if there were no errors. If you use `Read::read_to_string`, you have to
remember to check whether the read succeeded because otherwise your
buffer will be empty.
It's friendlier to newcomers and better in most cases to use an explicit
return value instead of an out parameter.
Mara Bos [Thu, 14 Jan 2021 17:59:53 +0000 (17:59 +0000)]
Rollup merge of #79982 - ijackson:exit-status, r=dtolnay
Add missing methods to unix ExitStatusExt
These are the methods corresponding to the remaining exit status examination macros from `wait.h`. `WCOREDUMP` isn't in SuS but is it is very standard. I have not done portability testing to see if this builds everywhere, so I may need to Do Something if it doesn't.
There is also a bugfix and doc improvement to `.signal()`, and an `.into_raw()` accessor.
This would fix #73128 and fix #73129. Please let me know if you like this direction, and if so I will open the tracking issue and so on.
If this MR goes well, I may tackle #73125 next - I have an idea for how to do it.
bors [Thu, 14 Jan 2021 14:41:58 +0000 (14:41 +0000)]
Auto merge of #79328 - c410-f3r:hir-if, r=matthewjasper
Reintroduce hir::ExprKind::If
Basically copied and paste #59288/https://github.com/rust-lang/rust-clippy/pull/4080 with some modifications.
The vast majority of tests were fixed and now there are only a few remaining. Since I am still unable to figure out the missing pieces, any help with the following list is welcome.
bors [Thu, 14 Jan 2021 08:46:55 +0000 (08:46 +0000)]
Auto merge of #78259 - plaflamme:fix-49660, r=KodrAus
Fix #49660 - Adds checks to ensure existence of arithmetic trait implementations
The first 2 commits fix an issue with the existing `wrapping.rs` tests. It wasn't referred to from the module, so the file was being ignored. This is fixed in https://github.com/rust-lang/rust/pull/78259/commits/872dc60ed203d16d43140c1d1623474cf8a9aedc This surfaced a bug in its macro which is fixed in https://github.com/rust-lang/rust/pull/78259/commits/8ddad18283e304753e09ef651209b4a6b54148b0
* `Add`, `Sub`, `Mul`, `Div`, `Rem`
* `T op T`, `T op &T`, `&T op T` and `&T op &T`
* for all integer and floating point types
* `AddAssign`, `SubAssign`, `MulAssign`, `DivAssign`, `RemAssign`
* `&mut T op T` and `&mut T op &T`
* for all integer and floating point types
* `Neg`
* `op T` and `op &T`
* for all signed integer and floating point types
* `Not`
* `op T` and `op &T`
* for `bool`
* `BitAnd`, `BitOr`, `BitXor`
* `T op T`, `T op &T`, `&T op T` and `&T op &T`
* for all integer types and bool
* `BitAndAssign`, `BitOrAssign`, `BitXorAssign`
* `&mut T op T` and `&mut T op &T`
* for all integer types and bool
* `Shl`, `Shr`
* `L op R`, `L op &R`, `&L op R` and `&L op &R`
* for all pairs of integer types
* `ShlAssign`, `ShrAssign`
* `&mut L op R`, `&mut L op &R`
* for all pairs of integer types
NOTE: I'd like some feedback on improving the macros. I'm not familiar with the idioms and patterns there and composing them has been a challenge for me.
These tests invoke the various op traits using all accepted types they
are implemented for as well as for references to those types.
This fixes #49660 and ensures the following implementations exist:
* `Add`, `Sub`, `Mul`, `Div`, `Rem`
* `T op T`, `T op &T`, `&T op T` and `&T op &T`
* for all integer and floating point types
* `AddAssign`, `SubAssign`, `MulAssign`, `DivAssign`, `RemAssign`
* `&mut T op T` and `&mut T op &T`
* for all integer and floating point types
* `Neg`
* `op T` and `op &T`
* for all signed integer and floating point types
* `Not`
* `op T` and `op &T`
* for `bool`
* `BitAnd`, `BitOr`, `BitXor`
* `T op T`, `T op &T`, `&T op T` and `&T op &T`
* for all integer types and bool
* `BitAndAssign`, `BitOrAssign`, `BitXorAssign`
* `&mut T op T` and `&mut T op &T`
* for all integer types and bool
* `Shl`, `Shr`
* `L op R`, `L op &R`, `&L op R` and `&L op &R`
* for all pairs of integer types
* `ShlAssign`, `ShrAssign`
* `&mut L op R`, `&mut L op &R`
* for all pairs of integer types
bors [Wed, 13 Jan 2021 23:24:31 +0000 (23:24 +0000)]
Auto merge of #80654 - Aaron1011:fix/dummy-span-ctxt, r=wesleywiser
Properly handle `SyntaxContext` of dummy spans in incr comp
Fixes #80336
Due to macro expansion, we may end up with spans with an invalid
location and non-root `SyntaxContext`. This commits preserves the
`SyntaxContext` of such spans in the incremental cache, and ensures
that we always hash the `SyntaxContext` when computing the `Fingerprint`
of a `Span`
Previously, we would discard the `SyntaxContext` during serialization to
the incremental cache, causing the span's `Fingerprint` to change across
compilation sessions.
Aaron Hill [Sun, 3 Jan 2021 15:09:32 +0000 (10:09 -0500)]
Properly handle `SyntaxContext` of dummy spans in incr comp
Fixes #80336
Due to macro expansion, we may end up with spans with an invalid
location and non-root `SyntaxContext`. This commits preserves the
`SyntaxContext` of such spans in the incremental cache, and ensures
that we always hash the `SyntaxContext` when computing the `Fingerprint`
of a `Span`
Previously, we would discard the `SyntaxContext` during serialization to
the incremental cache, causing the span's `Fingerprint` to change across
compilation sessions.
bors [Wed, 13 Jan 2021 17:48:41 +0000 (17:48 +0000)]
Auto merge of #80718 - tmiasko:skip-opt-mir, r=oli-obk
Consistently avoid constructing optimized MIR when not doing codegen
The optimized MIR for closures is being encoded unconditionally, while
being unnecessary for cargo check. This turns out to be especially
costly with MIR inlining enabled, since it triggers computation of
optimized MIR for all callees that are being examined for inlining
purposes https://github.com/rust-lang/rust/pull/77307#issuecomment-751915450.
Skip encoding of optimized MIR for closures, enum constructors, struct
constructors, and trait fns when not doing codegen, like it is already
done for other items since 49433.
bors [Wed, 13 Jan 2021 13:56:15 +0000 (13:56 +0000)]
Auto merge of #76219 - Mark-Simulacrum:extern-require-abi, r=estebank
Add allow-by-default lint on implicit ABI in extern function pointers and items
This adds a new lint, missing_abi, which lints on omitted ABIs on extern blocks, function declarations, and function pointers.
It is currently not emitting the best possible diagnostics -- we need to track the span of "extern" at least or do some heuristic searching based on the available spans -- but seems good enough for an initial pass than can be expanded in future PRs.
This is a pretty large PR, but mostly due to updating a large number of tests to include ABIs; I can split that into a separate PR if it would be helpful, but test updates are already in dedicated commits.
Ian Jackson [Mon, 4 Jan 2021 17:11:41 +0000 (17:11 +0000)]
ExitStatusExt unix: Retrospectively seal this trait
As discussed in #79982.
I think the "new interfaces", ie the new trait and impl, must be
insta-stable. This seems OK because we are, in fact, adding a new
restriction to the stable API.
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
It will not be easy to experience this bug with `Command`, because
that doesn't pass WUNTRACED. But you could make an ExitStatus
containing, say, a WIFSTOPPED, from a call to one of the libc wait
functions.
(In the WIFSTOPPED case, there is WSTOPSIG. But a stop signal is
encoded differently to a termination signal, so WTERMSIG and WSTOPSIG
are by no means the same.)
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
bors [Wed, 13 Jan 2021 11:11:34 +0000 (11:11 +0000)]
Auto merge of #80824 - cuviper:heap-clones, r=kennytm
Try to avoid locals when cloning into Box/Rc/Arc
For generic `T: Clone`, we can allocate an uninitialized box beforehand,
which gives the optimizer a chance to create the clone directly in the
heap. For `T: Copy`, we can go further and do a simple memory copy,
regardless of optimization level.
The same applies to `Rc`/`Arc::make_mut` when they must clone the data.
The proliferation of `split_*` methods is not particularly pretty. The existence of `split_inclusive` seems to invite the addition of `rsplit_inclusive`, `splitn_inclusive`, etc. We could instead have a more general API, along these kinds of lines maybe:
```
pub fn split_generic('a,P,H>(&'a self, pat: P, how: H) -> ...
where P: Pattern
where H: SplitHow;
pub fn split_generic_mut('a,P,H>(&'a mut self, pat: P, how: H) -> ...
where P: Pattern
where H: SplitHow;
pub struct SplitFwd;
...
pub struct SplitRevInclN(pub usize);
```
But maybe that is worse.
### Let us defer that? ###
This seems like a can of worms. I think we can defer opening it now; if and when we have something more general, these two methods can become convenience aliases. But I thought I would mention it so the lang API team can consider it and have an opinion.
Dylan DPC [Wed, 13 Jan 2021 02:20:27 +0000 (03:20 +0100)]
Rollup merge of #80935 - pierwill:rustc_middle-levelandsource, r=petrochenkov
Rename `rustc_middle::lint::LevelSource` to `LevelAndSource`
This continues work in https://github.com/rust-lang/rust/pull/80274 to improve code readability.
This naming follows a pattern seen elsewhere in the compiler (e.g. [`rustc_middle::ty::TypeAndMut`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.TypeAndMut.html)).
Dylan DPC [Wed, 13 Jan 2021 02:20:21 +0000 (03:20 +0100)]
Rollup merge of #80859 - jsgf:fix-pretty-remap, r=davidtwco
Fix --pretty=expanded with --remap-path-prefix
Per https://github.com/rust-lang/rust/issues/80832, using
--pretty=expanded and --remap-path-prefix results in an ICE.
This is becasue the session source files table is stored in remapped
form, whereas --pretty-expanded looks up unremapped files. This remaps
the path prefixes before lookup.
~~There don't appear to be any existing tests for --pretty=expanded; I'll look into
adding some.~~ Never mind, found the pretty tests.
Dylan DPC [Wed, 13 Jan 2021 02:20:19 +0000 (03:20 +0100)]
Rollup merge of #80796 - cuviper:llvm-11.0.1, r=nikic
Update to LLVM 11.0.1
This updates to a new LLVM branch, rebased on the upstream `llvmorg-11.0.1`. All our patches applied cleanly except the fortanix unwind changes, which just needed a small adjustment in cmake files.
Dylan DPC [Wed, 13 Jan 2021 02:20:17 +0000 (03:20 +0100)]
Rollup merge of #80736 - KodrAus:feat/lazy-resolve, r=dtolnay
use Once instead of Mutex to manage capture resolution
For #78299
This allows us to return borrows of the captured backtrace frames that are tied to a borrow of the Backtrace itself, instead of to some short-lived Mutex guard.
We could alternatively share `&Mutex<Capture>`s and lock on-demand, but then we could potentially forget to call `resolve()` before working with the capture. It also makes it semantically clearer what synchronization is needed on the capture.
cc `@seanchen1991` `@rust-lang/project-error-handling`
bors [Wed, 13 Jan 2021 01:40:41 +0000 (01:40 +0000)]
Auto merge of #79322 - jyn514:refactor-impl, r=estebank
Separate out a `hir::Impl` struct
This makes it possible to pass the `Impl` directly to functions, instead
of having to pass each of the many fields one at a time. It also
simplifies matches in many cases.
See `rustc_save_analysis::dump_visitor::process_impl` or `rustdoc::clean::clean_impl` for a good example of how this makes `impl`s easier to work with.
Joshua Nelson [Sun, 22 Nov 2020 22:46:21 +0000 (17:46 -0500)]
Separate out a `hir::Impl` struct
This makes it possible to pass the `Impl` directly to functions, instead
of having to pass each of the many fields one at a time. It also
simplifies matches in many cases.
Tomasz Miąsko [Tue, 12 Jan 2021 00:00:00 +0000 (00:00 +0000)]
Consistently avoid constructing optimized MIR when not doing codegen
The optimized MIR for closures is being encoded unconditionally, while
being unnecessary for cargo check. This turns out to be especially
costly with MIR inlining enabled, since it triggers computation of
optimized MIR for all callees that are being examined for inlining
purposes.
Skip encoding of optimized MIR for closures, enum constructors, struct
constructors, and trait fns when not doing codegen, like it is already
done for other items since 49433.
bors [Tue, 12 Jan 2021 22:58:42 +0000 (22:58 +0000)]
Auto merge of #79670 - Nadrieril:uninhabited-query, r=estebank
Turn type inhabitedness into a query to fix `exhaustive_patterns` perf
We measured in https://github.com/rust-lang/rust/pull/79394 that enabling the [`exhaustive_patterns` feature](https://github.com/rust-lang/rust/issues/51085) causes significant perf degradation. It was conjectured that the culprit is type inhabitedness checking, and [I hypothesized](https://github.com/rust-lang/rust/pull/79394#issuecomment-733861149) that turning this computation into a query would solve most of the problem.
This PR turns `tcx.is_ty_uninhabited_from` into a query, and I measured a 25% perf gain on the benchmark that stress-tests `exhaustiveness_patterns`. This more than compensates for the 30% perf hit I measured [when creating it](https://github.com/rust-lang/rustc-perf/pull/801). We'll have to measure enabling the feature again, but I suspect this fixes the perf regression entirely.
I'd like a perf run on this PR obviously.
I made small atomic commits to help reviewing. The first one is just me discovering the "revisions" feature of the testing framework.
I believe there's a push to move things out of `rustc_middle` because it's huge. I guess `inhabitedness/mod.rs` could be moved out, but it's quite small. `DefIdForest` might be movable somewhere too. I don't know what the policy is for that.
Ping `@camelid` since you were interested in following along
`@rustbot` modify labels: +A-exhaustiveness-checking
Nadrieril [Thu, 3 Dec 2020 01:52:24 +0000 (01:52 +0000)]
Make `DefIdForest` cheaper to clone
Since `DefIdForest` contains 0 or 1 elements the large majority of the
time, by allocating only in the >1 case we avoid almost all allocations,
compared to `Arc<SmallVec<[DefId;1]>>`. This shaves off 0.2% on the
benchmark that stresses uninhabitedness checking.
bors [Tue, 12 Jan 2021 17:26:56 +0000 (17:26 +0000)]
Auto merge of #78407 - oli-obk:ub_checkable_ctfe, r=RalfJung,pnkfelix
Make CTFE able to check for UB...
... by not doing any optimizations on the `const fn` MIR used in CTFE. This means we duplicate all `const fn`'s MIR now, once for CTFE, once for runtime. This PR is for checking the perf effect, so we have some data when talking about https://github.com/rust-lang/const-eval/blob/master/rfcs/0000-const-ub.md
To do this, we now have two queries for obtaining mir: `optimized_mir` and `mir_for_ctfe`. It is now illegal to invoke `optimized_mir` to obtain the MIR of a const/static item's initializer, an array length, an inline const expression or an enum discriminant initializer. For `const fn`, both `optimized_mir` and `mir_for_ctfe` work, the former returning the MIR that LLVM should use if the function is called at runtime. Similarly it is illegal to invoke `mir_for_ctfe` on regular functions.
This is all checked via appropriate assertions and I don't think it is easy to get wrong, as there should be no `mir_for_ctfe` calls outside the const evaluator or metadata encoding. Almost all rustc devs should keep using `optimized_mir` (or `instance_mir` for that matter).