Rollup merge of #66017 - LukasKalbertodt:array-into-iter-lint, r=matthewjasper
Add future incompatibility lint for `array.into_iter()`
This is for #65819. This lint warns when calling `into_iter` on an array directly. That's because today the method call resolves to `<&[T] as IntoIterator>::into_iter` but that would change when adding `IntoIterator` impls for arrays. This problem is discussed in detail in #65819.
We still haven't decided how to proceed exactly, but it seems like adding a lint is a good idea regardless?
Also: this is the first time I implement a lint, so there are probably a lot of things I can improve. I used a different strategy than @scottmcm describes [here](https://github.com/rust-lang/rust/pull/65819#issuecomment-548667847) since I already started implementing this before they commented.
### TODO
- [x] Decide if we want this lint -> apparently [we want](https://github.com/rust-lang/rust/pull/65819#issuecomment-548964818)
- [x] Open a lint-tracking-issue and add the correct issue number in the code -> https://github.com/rust-lang/rust/issues/66145
Rollup merge of #65974 - Centril:matcher-friendly-gating, r=petrochenkov
A scheme for more macro-matcher friendly pre-expansion gating
Pre-expansion gating will now avoid gating macro matchers that did not result in `Success(...)`. That is, the following is now OK despite `box 42` being a valid `expr` and that form being pre-expansion gated:
```rust
macro_rules! m {
($e:expr) => { 0 }; // This fails on the input below due to `, foo`.
(box $e:expr, foo) => { 1 }; // Successful matcher, we should get `2`.
}
Rollup merge of #65884 - Centril:non-hardcoded-abis, r=petrochenkov
syntax: ABI-oblivious grammar
This PR has the following effects:
1. `extern $lit` is now legal where `$lit:literal` and `$lit` is substituted for a string literal.
2. `extern "abi_that_does_not_exist"` is now *syntactically* legal whereas before, the set of ABI strings was hard-coded into the grammar of the language. With this PR, the set of ABIs are instead validated and translated during lowering. That seems more appropriate.
3. `ast::FloatTy` is now distinct from `rustc_target::abi::FloatTy`. The former is used substantially more and the translation between them is only necessary in a single place.
4. As a result of 2-3, libsyntax no longer depends on librustc_target, which should improve pipe-lining somewhat.
cc @rust-lang/lang -- the points 1-2 slightly change the definition of the language but in a way which seems consistent with our general principles (in particular wrt. the discussions of turning things into semantic errors). I expect this to be uncontroversial but it's worth letting y'all know. :)
Use structured suggestions for missing associated items
When encountering an `impl` that is missing associated items required by its `trait`, use structured suggestions at an appropriate place in the `impl`.
Rollup merge of #59789 - eddyb:typeck-reverts, r=nikomatsakis
Revert two unapproved changes to rustc_typeck.
There was a breakdown in process (https://github.com/rust-lang/rust/pull/59004#issuecomment-477600735, https://github.com/rust-lang/rust/pull/58894#discussion_r272795560) and two changes were made to `rustc_typeck`'s "collect" queries, for rustdoc, that were neither needed *nor* correct.
I'm reverting them here, and will fix up rustdoc *somehow*, if necessary.
cc @rust-lang/compiler How do we ensure this doesn't happen again?
Yuki Okushi [Thu, 7 Nov 2019 00:20:48 +0000 (09:20 +0900)]
Rollup merge of #66162 - Darksonn:master, r=ehuss
Fix broken link in README
The link to the rustc guide on building and running the compiler is broken. It was broken in [rustc-guide#491](https://github.com/rust-lang/rustc-guide/pull/491).
Yuki Okushi [Thu, 7 Nov 2019 00:20:46 +0000 (09:20 +0900)]
Rollup merge of #66147 - RalfJung:no-scalar-ptr, r=oli-obk
Miri: Refactor to_scalar_ptr out of existence
`to_scalar_ptr` is somewhat subtle as it just throws away the 2nd component of a `ScalarPair` if there is one -- without any check if this is truly a pointer or so. And indeed we used it wrong on two occasions!
So I fixed those two, and then refactored things such that everyone calls `ref_to_mplace` instead (which they did anyway, I just moved up the calls), which is the only place that should interpret a `ScalarPair` as a wide ptr -- and it checks the type first. Thus we can remove `to_scalar_ptr` and `to_meta`.
Yuki Okushi [Thu, 7 Nov 2019 00:20:44 +0000 (09:20 +0900)]
Rollup merge of #66117 - olegnn:fixed_linked_list_marker, r=RalfJung
Fixed PhantomData markers in Arc and Rc
Include owned internal structs in `PhantomData` markers in `Arc` (`PhantomData<T>` => `PhantomData<ArcInner<T>>`) and `Rc` (`PhantomData<T>` => `PhantomData<RcBox<T>>`).
Yuki Okushi [Thu, 7 Nov 2019 00:20:41 +0000 (09:20 +0900)]
Rollup merge of #66111 - RalfJung:from_raw_parts, r=Centril
improve from_raw_parts docs
Triggered by https://github.com/rust-lang/rfcs/pull/2806. Hopefully this helps clarify that joining slices across allocations is not possible in Rust currently.
Yuki Okushi [Thu, 7 Nov 2019 00:20:39 +0000 (09:20 +0900)]
Rollup merge of #66084 - petrochenkov:x86arm, r=alexcrichton
Do not require extra LLVM backends for `x.py test` to pass
For long time our testing passed with a partially built LLVM
```
[llvm]
targets = "X86;ARM"
```
, a [recent PR](https://github.com/rust-lang/rust/pull/65809) changed that.
Yuki Okushi [Thu, 7 Nov 2019 00:20:36 +0000 (09:20 +0900)]
Rollup merge of #66044 - RalfJung:uninit-lint, r=oli-obk
Improve uninit/zeroed lint
* Also warn when creating a raw pointer with a NULL vtable.
* Also identify `MaybeUninit::uninit().assume_init()` and `MaybeUninit::zeroed().assume_init()` as dangerous.
bors [Thu, 7 Nov 2019 00:10:52 +0000 (00:10 +0000)]
Auto merge of #65750 - nnethercote:cheaper-doc-comments, r=petrochenkov
Cheaper doc comments
This PR implements the idea from #60935: represent doc comments more cheaply, rather than converting them into `#[doc="..."]` attribute form. Unlike #60936 (which is about coalescing doc comments to reduce their number), this approach does not have any backwards compatibility concerns, and it eliminates about 80-90% of the current cost of doc comments (as estimated using the numbers in #60930, which eliminated the cost of doc comments entirely by treating them as normal comments).
bors [Wed, 6 Nov 2019 18:12:57 +0000 (18:12 +0000)]
Auto merge of #65728 - ecstatic-morse:promotion-const-proj, r=eddyb
Fix promotion in a `const` when projections are present
Resolves #65727.
This marks the entire local as "needs promotion" when only a projection of that local appears in a promotable context. This should only affect promotion in a `const` or `static`, not in a `fn` or `const fn`, which is handled in `promote_consts.rs`.
Add future incompatibility lint for `array.into_iter()`
As we might want to add `IntoIterator` impls for arrays in the future,
and since that introduces a breaking change, this lint warns and
suggests using `iter()` instead (which is shorter and more explicit).
`AttrKind` is a new type with two variants, `Normal` and `DocComment`. It's a
big performance win (over 10% in some cases) because `DocComment` lets doc
comments (which are common) be represented very cheaply.
`Attribute` gets some new helper methods to ease the transition:
- `has_name()`: check if the attribute name matches a single `Symbol`; for
`DocComment` variants it succeeds if the symbol is `sym::doc`.
- `is_doc_comment()`: check if it has a `DocComment` kind.
- `{get,unwrap}_normal_item()`: extract the item from a `Normal` variant;
panic otherwise.
bors [Wed, 6 Nov 2019 09:35:27 +0000 (09:35 +0000)]
Auto merge of #65830 - Quantumplation:master, r=davidtwco,estebank
Use ident.span instead of def_span in dead-code pass
Hello! First time contributor! :)
This should fix #58729.
According to @estebank in the duplicate #63064, def_span scans forward on the line until it finds a {,
and if it can't find one, falls back to the span for the whole item. This
was apparently written before the identifier span was explicitly tracked on
each node.
This means that if an unused function signature spans multiple lines, the
entire function (potentially hundreds of lines) gets flagged as dead code.
This could, for example, cause IDEs to add error squiggly's to the whole
function.
By using the span from the ident instead, we narrow the scope of this in
most cases. In a wider sense, it's probably safe to use ident.span
instead of def_span in most locations throughout the whole code base,
but since this is my first contribution, I kept it small.
Some interesting points that came up while I was working on this:
- I reorganized the tests a bit to bring some of the dead code ones all
into the same location
- A few tests were for things unrelated to dead code (like the
path-lookahead for parens), so I added #![allow(dead_code)] and
cleaned up the stderr file to reduce noise in the future
- The same fix doesn't apply to const and static declarations. I tried
adding these cases to the match expression, but that created a much
wider change to tests and error messages, so I left it off until I
could get some code review to validate the approach.
bors [Wed, 6 Nov 2019 06:14:03 +0000 (06:14 +0000)]
Auto merge of #66143 - Centril:rollup-qmzuex0, r=Centril
Rollup of 9 pull requests
Successful merges:
- #65776 (Rename `LocalInternedString` and more)
- #65973 (caller_location: point to macro invocation sites, like file!/line!, and use in core::panic!.)
- #66015 (librustc_lexer: Refactor the module)
- #66062 (Configure LLVM module PIC level)
- #66086 (bump smallvec to 1.0)
- #66092 (Use KERN_ARND syscall for random numbers on NetBSD, same as FreeBSD.)
- #66103 (Add target thumbv7neon-unknown-linux-musleabihf)
- #66133 (Update the bundled `wasi-libc` repository)
- #66139 (use American spelling for `pluralize!`)
Rollup merge of #66133 - alexcrichton:update-wasi-libc, r=Mark-Simulacrum
Update the bundled `wasi-libc` repository
This updates the libc that the `wasm32-wasi` target links against to the
latest revision, mostly just bringing in minor bug fixes and minor wasm
size improvements.
Rollup merge of #66103 - smaeul:patch/thumb-musl, r=nagisa
Add target thumbv7neon-unknown-linux-musleabihf
This is a copy of thumbv7neon-unknown-linux-gnueabihf with musl changes
merged from armv7-unknown-linux-musleabihf. This appears to have been
missed when adding the other ARMv7-A thumb targets.
Use KERN_ARND syscall for random numbers on NetBSD, same as FreeBSD.
This system call is present on all supported NetBSD versions and provides an endless stream of non-blocking random data from the kernel's ChaCha20-based CSPRNG. It doesn't require a file like `/dev/urandom` to be opened.
The system call is documented here (under kern.arandom):
https://netbsd.gw.com/cgi-bin/man-cgi?sysctl+7+NetBSD-7.0
And defined here:
https://nxr.netbsd.org/xref/src/sys/sys/sysctl.h#273
The semantics are the same as FreeBSD so reading 256 bytes per call is fine.
Similar change for getrandom crate: rust-random/getrandom#115
Rollup merge of #66062 - smaeul:patch/pic-level, r=estebank
Configure LLVM module PIC level
As of LLVM 9, this is required for 32-bit PowerPC to properly generate
PLT references. Previously, only BigPIC was supported; now LLVM supports
both BigPIC and SmallPIC, and there is no default value provided.
Rollup merge of #66015 - popzxc:refactor-librustc_parser, r=matklad
librustc_lexer: Refactor the module
This PR introduces a refactoring of the `librustc_lexer` in order to improve readability.
All the changes performed are only cosmetic and do not introduce any changes the lexer logic or performance.
Newly introduced modules `literal`, `token` and `utils` are just copy-pasted from the `lib.rs` and do not contain even cosmetic changes (I decided to do so so it'll be easier to review changes looking only on diff).
Rollup merge of #65973 - eddyb:caller-location-panic, r=petrochenkov
caller_location: point to macro invocation sites, like file!/line!, and use in core::panic!.
The main change here is to `core::panic!`, trying to fix this remaining regression: https://github.com/rust-lang/rust/pull/65927#issuecomment-547625147
However, in order for `caller_location` to be usable from macros the same way `file!()`/`line!()` are, it needs to have the same behavior (of extracting the macro invocation site `Span` and using that).
Arguably we would've had to do this at some point anyway, if we want to use `#[track_caller]` to replace the `file!()`/`line!()` uses from macros, but I'm not sure the RFC mentions this at all.
bors [Wed, 6 Nov 2019 02:29:21 +0000 (02:29 +0000)]
Auto merge of #66141 - Centril:rollup-n2fcvp9, r=Centril
Rollup of 11 pull requests
Successful merges:
- #65892 (Remove `PartialEq` and `Eq` from the `SpecialDerives`.)
- #66014 (Show type parameter name and definition in type mismatch error messages )
- #66027 (Move has_panic_handler to query)
- #66054 (syntax: Avoid span arithmetic for delimiter tokens)
- #66068 (use silent emitter for rustdoc highlighting pass)
- #66081 (let caller of check_ptr_access_align control the error message)
- #66093 (Do not ICE with a precision flag in formatting str and no format arguments)
- #66098 (Detect `::` -> `:` typo when involving turbofish)
- #66101 (Tweak type mismatch caused by break on tail expr)
- #66106 (Fix typo in explanation of `E0080`)
- #66115 (rustc: remove "GlobalMetaData" dead code from hir::map::definitions.)
Rollup merge of #66101 - estebank:break-tail-e0308, r=Centril
Tweak type mismatch caused by break on tail expr
When `break;` has a type mismatch because the `Destination` points at a tail
expression with an obligation flowing from a return type, point at the
return type.
Rollup merge of #66054 - petrochenkov:delspan, r=estebank
syntax: Avoid span arithmetic for delimiter tokens
The +/-1 logic is from the time where the whole group had a single span and the delimiter spans had to be calculated from it.
Now the delimiters have their own spans which are constructed by lexer or proc macro API and can be used directly.
If those spans are not perfect, then it should be fixed by tweaking the corresponding lexer logic rather than by trying to add or substract `1` from the span boundaries.
Rollup merge of #66027 - Mark-Simulacrum:panic-handler-query, r=alexcrichton
Move has_panic_handler to query
Moves us off of a global Once instead re-querying the lang item each time. The conditions on when we set it to true change a little (previously we'd make sure a few more lang items were `Some`) but I think they in practice don't matter, we won't compile later on if we don't have them.
Esteban Küber [Tue, 5 Nov 2019 02:47:02 +0000 (18:47 -0800)]
Tweak type mismatch caused by break on tail expr
When `break;` has a type mismatch because the `Destination` points at a tail
expression with an obligation flowing from a return type, point at the
return type.
Alex Crichton [Tue, 5 Nov 2019 19:49:23 +0000 (11:49 -0800)]
Update the bundled `wasi-libc` repository
This updates the libc that the `wasm32-wasi` target links against to the
latest revision, mostly just bringing in minor bug fixes and minor wasm
size improvements.
Pi Lanningham [Tue, 5 Nov 2019 15:42:34 +0000 (15:42 +0000)]
Detect if item.span is in a macro, and fall back
If item.span is part of a macro invocation, this has several downstream
implications. To name two that were found while working on this:
- The dead-code error gets annotated with a "in this macro invocation"
- Some errors get canceled if they refer to remote crates
Ideally, we should annotate item.ident.span with the same macro info,
but this is a larger change (see: #66095), so for now we just fall
back to the old behavior if this item was generated by a macro.
I use span.macro_backtrace().len() to detect if it's part of a macro,
because that (among other things) is what is used by the code which
adds the "in this macro invocation" annotations mentioned above.
Pietro Albini [Tue, 5 Nov 2019 13:37:07 +0000 (14:37 +0100)]
Rollup merge of #66082 - GuillaumeGomez:cleanup-highlightsourcelines, r=kinnison
clean highlightSourceLines code
This is the first part of https://github.com/rust-lang/rust/issues/66046. Now that I've splitted the hashchange stuff and the source code lines highlighting, I'll be able to fix the whole issue once and for all.
The `#[rustc_args_required_const]` attribute was added to `simd_shuffle*` in rust-lang/stdarch#825. This caused `promote_consts` to double-count its second argument when recording promotion candidates, which caused the promotion candidate compatibility check to fail.
Once `stdarch` is updated in-tree to include rust-lang/stdarch#825, all special logic around `simd_shuffle` can and should be removed.