Expand long-live-borrows-in-boxes test to include simplier illustrative cases.
After talking about the PR with eddyb, I decided it was best to try to
have some test cases that simplify the problem down to its core, so
that people trying to understand what the issue is here will see those
core examples first.
(Presumably the place that borrow_check ends up reporting for the
error about is no longer the root `Local` itself, and thus the note
diagnostic here stops firing.)
Since we know dropping a box will not access any `&mut` or `&`
references, it is safe to model its destructor as only touching the
contents *owned* by the box.
Note: At some point we may want to generalize this machinery to other
reference and collection types that are "pure" in the same sense as
box. If we add a `&move` reference type, it would probably also fall
into this branch of code. But for the short term, we will be
conservative and restrict this change to `Box<T>` alone.
The code works by recursively descending a deref of the `Box`. We
prevent `visit_terminator_drop` infinite-loop (which can arise in a
very obscure scenario) via a linked-list of seen types.
Note: A similar style stack-only linked-list definition can be found
in `rustc_mir::borrow_check::places_conflict`. It might be good at
some point in the future to unify the two types and put the resulting
definition into `librustc_data_structures/`.
----
One final note: Review feedback led to significant simplification of
logic here.
During review, eddyb RalfJung and I uncovered the heart of why I
needed a so-called "step 2" aka the Shallow Write to the Deref of the
box. It was because the `visit_terminator_drop`, in its base case,
will not emit any write at all (shallow or deep) to a place unless
that place has a need_drop.
So I was encoding a Shallow Write by hand for a `Box<T>`, as a
separate step from recursively descending through `*a_box` (which was
at the time known as "step 1"; it is now the *only* step, apart from
the change to the base case for `visit_terminator_drop` that this
commit now has encoded).
eddyb aruged that *something* should be emitting some sort of write in
the base case here (even a shallow one), of the dropped place, since
by analogy we also emit a write when you *move* a place. That led
to the revision here in this commit.
* (Its possible that this desired write should be attached in some
manner to StorageDead instead of Drop. But in this PR, I tried to
leave the StorageDead logic alone and focus my attention solely on
how Drop(x) is modelled in MIR-borrowck.)
bors [Wed, 1 Aug 2018 11:38:20 +0000 (11:38 +0000)]
Auto merge of #52474 - alexcrichton:better-lto-error, r=eddyb
rustc: Handle linker diagnostics from LLVM
Previously linker diagnostic were being hidden when two modules were linked
together but failed to link. This commit fixes the situation by ensuring that we
have a diagnostic handler installed and also adds support for handling linker
diagnostics.
bors [Wed, 1 Aug 2018 08:41:36 +0000 (08:41 +0000)]
Auto merge of #52937 - pietroalbini:rollup, r=pietroalbini
Rollup of 30 pull requests
Successful merges:
- #52340 (Document From trait implementations for OsStr, OsString, CString, and CStr)
- #52628 (Cleanup some rustdoc code)
- #52732 (Remove unstable and deprecated APIs)
- #52745 (Update clippy to latest master)
- #52771 (Clarify thread::park semantics)
- #52778 (Improve readability of serialize.rs)
- #52810 ([NLL] Don't make "fake" match variables mutable)
- #52821 (pretty print for std::collections::vecdeque)
- #52822 (Fix From<LocalWaker>)
- #52824 (Fix -Wpessimizing-move warnings in rustllvm/PassWrapper)
- #52825 (Make sure #47772 does not regress)
- #52831 (remove references to AUTHORS.txt file)
- #52842 (update comment)
- #52846 (Add timeout to use of `curl` in bootstrap.py.)
- #52851 (Make the tool_lints actually usable)
- #52853 (Improve bootstrap help on stages)
- #52859 (Use Vec::extend in SmallVec::extend when applicable)
- #52861 (Add targets for HermitCore (https://hermitcore.org) to the Rust compiler and port libstd to it.)
- #52867 (releases.md: fix 2 typos)
- #52870 (Implement Unpin for FutureObj and LocalFutureObj)
- #52876 (run-pass/const-endianness: negate before to_le())
- #52878 (Fix wrong issue number in the test name)
- #52883 (Include lifetime in mutability suggestion in NLL messages)
- #52888 (Use suggestions for shell format arguments)
- #52904 (NLL: sort diagnostics by span)
- #52905 (Fix a typo in unsize.rs)
- #52907 (NLL: On "cannot move out of type" error, print original before rewrite)
- #52914 (Only run the sparc-abi test on sparc)
- #52918 (Backport 1.27.2 release notes)
- #52929 (Update compatibility note for 1.28.0 to be correct)
Pietro Albini [Wed, 1 Aug 2018 08:13:10 +0000 (10:13 +0200)]
Rollup merge of #52929 - Havvy:patch-1, r=alexcrichton
Update compatibility note for 1.28.0 to be correct
You can still put implementations on `dyn Trait + Send + Send`, but it'd be the same as putting them on `dyn Trait + Send`. This is why the error is that there are duplicate definitions in the example.
Pietro Albini [Wed, 1 Aug 2018 08:13:07 +0000 (10:13 +0200)]
Rollup merge of #52914 - nagisa:sparc-is-sparc’s-own-business, r=alexcrichton
Only run the sparc-abi test on sparc
It is not required for LLVM to have SPARC target support, so it is
necessary to only run this test when LLVM does support SPARC. Sadly, it
isn’t possible to specify exactly this constraint. Instead, we specify
that this test should run on SPARC host only (it surely is sane
assumption to make that compiler running on a SPARC can generate
SPARC, right?)
Since you cannot specify multiple `only-*` to have it run on both 32-bit
and 64-bit SPARC we pick 64-bit SPARC, because it is exactly what is
being tested by this test.
Pietro Albini [Wed, 1 Aug 2018 08:13:06 +0000 (10:13 +0200)]
Rollup merge of #52907 - pnkfelix:issue-52877-original-source-should-precede-suggestions, r=petrochenkov
NLL: On "cannot move out of type" error, print original before rewrite
NLL: On "cannot move out of type" error, print original source before rewrite.
* Arguably this change is sometimes injecting noise into the output (namely in the cases where the suggested rewrite is inline with the suggestion and we end up highlighting the original source code). I would not be opposed to something more aggressive/dynamic, like revising the suggestion code to automatically print the original source when necessary (e.g. when the error does not have a span that includes the span of the suggestion).
* Also, as another note on this change: The doc comment for `Diagnostic::span_suggestion` says:
```rust
/// The message
///
/// * should not end in any punctuation (a `:` is added automatically)
/// * should not be a question
/// * should not contain any parts like "the following", "as shown"
```
* but the `:` is *not* added when the emitted line appears out-of-line relative to the suggestion. I find that to be an unfortunate UI experience.
----
As a drive-by fix, also changed code to combine multiple suggestions for a pattern into a single multipart suggestion (which vastly improves user experience IMO).
Pietro Albini [Wed, 1 Aug 2018 08:13:04 +0000 (10:13 +0200)]
Rollup merge of #52904 - pnkfelix:issue-51167-sort-by-span, r=petrochenkov
NLL: sort diagnostics by span
Sorting the output diagnostics by span is a long planned revision to the NLL diagnostics that we hope will yield a less surprising user experience in some case.
Once we got them buffered, it was trivial to implement. (The hard part is skimming the resulting changes to the diagnostics to make sure nothing broke... Note that I largely rubber-stamped the `#[rustc_regions]` output change.)
Pietro Albini [Wed, 1 Aug 2018 08:12:58 +0000 (10:12 +0200)]
Rollup merge of #52876 - cuviper:const-endianness-be, r=kennytm
run-pass/const-endianness: negate before to_le()
`const LE_I128` needs parentheses to negate the value *before* calling
`to_le()`, otherwise it doesn't match the operations performed in the
black-boxed part of the test. This only makes a tangible difference on
big-endian targets.
Pietro Albini [Wed, 1 Aug 2018 08:12:55 +0000 (10:12 +0200)]
Rollup merge of #52861 - ColinFinck:master, r=alexcrichton
Add targets for HermitCore (https://hermitcore.org) to the Rust compiler and port libstd to it.
As a start, the port uses the simplest possible configuration (no jemalloc, abort on panic) and makes use of existing Unix-specific code wherever possible.
It adds targets for x86_64 (current main HermitCore platform) and aarch64 (HermitCore platform under development).
Together with the patches to "liblibc" (https://github.com/rust-lang/libc/pull/1048) and llvm (https://github.com/rust-lang/llvm/pull/122), this enables HermitCore applications to be written in Rust.
Pietro Albini [Wed, 1 Aug 2018 08:12:54 +0000 (10:12 +0200)]
Rollup merge of #52859 - ljedrz:smallvec_true_extend, r=Mark-Simulacrum
Use Vec::extend in SmallVec::extend when applicable
As calculated in #52738, `Vec::extend` is much faster than `push`ing to it in a loop. We can take advantage of this method in `SmallVec` too - at least in cases when its underlying object is an `AccumulateVec::Heap`.
~~This approach also accidentally improves the `push` loop of the `AccumulateVec::Array` variant, because it doesn't utilize `SmallVec::push` which performs `self.reserve(1)` with every iteration; this is unnecessary, because we're already reserving the whole space we will be needing by performing `self.reserve(iter.size_hint().0)` at the beginning.~~
Pietro Albini [Wed, 1 Aug 2018 08:12:51 +0000 (10:12 +0200)]
Rollup merge of #52851 - flip1995:tool_lints, r=oli-obk
Make the tool_lints actually usable
cc #44690
Necessary for rust-lang-nursery/rust-clippy#2955 and rust-lang-nursery/rust-clippy#2977
This PR makes it possible for lint tools (at the moment only for Clippy) to implement the `tool_lints`, like it was documented in #52018.
Because the `declare_lint` macro is pretty cluttered right now, there was not really a good way to add the `tool_name` as an additional argument of the macro. That's why I chose to introduce the new `declare_tool_lint` macro.
The switch from `&str` to `String` in the `lint_groups` `FxHashMap` is because I got weird error messages in the `check_lint_name` method. And the `by_name` field of the `LintStore` also uses `String`.
### What comes with this PR:
If this PR lands and Clippy switches to the `tool_lints`, the currently used methods
```rust
#[cfg_attr(feature = "cargo-clippy", allow(clippy_lint))]
#[allow(unknown_lints, clippy_lint)]
```
to `allow`/`warn`/`deny`/`forbid` Clippy lints, won't have any effects anymore, but also won't produce a warning. That is because the name of `clippy_lint` will then be `clippy::clippy_lint`. (Maybe we can add a clippy lint to search for `cfg_attr` appearances with the `cargo-clippy` feature?)
Pietro Albini [Wed, 1 Aug 2018 08:12:50 +0000 (10:12 +0200)]
Rollup merge of #52846 - kennytm:bootstrap-curl-timeout, r=Mark-Simulacrum
Add timeout to use of `curl` in bootstrap.py.
Recently we've seen a lot of "30 minutes no output" spurious errors while downloading the bootstrap compiler. This added several timeout options so if the "30 minutes no output" errors were caused by connection or transfer issue, we could fail quicker for curl to retry.
Pietro Albini [Wed, 1 Aug 2018 08:12:37 +0000 (10:12 +0200)]
Rollup merge of #52745 - commandline:master, r=oli-obk
Update clippy to latest master
r? @oli-obk
There is a regression in the version in current nightly that falsely lints `println!` and `writeln!` that use named arguments, thinking all rhs values for the argument expressions are literals even when they are not. This update includes the fix for that.
bors [Wed, 1 Aug 2018 06:44:09 +0000 (06:44 +0000)]
Auto merge of #52756 - alexcrichton:cap-applicable, r=oli-obk
rustc: Disallow machine applicability in foreign macros
Recent changes to lints disallowed lints from being emitted against code located
in foreign macros, except for future-incompatible lints. For a future
incompatible lint, however, the automatic suggestions may not be applicable!
This commit updates this code path to force all applicability suggestions made
to foreign macros to never be `MachineApplicable`. This should avoid rustfix
actually attempting fixing these suggestions, causing non-compiling code to be
produced.
Based on https://github.com/rust-lang/rust/pull/50911, cc https://github.com/rust-lang/rust/pull/50911#issuecomment-401151270
`#[macro_export] macro_rules` items are collected from the whole crate and are planted into the root module as items, so the external view of the crate is symmetric with its internal view and something like `$crate::my_macro` where `my_macro` is `#[macro_export] macro_rules` works both locally and from other crates.
It is not required for LLVM to have SPARC target support, so it is
necessary to only run this test when LLVM does support SPARC. Sadly, it
isn’t possible to specify exactly this constraint. Instead, we specify
that this test should run on SPARC host only (it surely is sane
assumption to make that compiler running on a SPARC can generate
SPARC, right?)
Since you cannot specify multiple `only-*` to have it run on both 32-bit
and 64-bit SPARC we pick 64-bit SPARC, because it is exactly what is
being tested by this test.
Alex Crichton [Tue, 17 Jul 2018 23:20:51 +0000 (16:20 -0700)]
rustc: Handle linker diagnostic from LLVM
Previously linker diagnostic were being hidden when two modules were linked
together but failed to link. This commit fixes the situation by ensuring that we
have a diagnostic handler installed and also adds support for handling linker
diagnostics.
Mark Rousskov [Sat, 21 Jul 2018 22:12:16 +0000 (16:12 -0600)]
Pull out nightly checking to edges
Parsing the code block's LangString (```foo) previously checked itself
to see if we were on nightly; that isn't the right place to do so. Move
that check slightly outwards to better abstract LangString.
(This is also an optimization as we avoid the costly environment
variable load of RUSTC_BOOTSTRAP).
NLL: On "cannot move out of type" error, print original source before rewrite.
* Arguably this change is sometimes injecting noise into the output
(namely in the cases where the suggested rewrite is inline with the
suggestion and we end up highlighting the original source code).
I would not be opposed to something more aggressive/dynamic, like
revising the suggestion code to automatically print the original
source when necessary (e.g. when the error does not have a span
that includes the span of the suggestion).
* Also, as another note on this change: The doc comment for `Diagnostic::span_suggestion`
says:
/// The message
///
/// * should not end in any punctuation (a `:` is added automatically)
/// * should not be a question
/// * should not contain any parts like "the following", "as shown"
but the `:` is *not* added when the emitted line appears
out-of-line relative to the suggestion. I find that to be an
unfortunate UI experience.
----
As a drive-by fix, also changed code to combine multiple suggestions
for a pattern into a single multipart suggestion (which vastly
improves user experience IMO).
Auto merge of #52850 - SimonSapin:unstablize, r=alexcrichton
Revert "Stabilize to_bytes and from_bytes for integers."
This reverts commit c8f9b84b393915a48253e3edc862c15a9b7152a7 / PR https://github.com/rust-lang/rust/pull/51835, and reopens the tracking issue https://github.com/rust-lang/rust/issues/49792.
These methods were stabilized in Rust 1.29, which is still in Nightly as of this writing. So my understanding is that it is still time to change our minds. Given the ongoing discussion in https://github.com/rust-lang/rust/pull/51919 about possibly renaming these APIs and since 1.29 goes to beta soon, I’d like to revert this stabilization for now until a decision is made in that PR. It’s possible that a decision will be made in time for 1.29, but there is no urgency. At most I expect this functionality to make it into 1.30.
Auto merge of #52630 - Mark-Simulacrum:rustdoc-cleanup-2, r=QuietMisdreavus
Delete unused code in rustdoc
Also hid the unused crate exports of rustdoc. This is technically a breaking change but we don't even ship librustdoc in the sysroot so I don't expect breakage.
Josh Stone [Mon, 30 Jul 2018 20:08:56 +0000 (13:08 -0700)]
run-pass/const-endianness: negate before to_le()
`const LE_I128` needs parentheses to negate the value *before* calling
`to_le()`, otherwise it doesn't match the operations performed in the
black-boxed part of the test. This only makes a tangible difference on
big-endian targets.