In the 2018 edition, when suggesting traits to import that implement a
given method that is being invoked, suggestions will now include the
`crate::` prefix if the suggested trait is local to the current crate.
This commit improves mutability error suggestions by suggesting the
removal of `&mut` where a mutable borrow is being taken of a `&mut self`
or a `self: &mut Self`.
This commit adds an `ImplicitSelfKind` to the HIR and the MIR that keeps
track of whether a implicit self argument is immutable by-value, mutable
by-value, immutable reference or mutable reference so that the addition
of the `mut` keyword can be suggested for the immutable by-value case.
do not normalize all non-scalar constants to a ConstValue::ScalarPair
We still need `ConstValue::ScalarPair` for match handling (matching slices and strings), but that will never see anything `Undef`. For non-fat-ptr `ScalarPair`, just point to the allocation like larger data structures do.
Fixes https://github.com/rust-lang/rust/issues/54387
r? @eddyb
This commit special cases the move out of borrowed content error,
previously:
```
error[E0507]: cannot move out of borrowed content
--> src/main.rs:7:10
|
7 | drop(x.field);
| ^ cannot move out of borrowed content
```
to instead mention that it is a move out of a `Rc`/`Arc` which is more
helpful:
```
error[E0507]: cannot move out of an `Rc`
--> src/main.rs:7:10
|
7 | drop(x.field);
| ^ cannot move out of an `Rc`
```
Remove `-Z disable_ast_check_for_mutation_in_guard`
One should use `#![feature(bind_by_move_pattern_guards)]` over `-Z disable_ast_check_for_mutation_in_guard`
cc #15287
Don't lint non-extern-prelude extern crate's in Rust 2018.
Fixes#54381 by silencing the lint telling users to remove `extern crate` when `use` doesn't work.
r? @alexcrichton cc @petrochenkov @nikomatsakis @Centril
Add a per-tree error cache to the obligation forest
This implements part of what @nikomatsakis mentioned in https://github.com/rust-lang/rust/pull/30533#issuecomment-170705871:
> 1. If you find that a new obligation is a duplicate of one already in the tree, the proper processing is:
> * if that other location is your parent, you should abort with a cycle error (or accept it, if coinductive)
> * if that other location is not an ancestor, you can safely ignore the new obligation
In particular it implements the "if that other location is your parent accept it, if coinductive" part. This fixes#40827.
I have to say that I'm not 100% confident that this is rock solid. This is my first pull request 🎉, and I didn't know anything about the trait resolver before this. In particular I'm not totally sure that comparing predicates is enough (for instance, do we need to compare `param_env` as well?). Also, I'm not sure what @nikomatsakis mentions [here](https://github.com/rust-lang/rust/issues/30977#issue-127091096), but it might be something that affects this PR:
> In particular, I am wary of getting things wrong around inference variables! We can always add things to the set in their current state, and if unifications occur then the obligation is just kind of out-of-date, but I want to be sure we don't accidentally fail to notice that something is our ancestor. I decided this was subtle enough to merit its own PR.
Anyway, go ahead and review 🙂.
Ref #30977.
# Performance
We are now copying vectors around, so I decided to do some benchmarking. A simple benchmark shows that this does not seem to affect performance in a measurable way:
I ran `cargo clean && cargo build` 20 times on actix-web (84b27db) and these are the results:
```text
rustc master:
Mean Std.Dev. Min Median Max
real 66.637 2.996 57.220 67.714 69.314
user 307.293 14.741 258.093 312.209 320.702
sys 12.524 0.653 10.499 12.726 13.193
rustc fix-bug-overflow-send:
Mean Std.Dev. Min Median Max
real 66.297 4.310 53.532 67.516 70.348
user 306.812 22.371 236.917 314.748 326.229
sys 12.757 0.952 9.671 13.125 13.544
```
I will do a more comprehensive benchmark (compiling rustc stage1) and post the results.
r? @nikomatsakis, @nnethercote
PS: It is better to review this commit-by-commit.
Enable NLL compare mode for more tests
Most of these tests were disabled due to NLL bugs that have since been fixed. A few needed updating for NLL.
r? @nikomatsakis
use closure def-id in returns, but base def-id in locals
The refactorings to handle `let x: impl Trait` wound up breaking `impl Trait` in closure return types. I think there are some deeper problems with the code in question, but this a least should make @eddyb's example work.
Fixes#54593
r? @eddyb
Rollup of 8 pull requests
Successful merges:
- #54564 (Add 1.29.1 release notes)
- #54567 (Include path in stamp hash for debuginfo tests)
- #54577 (rustdoc: give proc-macros their own pages)
- #54590 (std: Don't let `rust_panic` get inlined)
- #54598 (Remove useless lifetimes from `Pin` `impl`s.)
- #54604 (Added help message for `self_in_typedefs` feature gate)
- #54635 (Improve docs for std::io::Seek)
- #54645 (Compute Android gdb version in compiletest)
rustc: keep a Span for each predicate in ty::GenericPredicates.
This should allow finer-grained diagnostics, including migration suggestions for #54090.
(Note that I haven't changed most of the users of `predicates_of` to use the new spans)
r? @nikomatsakis
codegen_llvm: check inline assembly constraints with LLVM
---%<---
Hey all,
As issue #54130 highlights, constraints are not checked and passing bad constraints to LLVM can crash it since a `Verify()` call is placed inside an assertion (see: `src/llvm/lib/IR/InlineAsm.cpp:39`).
As this is my first PR to the Rust compiler (woot! 🎉), there might be better ways of achieving this result. In particular, I am not too happy about generating an error in codegen; it would be much nicer if we did it earlier. However, @rkruppe [noted on IRC](https://botbot.me/mozilla/rustc/2018-09-25/?msg=104791581&page=1) that this should be fine for an unstable feature and a much better solution than the _status quo_, which is an ICE.
Thanks!
--->%---
LLVM provides a way of checking whether the constraints and the actual
inline assembly make sense. This commit introduces a check before
emitting code for the inline assembly. If LLVM rejects the inline
assembly (or its constraints), then the compiler emits an error E0668
("malformed inline assembly").
Fixes: #54130
Signed-off-by: Levente Kurusa \<lkurusa@acm.org\>
Use full name to identify a macro in a `FileName`.
Before this two macros with same name would be indistinguishable inside a `FileName`. This caused a bug in incremental compilation (see #53097) since two different macros would map out to the same `StableFilemapId`.
Fixes#53097.
r? @nrc
RFC 2093 (tracking issue #44493) lets us leave off
commonsensically inferable `T: 'a` outlives requirements. (A separate
feature-gate was split off for the case of 'static lifetimes, for
which questions still remain.) Detecting these was requested as an
idioms-2018 lint.
It turns out that issuing a correct, autofixable suggestion here is
somewhat subtle in the presence of other bounds and generic
parameters. Basically, we want to handle these three cases:
• One outlives-bound. We want to drop the bound altogether, including
the colon—
MyStruct<'a, T: 'a>
^^^^ help: remove this bound
• An outlives bound first, followed by a trait bound. We want to
delete the outlives bound and the following plus sign (and
hopefully get the whitespace right, too)—
MyStruct<'a, T: 'a + MyTrait>
^^^^^ help: remove this bound
• An outlives bound after a trait bound. We want to delete the
outlives lifetime and the preceding plus sign—
MyStruct<'a, T: MyTrait + 'a>
^^^^^ help: remove this bound
This gets (slightly) even more complicated in the case of where
clauses, where we want to drop the where clause altogether if there's
just the one bound. Hopefully the comments are enough to explain
what's going on!
A script (in Python, sorry) was used to generate the
hopefully-sufficiently-exhaustive UI test input. Some of these are
split off into a different file because rust-lang-nursery/rustfix#141
(and, causally upstream of that, #53934) prevents them from being
`run-rustfix`-tested.
We also make sure to include a UI test of a case (copied from RFC
2093) where the outlives-bound can't be inferred. Special thanks to
Niko Matsakis for pointing out the `inferred_outlives_of` query,
rather than blindly stripping outlives requirements as if we weren't a
production compiler and didn't care.
This concerns #52042.
Migrate `src/test/ui/run-pass/*` back to `src/test/run-pass/`.
Moves all the tests from `src/test/ui/run-pass/**` back to `src/test/run-pass/`.
This should have no impact on our overall testing completeness due to PR #54223Fix#54047
[NLL] Get Polonius borrow check to work in simple cases
* Restores the generation of outlives facts from subtyping.
* Restore liveness facts.
* Generate invalidates facts at the start point of each location,
where we check for errors.
* Add a small test for simple cases (previously these cases have compiled, and more recently ICEd).
Closes#54212
cc #53142 (will need test)
### Known limitations
* Two phase borrows aren't implemented for Polonius yet
* Invalidation facts haven't been updated for some of the recent changes to make `Drop` terminators access fewer things.
* Fact generation is not as optimized as it could be.
* Around 30 tests fail in compare mode, often tests that are ignored in nll compare mode
r? @nikomatsakis
NLL: regression test for "dropck: track order of destruction for r-value temporaries"
Once this lands, we can remove the E-needstest from #22323.
(We shouldn't close the bug itself, however, because we are leaving the NLL-fixed-by-NLL bugs open until NLL is turned on by default.)
