This patch adds a `copysign` function to the float primitive types.
It is an exceptionally useful function for writing efficient numeric
code, as it often avoids branches, is auto-vectorizable, and there
are efficient intrinsics for most platforms.
I think this might work as-is, as the relevant `copysign` intrinsic
is already used internally for the implementation of `signum`. It's
possible that an implementation might be needed in japaric/libm for
portability across all platforms, in which case I'll do that also.
Part of the work towards #55107
NLL: change compare-mode=nll to use borrowck=migrate
Fixes#55118.
This PR is split into two parts:
The first commit is a minor change that fixes a flaw in the existing `borrowck=migrate` implementation whereby a lint that was promoted to an error in the AST borrow checker would result in the same lint from the NLL borrow checker being downgraded to a warning in migrate mode. This PR fixes this by ensuring lints are exempt from buffering in the NLL borrow checker.
The second commit updates `compiletest` to make the NLL compare mode use `-Z borrowck=migrate` rather than `-Z borrowck=mir`. The third commit shows all the test output changes that result from this.
r? @pnkfelix
Add filtering option to `rustc_on_unimplemented` and reword `Iterator` E0277 errors
- Add more targetting filters for arrays to `rustc_on_unimplemented` (Fix#53766)
- Detect one element array of `Range` type, which is potentially a typo:
`for _ in [0..10] {}` where iterating between `0` and `10` was intended.
(Fix#23141)
- Suggest `.bytes()` and `.chars()` for `String`.
- Suggest borrowing or `.iter()` on arrays (Fix#36391)
- Suggest using range literal when iterating on integers (Fix#34353)
- Do not suggest `.iter()` by default (Fix#50773, fix#46806)
- Add regression test (Fix#22872)
reject partial init and reinit of uninitialized data
Reject partial initialization of uninitialized structured types (i.e. structs and tuples) and also reject partial *reinitialization* of such types.
Fix#54986Fix#54499
cc #21232
rustdoc: don't prefer dynamic linking in doc tests
This is an attempt to address the regression in #54478
This may be a case where the cure is worse than the disease, at least in the short term...
cc @alexcrichton
resolve: Scale back hard-coded extern prelude additions on 2015 edition
https://github.com/rust-lang/rust/pull/54404 stabilized `feature(extern_prelude)` on 2015 edition, including the hard-coded parts not passed with `--extern`.
First of all, I'd want to confirm that this is intended stabilization, rather than a part of the "extended beta" scheme that's going to be reverted before releasing stable.
(EDIT: to clarify - this is a question, I'm \*asking\* for confirmation, rather than give it.)
Second, on 2015 edition extern prelude is not so fundamentally tied to imports and is a mere convenience, so this PR scales them back to the uncontroversial subset.
The "uncontroversial subset" means that if libcore is injected it brings `core` into prelude, if libstd is injected it brings `std` and `core` into prelude.
On 2015 edition this can be implemented through the library prelude (rather than hard-coding in the compiler) right now, I'll do it in a follow-up PR.
UPDATE: The change is done for both 2015 and 2018 editions now as discussed below.
Closes https://github.com/rust-lang/rust/issues/53166
nll type annotations in multisegment path
This turned out to be sort of tricky. The problem is that if you have a path like
```
<Foo<&'static u32>>::bar
```
and it comes from an impl like `impl<T> Foo<T>` then the self-type the user gave doesn't *directly* map to the substitutions that the impl wants. To handle this, then, we have to preserve not just the "user-given substs" we used to do, but also a "user-given self-ty", which we have to apply later. This PR makes those changes.
It also removes the code from NLL relate-ops that handled canonical variables and moves to use normal inference variables instead. This simplifies a few things and gives us a bit more flexibility (for example, I predict we are going to have to start normalizing at some point, and it would be easy now).
r? @matthewjasper -- you were just touching this code, do you feel comfortable reviewing this?
Fixes#54574
This commit updates the test output for the updated NLL compare mode
that uses `-Z borrowck=migrate` rather than `-Z borrowck=mir`. The
previous commit changes `compiletest` and this commit only updates
`.nll.stderr` files.
This commit changes the NLL compare mode to pass `-Z borrowck=migrate`
rather than `-Z borrowck=nll` to better test what will be deployed. It
does not include the test output updates, as separation of these commits
makes reviewing simpler.
When lints are emitted from the AST borrow checker, they do not signal
an error as it is not known at that time whether, due to attributes,
that lint will error or warn. This means that when lints are buffered
in the MIR they will always be downgraded, as the AST borrowck will not
have been marked as having errored, even if a lint was upgraded to
an error after being emitted from the AST borrowck. The simple solution
to this is to not buffer any lints from the MIR borrowck.
Make `bad_style` a silent alias for `nonstandard_style`
Now only `nonstandard_style` is suggested in `rustc -W help`, but `bad_style` will not produce a warning. Closes#41646.
r? @Manishearth
