Docs: put Future trait into spotlight
If a function returns a type that implements `Future`, there should be a small "i" symbol next to it indicating the return type implements an important trait.
Search for target_triple.json only if builtin target not found
Before this commit, if the builtin target was found, but an error
happened when instantiating it (e.g. validating the target
specification file failed, etc.), then we ignored those errors
and proceeded to try to find a `target_triple.json` file, and if
that failed, reported that as an error.
With this commit, if rustc is supposed to provide the builtin target,
and something fails while instantiating it, that error will
get properly propagated.
r? @oli-obk
Add a note about 2018e if someone uses `try {` in 2015e
Inspired by https://github.com/rust-lang/rust/issues/58491, where a `try_blocks` example was accidentally run in 2015, which of course produces a bunch of errors.
What's the philosophy about gating for this? The keyword is stably a keyword in 2018, so I haven't gated it for now but am not mentioning what the keyword _does_. Let me know if I should do differently.
Resolves#53672
fix overlapping references in BTree
This fixes two kinds of overlapping references in BTree (both found by running the BTree test suite in Miri).
In `into_slices_mut`, we did `k.into_key_slice_mut()` followed by `self.into_val_slice_mut()` (where `k` is a copy of `self`). Calling `into_val_slice_mut` calls `self.len()`, which creates a shared reference to `NodeHeader`, which unfortunately (due to padding) overlaps with the mutable reference returned by `into_key_slice_mut`. Hence the key slice got (partially) invalidated. The fix is to avoid creating an `&NodeHeader` after the first slice got created.
In the iterators, we used to first create the references that will be returned, and then perform the walk on the tree. Walking the tree creates references (such as `&mut InternalNode`) that overlap with all of the keys and values stored in a pointer; in particular, they overlap with the references the iterator will later return. This is fixed by reordering the operations of walking the tree and obtaining the inner references.
The test suite still passes (and it passes in Miri now!), but there is a lot of code here that I do not understand...
override `VecDeque::try_rfold`, also update iterator
This keeps the slice based iteration and updates the iterator state after each slice. It also uses a loop to reduce the amount of code.
This uses unsafe code, so some thorough review would be appreciated. Cc @RalfJung
improve Pin documentation
Incorporates a bunch of the documentation-related comments that came up when discussing `Pin` stabilization.
Cc @alexcrichton @withoutboats @cramertj @jonhoo
Fixes https://github.com/rust-lang/rust/issues/58130
Re-implement leak check in terms of universes
This PR temporarily restores the leak-check, but implemented in terms of universes. This is not because the leak check behavior was necessarily **correct**, but because (a) we may want to have a transition period and because (b) we want to have more breathing room to work through the full implications of handling higher-ranked types correctly. Note that this PR builds atop https://github.com/rust-lang/rust/pull/58056.
Fixes#58451Fixes#46989Fixes#57639
r? @aturon
cc @arielb1, @lqd
~~Temporary note: I've not finished running `./x.py test` locally -- I'm confident a lot of error messages in tests will need updating. I sort of expect them to revert to the older, (imo) less good error messages, which is mildly unfortunate. There might be a way to preserve the new error messages, not sure.~~
Update cargo
9 commits in 865cb70106a6b1171a500ff68f93ab52eea56e72..b33ce7fc9092962b0657b4c25354984b5e5c47e4
2019-02-10 15:49:37 +0000 to 2019-02-19 18:42:50 +0000
- Don't retry invalid credentials from git credential helpers (rust-lang/cargo#6681)
- Fix some typos in resolver tests (rust-lang/cargo#6682)
- Add an unstable option to build proc macros for both the host and the target (rust-lang/cargo#6547)
- Test cases proving RUSTC_WRAPPER can be a relative path (rust-lang/cargo#6638)
- Add support for Azure DevOps (rust-lang/cargo#6264)
- Update docs for removed `patch` restriction. (rust-lang/cargo#6663)
- Fix incorrect help message (rust-lang/cargo#6555)
- Stabilize Alternative Registries (rust-lang/cargo#6654)
- Having a [patch] section when publishing is not an error (rust-lang/cargo#6535)
The solution which uses braces to release the borrow
before it is moved is only required to satisfy the 2015
edition borrow checker.
All other examples give the expected results for both
2015 and 2018 editions.
make generalization code create new variables in correct universe
In our type inference system, when we "generalize" a type T to become
a suitable value for a type variable V, we sometimes wind up creating
new inference variables. So, for example, if we are making V be some
subtype of `&'X u32`, then we might instantiate V with `&'Y u32`.
This generalized type is then related `&'Y u32 <: &'X u32`, resulting
in a region constriant `'Y: 'X`. Previously, however, we were making
these fresh variables like `'Y` in the "current universe", but they
should be created in the universe of V. Moreover, we sometimes cheat
in an invariant context and avoid creating fresh variables if we know
the result must be equal -- we can only do that when the universes
work out.
Fixes#57843
r? @pnkfelix
Before this commit, if the builtin target was found, but an error
happened when instantiating it (e.g. validating the target
specification file failed, etc.), then we ignored those errors
and proceeded to try to find a `target_triple.json` file, and if
that failed, reported that as an error.
With this commit, if rustc is supposed to provide the builtin target,
and something fails while instantiating it, that error will
get properly propagated.
