Re-enable trivial bounds
cc #50825
Remove implementations from global bounds in winnowing when there is ambiguity.
This results in the reverse of #24066 happening sometimes. I'm not sure if anything can be done about that though.
cc #48214
r? @nikomatsakis
Rollup of 13 pull requests
Successful merges:
- #50143 (Add deprecation lint for duplicated `macro_export`s)
- #51099 (Fix Issue 38777)
- #51276 (Dedup auto traits in trait objects.)
- #51298 (Stabilize unit tests with non-`()` return type)
- #51360 (Suggest parentheses when a struct literal needs them)
- #51391 (Use spans pointing at the inside of a rustdoc attribute)
- #51394 (Use scope tree depths to speed up `nearest_common_ancestor`.)
- #51396 (Make the size of Option<NonZero*> a documented guarantee.)
- #51401 (Warn on `repr` without hints)
- #51412 (Avoid useless Vec clones in pending_obligations().)
- #51427 (compiletest: autoremove duplicate .nll.* files (#51204))
- #51436 (Do not require stage 2 compiler for rustdoc)
- #51437 (rustbuild: generate full list of dependencies for metadata)
Failed merges:
rustbuild: generate full list of dependencies for metadata
Previously, we didn't send --features to our cargo metadata invocations,
and thus missed some dependencies that we enable through the --features
mechanism.
Do not require stage 2 compiler for rustdoc
r? @QuietMisdreavus
Fixes https://github.com/rust-lang/rust/issues/51424
I *think* this is correct; though I'm not certain. If it passes CI though I expect that to be good enough...
compiletest: autoremove duplicate .nll.* files (#51204)
UI tests in bless mode should now check to see if `.nll.*` files have a
matching `.*` file. If a match is found, it will be deleted.
This should be extensible to other modes (i.e., Polonius).
On running with `--bless`, the two files removed in #51186 are, in turn,
removed automatically.
fixes#51204
Avoid useless Vec clones in pending_obligations().
The only instance of `ObligationForest` in use has an obligation type of
`PendingPredicateObligation`, which contains a `PredicateObligation` and a
`Vec<Ty>`.
`FulfillmentContext::pending_obligations()` calls
`ObligationForest::pending_obligations()`, which clones all the
`PendingPredicateObligation`s. But the `Vec<Ty>` field of those cloned
obligations is never touched.
This patch changes `ObligationForest::pending_obligations()` to
`map_pending_obligations` -- which gives callers control about which part
of the obligation to clone -- and takes advantage of the change to avoid
cloning the `Vec<Ty>`. The change speeds up runs of a few rustc-perf
benchmarks, the best by 1%.
Make the size of Option<NonZero*> a documented guarantee.
Closes#49137, the tracking issue for `NonZero*`, as this was the last remaining open question.
Note that `ptr::NonNull<T>` already documents a similar guarantee.
Use scope tree depths to speed up `nearest_common_ancestor`.
This patch adds depth markings to all entries in the `ScopeTree`'s
`parent_map`. This change increases memory usage somewhat, but permits a
much faster algorithm to be used:
- If one scope has a greater depth than the other, the deeper scope is
moved upward until they are at equal depths.
- Then we move the two scopes upward in lockstep until they match.
This avoids the need to keep track of which scopes have already been
seen, which was the major part of the cost of the old algorithm. It also
reduces the number of child-to-parent moves (which are hash table
lookups) when the scopes start at different levels, because it never
goes past the nearest common ancestor the way the old algorithm did.
Finally, the case where one of the scopes is the root is now handled in
advance, because that is moderately common and lets us skip everything.
This change speeds up runs of several rust-perf benchmarks, the best by
6%.
A selection of the bigger improvements:
```
clap-rs-check
avg: -2.6% min: -6.6% max: 0.0%
syn-check
avg: -2.2% min: -5.0% max: 0.0%
style-servo-check
avg: -2.9%? min: -4.8%? max: 0.0%?
cargo-check
avg: -1.3% min: -2.8% max: 0.0%
sentry-cli-check
avg: -1.0% min: -2.1% max: 0.0%
webrender-check
avg: -0.9% min: -2.0% max: 0.0%
style-servo
avg: -0.9%? min: -1.8%? max: -0.0%?
ripgrep-check
avg: -0.7% min: -1.8% max: 0.1%
clap-rs
avg: -0.9% min: -1.6% max: -0.2%
regex-check
avg: -0.2% min: -1.3% max: 0.1%
syn
avg: -0.6% min: -1.3% max: 0.1%
hyper-check
avg: -0.5% min: -1.1% max: 0.0%
```
The idea came from multiple commenters on my blog and on Reddit. Thank you!
r? @nikomatsakis
Use spans pointing at the inside of a rustdoc attribute
Follow up to #51111.
Point to the link in a rustdoc attribute where intralink resolution failed, instead of the full rustdoc attribute's span.
r? @GuillaumeGomez cc @kennytm
Suggest parentheses when a struct literal needs them
When writing a struct literal in an expression that expects a block to
be started afterwards (like an `if` statement), do not suggest using the
same struct literal:
```
did you mean `S { /* fields * /}`?
```
Instead, suggest surrounding the expression with parentheses:
```
did you mean `(S { /* fields * /})`?
```
Fix#47360, #50090. Leaving #42982 open to come back to this problem with a better solution.
Dedup auto traits in trait objects.
Fixes#47010
Note that the test file `run-pass/trait-object-auto-dedup.rs` passes before and after this change. It's the `ui` test that changed from compiling to not compiling. Which does make this a breaking change, but I cannot imagine anybody actually being broken by it.
NLL: report type moved from behind borrow of array/slice
When NLL has illegal move due to borrowed content in an array or slice, provide feedback about why the move wasn't a copy.
Drive by: While comparing the resulting `.nll.stderr` files to their old borrowck variants, I noticed that the test for borrowck-vec-pattern-nesting.rs was not signaling some errors under NLL due to the test assuming lexical lifetimes. So I fixed that too.
Fix#51190
Removes extra global bounds at the winnowing stage rather than when
normalizing the param_env. This avoids breaking inference when there is
a global bound.
Previously, we didn't send --features to our cargo metadata invocations,
and thus missed some dependencies that we enable through the --features
mechanism.
UI tests in bless mode should now check to see if `.nll.*` files have a
matching `.*` file. If a match is found, it will be deleted.
This should be extensible to other modes (i.e., Polonius).
On running with `--bless`, the two files removed in #51186 are, in turn,
removed automatically.
Tries to address the recent network issues
1. Set the DNS server to 8.8.8.8/8.8.4.4/1.1.1.1/1.0.0.1 to workaround the daily "Cannot resolve host" error these two weeks.
2. Remove the unnecessary command `gem update --system` (originally added as experiment of the "Could not find a valid gem" error, which turns out to be useless).
Deny #[cfg] and #[cfg_attr] on generic parameters.
Fix#51279.
Attributes on generic parameters are not expanded, meaning `#[cfg]`, `#[cfg_attr]` and attribute proc macros are entirely ignored on them.
This PR makes using the first two attributes an error, because if they are correctly expanded will affect the AST and change code behavior.
I'm beta-nominating this, because generic parameter attributes are stabilizing in 1.27, and if we did not reserve their usage, we may never be able to repurpose the meaning of these attributes in the Rust 2015 edition.
Remove two redundant .nll.stderr files
It turns out that the diagnostics generated from NLL for these cases are now exactly the same as that produced by AST borrowck, and thus we can just fallback on those `.stderr` files that already exist for AST-borrowck.
Bravo!
(it is a good idea to remove these files, because it slightly reduces the amount of time humans will spend reviewing the .nll.stderr fileset...)
((it *might* be worthwhile trying to change the `compiletest` code to even issue a warning when two such files have equivalent contents... but I am not going so far as to try to implement that right now...))
The only instance of `ObligationForest` in use has an obligation type of
`PendingPredicateObligation`, which contains a `PredicateObligation` and a
`Vec<Ty>`.
`FulfillmentContext::pending_obligations()` calls
`ObligationForest::pending_obligations()`, which clones all the
`PendingPredicateObligation`s. But the `Vec<Ty>` field of those cloned
obligations is never touched.
This patch changes `ObligationForest::pending_obligations()` to
`map_pending_obligations` -- which gives callers control about which part
of the obligation to clone -- and takes advantage of the change to avoid
cloning the `Vec<Ty>`. The change speeds up runs of a few rustc-perf
benchmarks, the best by 1%.
Guillaume Gomez