Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Rollup of 12 pull requests #66438

Merged
merged 29 commits into from
Nov 15, 2019
Merged

Rollup of 12 pull requests #66438

merged 29 commits into from
Nov 15, 2019

Conversation

JohnTitor
Copy link
Member

Successful merges:

Failed merges:

r? @ghost

haraldh and others added 29 commits October 22, 2019 16:52
Rename
* Error::iter_chain() -> Error::chain()
* ErrorIter -> Chain

Removed
* Error::iter_sources()

according to
rust-lang#58520

Rationale:

   1. Such iterators are helpful. They should better be stabilized sooner
      than later.
   2. self should be included. It is easy to .skip(1) it.
      Not including self is harmful because it is harder to add self
      to the iterator than to remove it.
   3. The chosen name should be telling and reflect the fact that self is
      included. `.chain()` was chosen because the iterator iterates over
      the chain of errors that is somehow included in self.
   4. The resulting iterator is named `Chain` because the `error::Chain`
      is what we want to have.
For a single-threaded parallel compiler, this reduces instruction counts
across several benchmarks, by up to 2.8%.

The commit also adds documentation about `Sharded`'s use of `FxHasher`.
The `Context` argument is currently smuggled through TLS for
async-generated futures. The current infrastructure is closure-based,
and results in an extra 6 stack frames when .awaiting an async-generated
future!

```
  12: foo::async_b::{{closure}}
             at src/main.rs:10
  13: <std::future::GenFuture<T> as core::future::future::Future>::poll::{{closure}}
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:43
  14: std::future::set_task_context
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:79
  15: <std::future::GenFuture<T> as core::future::future::Future>::poll
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:43
  16: std::future::poll_with_tls_context::{{closure}}
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:121
  17: std::future::get_task_context
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:111
  18: std::future::poll_with_tls_context
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:121
  19: foo::async_a::{{closure}}
             at src/main.rs:6
```

While the long (medium?) term solution is to remove the use of TLS
entirely, we can improve things a bit in the meantime. In particular,
this commit does 2 things:

1. `get_task_context` has been inlined into `poll_with_tls_context`,
    removing 2 frames (16 and 17 above).
2. `set_task_context` now returns a guard type that resets the TLS
    rather than taking a closure, removing 2 frames (13 and 14 above).

We can also remove frame 18 by removing `poll_with_tls_context` in favor
of a `get_task_context` function which returns a guard, but that
requires adjusting the code generated for .await, so I've left that off
for now.
Also move the declaration outside the loop since they accumulate state with each iteration
rename Error::iter_chain() and remove Error::iter_sources()

~~Rename~~
* ~~Error::iter_chain() -> Error::chained()~~
* ~~Error::iter_sources() -> Error::ancestors()~~
* ~~ErrorIter -> Chained and Ancestors~~

according to
rust-lang#58520 (comment)

Tracker:
rust-lang#58520

Edit:

Rename
* Error::iter_chain() -> Error::chained()
* ErrorIter -> Chain

So, it seems, that even Path::ancestors() includes itself. So, to avoid confusion and simplify it more, I reduced PR  rust-lang#65557 to only have `chained` and `Chain`.

Rationale:

   1. Such iterators are helpful. They should better be stabilized sooner than later.
   1. self should be included. It is easy to .skip(1) it.  Not including self is harmful because it is harder to add self to the iterator than to remove it.
   1. The chosen name should be telling and reflect the fact that self is included. `.chained()` was chosen in honor of error-chain and because the iterator iterates over the chain of errors that is somehow included in self.
   1. The resulting iterator is named `Chain` because the `error::Chain` is what we want to have.
…get_query, r=Zoxc

Avoid hashing the key twice in `get_query()`.

For a single-threaded parallel compiler, this reduces instruction counts
across several benchmarks, by up to 2.8%.

The commit also adds documentation about `Sharded`'s use of `FxHasher`.

r? @Zoxc
…miri, r=oli-obk

Remove cannot mutate statics in initializer of another static error

r? @oli-obk

This is just a refactoring. As the removed code itself said, it only a heuristic catching a few cases early instead of leaving it all to const eval. It's easy to work around the static check and then run into the miri-engine check.
Update mdbook.

This brings in some important updates to fix some rendering issues in the books. In particular fixing hidden lines in code blocks, and some escaping issues.  More details at https://github.com/rust-lang/mdBook/blob/master/CHANGELOG.md

This also requires updating mdbook-linkcheck.
Do not ICE on recovery from unmet associated type bound obligation

Fix rust-lang#66353.

r? @Centril
Fix ICE when trying to suggest `Type<>` instead of `Type()`

Fixes rust-lang#66286, but the output has no span:

```
error[E0214]: parenthesized type parameters may only be used with a `Fn` trait

error: aborting due to previous error

For more information about this error, try `rustc --explain E0214`.
```
Do not ICE in `if` without `else` in `async fn`

Fix rust-lang#66387.
Remove some stack frames from `.async` calls

The `Context` argument is currently smuggled through TLS for
async-generated futures. The current infrastructure is closure-based,
and results in an extra 6 stack frames when .awaiting an async-generated
future!

```
  12: foo::async_b::{{closure}}
             at src/main.rs:10
  13: <std::future::GenFuture<T> as core::future::future::Future>::poll::{{closure}}
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:43
  14: std::future::set_task_context
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:79
  15: <std::future::GenFuture<T> as core::future::future::Future>::poll
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:43
  16: std::future::poll_with_tls_context::{{closure}}
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:121
  17: std::future::get_task_context
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:111
  18: std::future::poll_with_tls_context
             at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/libstd/future.rs:121
  19: foo::async_a::{{closure}}
             at src/main.rs:6
```

While the long (medium?) term solution is to remove the use of TLS
entirely, we can improve things a bit in the meantime. In particular,
this commit does 2 things:

1. `get_task_context` has been inlined into `poll_with_tls_context`,
    removing 2 frames (16 and 17 above).
2. `set_task_context` now returns a guard type that resets the TLS
    rather than taking a closure, removing 2 frames (13 and 14 above).

We can also remove frame 18 by removing `poll_with_tls_context` in favor
of a `get_task_context` function which returns a guard, but that
requires adjusting the code generated for .await, so I've left that off
for now.
miri: helper methods for max values of machine's usize/isize

We recently wanted this in Miri.

r? @oli-obk
…msg, r=estebank

Link to tracking issue in HIR const-check error code description

This is a follow up to rust-lang#66170 that addresses [this comment](rust-lang#66170 (comment)).

As an aside, the only other error code whose description uses the phrase "tracking issue" is `E0202`. We may want to come up with standards around this, especially since error codes are now centralized and easier to keep track of (thanks @GuillaumeGomez).

r? @estebank (since they +1'ed the comment)
Don't warn labels beginning with `_` on unused_labels lint

Fixes rust-lang#66382

r? @varkor
…=GuillaumeGomez

Cleanup unused function

The argument was not used.

r? @GuillaumeGomez
@JohnTitor
Copy link
Member Author

@bors r+ p=12 rollup=never

@bors
Copy link
Contributor

bors commented Nov 15, 2019

📌 Commit a173353 has been approved by JohnTitor

@bors bors added the S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. label Nov 15, 2019
@bors
Copy link
Contributor

bors commented Nov 15, 2019

⌛ Testing commit a173353 with merge ce36ab2...

@JohnTitor JohnTitor added the rollup A PR which is a rollup label Nov 15, 2019
bors added a commit that referenced this pull request Nov 15, 2019
Rollup of 12 pull requests

Successful merges:

 - #65557 (rename Error::iter_chain() and remove Error::iter_sources())
 - #66013 (Avoid hashing the key twice in `get_query()`.)
 - #66306 (Remove cannot mutate statics in initializer of another static error)
 - #66338 (Update mdbook.)
 - #66388 (Do not ICE on recovery from unmet associated type bound obligation)
 - #66390 (Fix ICE when trying to suggest `Type<>` instead of `Type()`)
 - #66391 (Do not ICE in `if` without `else` in `async fn`)
 - #66398 (Remove some stack frames from `.async` calls)
 - #66410 (miri: helper methods for max values of machine's usize/isize)
 - #66418 (Link to tracking issue in HIR const-check error code description)
 - #66419 (Don't warn labels beginning with `_` on unused_labels lint)
 - #66428 (Cleanup unused function)

Failed merges:

r? @ghost
@bors
Copy link
Contributor

bors commented Nov 15, 2019

☀️ Test successful - checks-azure
Approved by: JohnTitor
Pushing ce36ab2 to master...

@bors bors added the merged-by-bors This PR was explicitly merged by bors. label Nov 15, 2019
@bors bors merged commit a173353 into rust-lang:master Nov 15, 2019
@JohnTitor JohnTitor deleted the rollup-qpv3wia branch November 15, 2019 13:13
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
merged-by-bors This PR was explicitly merged by bors. rollup A PR which is a rollup S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion.
Projects
None yet
Development

Successfully merging this pull request may close these issues.