Mark Rousskov [Tue, 17 Dec 2019 17:47:10 +0000 (12:47 -0500)]
Disable cargo tests for now
These depend on rustc being bug-free and it looks like that's not
currently entirely the case (e.g., we know of at least one bug that
introduces nondeterminism).
Mark Rousskov [Mon, 16 Dec 2019 21:27:35 +0000 (16:27 -0500)]
Always build and ship parallel-enabled compilers
This also removes the unused NO_PARALLEL_COMPILER flag; if we want that
functionality we can readd it but this makes sure we really are parallel
everywhere.
This also patches a test that has differing output in the parallel case
(hopefully deterministically so!).
Mark Rousskov [Mon, 16 Dec 2019 21:23:07 +0000 (16:23 -0500)]
Change the default thread count to min(4, vCPUs)
This avoids the problems of high thread counts (i.e., contention in the
kernel on the jobserver pipe due to thundering herd of readers) while
stil giving rustc some parallelism to work with.
Rollup merge of #65778 - bdonlan:stable_weak_count, r=dtolnay
Stabilize `std::{rc,sync}::Weak::{weak_count, strong_count}`
* Original PR: #56696
* Tracking issue: #57977
Closes: #57977
Supporting comments:
> Although these were added for testing, it is occasionally useful to have a way to probe optimistically for whether a weak pointer has become dangling, without actually taking the overhead of manipulating atomics. Are there any plans to stabilize this?
_Originally posted by @bdonlan in https://github.com/rust-lang/rust/issues/57977#issuecomment-516970921_
> Having this stabilized would help. Currently, the only way to check if a weak pointer has become dangling is to call `upgrade`, which is by far expensive.
_Originally posted by @glebpom in https://github.com/rust-lang/rust/issues/57977#issuecomment-526934709_
Not sure if stabilizing these warrants a full RFC, so throwing this out here as a start for now.
Note: per CONTRIBUTING.md, I ran the tidy checks, but they seem to be failing on unchanged files (primarily in `src/stdsimd`).
bors [Sun, 15 Dec 2019 07:17:06 +0000 (07:17 +0000)]
Auto merge of #67310 - Centril:rollup-22jiyow, r=Centril
Rollup of 6 pull requests
Successful merges:
- #67255 (Remove i686-unknown-dragonfly target)
- #67267 (Fix signature of `__wasilibc_find_relpath`)
- #67282 (Fix example code of OpenOptions::open)
- #67289 (Do not ICE on unnamed future)
- #67300 (Restore original implementation of Vec::retain)
- #67305 (Doc typo)
Rollup merge of #67300 - aloucks:issue-65970, r=rkruppe
Restore original implementation of Vec::retain
This PR reverts #48065, which aimed to optimize `Vec::retain` by making use of `Vec::drain_filter`. Unfortunately at that time, `drain_filter` was unsound.
The soundness hole in `Vec::drain_filter` was fixed in #61224 by guaranteeing that cleanup logic runs via a nested `Drop`, even in the event of a panic. Implementing this nested drop affects codegen (apparently?) and results in slower code.
bors [Sun, 15 Dec 2019 01:28:28 +0000 (01:28 +0000)]
Auto merge of #67216 - ecstatic-morse:const-loop, r=oli-obk
Enable `loop` and `while` in constants behind a feature flag
This PR is an initial implementation of #52000. It adds a `const_loop` feature gate, which allows `while` and `loop` expressions through both HIR and MIR const-checkers if enabled. `for` expressions remain forbidden by the HIR const-checker, since they desugar to a call to `IntoIterator::into_iter`, which will be rejected anyways.
`while` loops also require [`#![feature(const_if_match)]`](https://github.com/rust-lang/rust/pull/66507), since they have a conditional built into them. The diagnostics from the HIR const checker will suggest this to the user.
I decided to keep the separate `never-type-fallback` feature gate, but tried to otherwise revert https://github.com/rust-lang/rust/pull/65355. Seemed pretty clean.
( cc @Centril, author of #65355, you may want to check this over briefly )
Aaron Loucks [Sat, 14 Dec 2019 17:38:45 +0000 (12:38 -0500)]
Restore original implementation of Vec::retain
This PR reverts #48065, which aimed to optimize `Vec::retain` by
making use of `Vec::drain_filter`. Unfortunately at that time,
`drain_filter` was unsound.
The soundness hole in `Vec::drain_filter` was fixed in #61224 by
guaranteeing that cleanup logic runs via a nested `Drop`, even in
the event of a panic. Implementing this nested drop affects codegen
(apparently?) and results in slower code.
bors [Sat, 14 Dec 2019 10:21:32 +0000 (10:21 +0000)]
Auto merge of #67136 - oli-obk:const_stability, r=Centril
Require stable/unstable annotations for the constness of all stable fns with a const modifier
r? @RalfJung @Centril
Every `#[stable]` const fn now needs either a `#[rustc_const_unstable]` attribute or a `#[rustc_const_stable]` attribute. You can't silently stabilize the constness of a function anymore.
bors [Sat, 14 Dec 2019 04:08:50 +0000 (04:08 +0000)]
Auto merge of #67084 - Pagten:feature/print-msg-from-elf-entrypoint, r=Amanieu
SGX: Change ELF entrypoint
This fixes [rust-sgx issue #148](https://github.com/fortanix/rust-sgx/issues/148).
A new entry point is created for the ELF file generated by `rustc`, separate from the enclave entry point. When the ELF file is executed as a Linux binary, the error message below is written to stderr.
> Error: This file is an SGX enclave which cannot be executed as a standard Linux binary.
> See the installation guide at https://edp.fortanix.com/docs/installation/guide/ on how to use 'cargo run' or follow the steps at https://edp.fortanix.com/docs/tasks/deployment/ for manual deployment.
When the ELF file is converted to an SGXS using `elf2sgxs`, the old entry point is still set as the enclave entry point. In a future pull request in the rust-sgx repository, `elf2sgxs` will be modified to remove the code in the ELF entry point, since this code is not needed in the enclave.
bors [Fri, 13 Dec 2019 19:39:20 +0000 (19:39 +0000)]
Auto merge of #67284 - Centril:rollup-ghiukob, r=Centril
Rollup of 7 pull requests
Successful merges:
- #67026 (Improve diagnostics and code for exhaustiveness of empty matches)
- #67235 (VecDeque: drop remaining items on destructor panic)
- #67254 (dont ICE in case of invalid drop fn)
- #67256 (Reduce allocs for validation errors)
- #67274 (be explicit that mem::uninitialized is the same as MaybeUninit::uninit().assume_init())
- #67278 (`coerce_inner`: use initial `expected_ty`)
- #67280 (docs: std::convert::From: Fix typo)
Rollup merge of #67026 - Nadrieril:improve-usefulness-empty, r=varkor,Centril,estebank
Improve diagnostics and code for exhaustiveness of empty matches
There was a completely separate check and diagnostics for the case of an empty match. This led to slightly different error messages and duplicated code.
This improves code reuse and generally clarifies what happens for empty matches. This also clarifies the action of the `exhaustive_patterns` feature, and ensures that this feature doesn't change diagnostics in places it doesn't need to.
Dylan MacKenzie [Wed, 11 Dec 2019 18:09:10 +0000 (10:09 -0800)]
Look for "unstable feature" error code in test
Conditionals and loops now have unstable features, and `feature_err` has
its own error code. I think that `feature_err` should take an error code
as a parameter, but don't have the energy to make this change throughout
the codebase. Also, the error code system may be torn out entirely.
bors [Fri, 13 Dec 2019 03:22:20 +0000 (03:22 +0000)]
Auto merge of #67271 - Centril:rollup-i71iqkv, r=Centril
Rollup of 6 pull requests
Successful merges:
- #66341 (Match `VecDeque::extend` to `Vec::extend_desugared`)
- #67243 (LinkedList: drop remaining items when drop panics)
- #67247 (Don't suggest wrong snippet in closure)
- #67250 (Remove the `DelimSpan` from `NamedMatch::MatchedSeq`.)
- #67251 (Require `allow_internal_unstable` for stable min_const_fn using unsta…)
- #67269 (parser: recover on `&'lifetime mut? $pat`.)
Rollup merge of #67250 - nnethercote:rm-DelimSpan-from-NamedMatch-MatchedSeq, r=Centril
Remove the `DelimSpan` from `NamedMatch::MatchedSeq`.
Because it's unused. This then allows the removal of
`MatcherPos::sp_open`. It's a tiny perf win, reducing instruction counts
by 0.1% - 0.2% on a few benchmarks.
Rollup merge of #66341 - crgl:vec-deque-extend, r=Amanieu
Match `VecDeque::extend` to `Vec::extend_desugared`
Currently, `VecDeque::extend` [does not reserve at all](https://github.com/rust-lang/rust/pull/65069#discussion_r333166522). This implementation still runs a check every iteration of the loop, but should reallocate at most once for the common cases where the `size_hint` lower bound is exact. Further optimizations in the future could improve this for some common cases, but given the complexity of the `Vec::extend` implementation it's not immediately clear that this would be worthwhile.
In particular, it has bugged me for some time that `process_cycles` is
currently located before `mark_still_waiting_nodes` despite being called
afterwards.
`NodeState` has two states, `Success` and `Done`, that are only used
within `ObligationForest` methods. This commit removes them, and renames
the existing `Waiting` state as `Success`.
We are left with three states: `Pending`, `Success`, and `Error`.
`Success` is augmented with a new `WaitingState`, which indicates when
(if ever) it was last waiting on one or more `Pending` nodes. This
notion of "when" requires adding a "process generation" to
`ObligationForest`; it is incremented on each call to
`process_obligtions`.
This commit is a performance win.
- Most of the benefit comes from `mark_as_waiting` (which the commit
renames as `mark_still_waiting_nodes`). This function used to do two
things: (a) change all `Waiting` nodes to `Success`, and (b) mark all
nodes that depend on a pending node as `Waiting`. In practice, many
nodes went from `Waiting` to `Success` and then immediately back to
`Waiting`. The use of generations lets us skip step (a).
- A smaller benefit comes from not having to change nodes to the `Done`
state in `process_cycles`.