Auto merge of #77013 - RalfJung:rollup-84ut0xq, r=RalfJung
Rollup of 10 pull requests
Successful merges:
- #76439 (Add error explanation for E0755)
- #76521 (Fix segfault if pthread_getattr_np fails)
- #76835 (make replace_prefix only take &str as arguments )
- #76967 (Revert adding Atomic::from_mut.)
- #76977 (Add a regression test for copy propagation miscompilation)
- #76981 (liballoc bench use imported path Bencher)
- #76983 (BTreeMap: extra testing & fixed comments)
- #76996 (Fix typo in rustc_lexer docs)
- #77009 (Dogfood total_cmp in the test crate)
- #77012 (update Miri for another bugfix)
Rollup merge of #76521 - tavianator:fix-pthread-getattr-destroy, r=Amanieu
Fix segfault if pthread_getattr_np fails
glibc [destroys][1] the passed pthread_attr_t if pthread_getattr_np()
fails. Destroying it again leads to a segfault. Fix it by only
destroying it on success for glibc.
This PR tries to move the sound `&mut UnsafeCell<T> -> &mut T` projection that all the "downstream" constructions were already relying on, up to the root abstraction, where it rightfully belongs, and officially blessing it.
- this **helps reduce the amount of `unsafe` snippets out there** (_c.f._, the second commit of this PR: https://github.com/rust-lang/rust/pull/76936/commits/09503fd1b30c83ca605546fa3f899721e41e68c6)
The fact that this getter is now expose for `UnsafeCell<T>` itself, will also help convey the idea that **`UnsafeCell` is not magical _w.r.t._ `&mut` accesses**, contrary to what some people incorrectly think.
- Even the standard library itself at some point had such a confusion, _c.f._ this comment where there is a mention of multi-threaded (and thus _shared_) access despite dealing with exclusive references over unique ownership: https://github.com/rust-lang/rust/blob/59fb88d061544a035f3043b47594b34789204cee/library/core/src/cell.rs#L498-L499
Rollup merge of #76872 - khyperia:remove_declare_methods, r=eddyb
Remove DeclareMethods
Most of the `DeclareMethods` API was only used internally by rustc_codegen_llvm. As such, it makes no sense to require other backends to implement them.
(`get_declared_value` and `declare_cfn` were used, in one place, specific to the `main` symbol, which I've replaced with a more specialized function to allow more flexibility in implementation - the intent is that `declare_c_main` can go away once we do something more clever, e.g. @eddyb has ideas around having a MIR shim or somesuch we can explore in a follow-up PR)
Rollup merge of #76628 - jyn514:default-config-files, r=Mark-Simulacrum
Add sample defaults for config.toml
- Allow including defaults in `src/bootstrap/defaults` using `profile = "..."`.
- Add default config files, with a README noting they're experimental and asking you to open an issue if you run into trouble. The config files have comments explaining why the defaults are set.
- Combine config files using the `merge` dependency.
This introduces a new dependency on `merge` that hasn't yet been vetted.
I want to improve the output when `include = "x"` isn't found:
```
thread 'main' panicked at 'fs::read_to_string(&file) failed with No such file or directory (os error 2) ("configuration file did not exist")', src/bootstrap/config.rs:522:28
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failed to run: /home/joshua/rustc/build/bootstrap/debug/bootstrap test tidy
Build completed unsuccessfully in 0:00:00
```
However that seems like it could be fixed in a follow-up.
Rollup merge of #76135 - CDirkx:const-option, r=dtolnay,oli-obk
Stabilize some Option methods as const
Stabilize the following methods of `Option` as const:
- `is_some`
- `is_none`
- `as_ref`
These methods are currently const under the unstable feature `const_option` (tracking issue: #67441).
I believe these methods to be eligible for stabilization because of the stabilization of #49146 (Allow if and match in constants) and the trivial implementations, see also: [PR#75463](https://github.com/rust-lang/rust/pull/75463).
Auto merge of #76843 - kornelski:longtypetofile, r=ecstatic-morse
Let user see the full type of type-length limit error
Seeing the full type of the error is sometimes essential to diagnosing the problem, but the type itself is too long to be displayed in the terminal in a useful fashion. This change solves this dilemma by writing the full offending type name to a file, and displays this filename as a note.
> note: the full type name been written to '$TEST_BUILD_DIR/issues/issue-22638/issue-22638.long-type.txt'
Auto merge of #75974 - SkiFire13:peekmut-opt-sift, r=LukasKalbertodt
Avoid useless sift_down when std::collections::binary_heap::PeekMut is never mutably dereferenced
If `deref_mut` is never called then it's not possible for the element to be mutated without internal mutability, meaning there's no need to call `sift_down`.
This could be a little improvement in cases where you want to mutate the biggest element of the heap only if it satisfies a certain predicate that needs only read access to the element.
Auto merge of #76295 - mati865:remove-mmx, r=Amanieu,oli-obk
Remove MMX from Rust
Follow-up to https://github.com/rust-lang/stdarch/pull/890
This removes most of MMX from Rust (tests pass with small changes), keeping stable `is_x86_feature_detected!("mmx")` working.
Auto merge of #76544 - Mark-Simulacrum:less-python, r=alexcrichton
De-couple Python and bootstrap slightly
This revises rustbuild's entry points from Python to rely less on magic environment variables, preferring to use Cargo-provided environment variables where feasible.
Notably, BUILD_DIR and BOOTSTRAP_CONFIG are *not* moved, because both more-or-less have some non-trivial discovery logic and replicating it in rustbuild seems unfortunate; if it moved to Cargo that would be a different story.
Joshua Nelson [Sat, 12 Sep 2020 04:42:52 +0000 (00:42 -0400)]
Add sample defaults for config.toml
- Allow including defaults in `src/bootstrap/defaults` using `profile = "..."`
- Add default config files
- Combine config files using the merge dependency.
- Add comments to default config files
- Add a README asking to open an issue if the defaults are bad
- Give a loud error if trying to merge `.target`, since it's not
currently supported
- Use an exhaustive match
- Use `<none>` in config.toml.example to avoid confusion
- Fix bugs in `Merge` derives
Previously, it would completely ignore the profile defaults if there
were any settings in `config.toml`. I sent an email to the `merge` maintainer
asking them to make the behavior in this commit the default.
This introduces a new dependency on `merge` that hasn't yet been vetted.
I want to improve the output when `include = "x"` isn't found:
```
thread 'main' panicked at 'fs::read_to_string(&file) failed with No such file or directory (os error 2) ("configuration file did not exist")', src/bootstrap/config.rs:522:28
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failed to run: /home/joshua/rustc/build/bootstrap/debug/bootstrap test tidy
Build completed unsuccessfully in 0:00:00
```
However that seems like it could be fixed in a follow-up.
Mark Rousskov [Mon, 7 Sep 2020 01:32:55 +0000 (21:32 -0400)]
Remove support for different src directory
This requires that bootstrap is run from the same worktree as the sources it'll
build, but this is basically required for the build to work anyway. You can
still run it from a different directory, just that the files it builds must be
beside it.
Mark Rousskov [Sun, 6 Sep 2020 23:57:07 +0000 (19:57 -0400)]
Set BUILD_TRIPLE via build script
This moves build triple discovery for rustbuild from bootstrap.py into a build
script, meaning it will "just work" if building rustbuild via Cargo rather than
Python.
Auto merge of #75119 - simonvandel:early-otherwise, r=oli-obk
New MIR optimization pass to reduce branches on match of tuples of enums
Fixes #68867 by adding a new pass that turns something like
```rust
let x: Option<()>;
let y: Option<()>;
match (x,y) {
(Some(_), Some(_)) => {0},
_ => {1}
}
```
into something like
```rust
let x: Option<()>;
let y: Option<()>;
let discriminant_x = // get discriminant of x
let discriminant_y = // get discriminant of x
if discriminant_x != discriminant_y {1} else {0}
```
The opt-diffs still have the old basic blocks like
```
bb3: {
_8 = discriminant((*(_4.1: &ViewportPercentageLength))); // scope 0 at $DIR/early-otherwise-branch-68867.rs:21:21: 21:30
switchInt(move _8) -> [1_isize: bb7, otherwise: bb2]; // scope 0 at $DIR/early-otherwise-branch-68867.rs:21:21: 21:30
}
Auto merge of #76975 - RalfJung:rollup-s2wiuqr, r=RalfJung
Rollup of 15 pull requests
Successful merges:
- #76732 (Add docs for `BasicBlock`)
- #76832 (Let backends define custom targets)
- #76866 (Remove unused feature gates from library/ crates)
- #76875 (Move to intra-doc links in library/alloc/src/collections/binary_heap.rs)
- #76876 (Move to intra-doc links in collections/btree/map.rs and collections/linked_list.rs)
- #76877 (Move to intra-doc links in collections/vec_deque.rs and collections/vec_deque/drain.rs)
- #76878 (Move the version number to a plaintext file)
- #76883 (README.md: Remove prompts from code blocks)
- #76887 (Add missing examples on HashSet iter types)
- #76890 (use matches!() macro for simple if let conditions)
- #76891 (don't take `TyCtxt` by reference)
- #76910 (transmute: use diagnostic item)
- #76924 (Add tracking issue for feature(unix_socket_peek))
- #76926 (BTreeMap: code readability tweaks)
- #76940 (Don't allow implementing trait directly on type-alias-impl-trait)
Rollup merge of #76878 - pietroalbini:version, r=Mark-Simulacrum
Move the version number to a plaintext file
The Rust version number is currently embedded in bootstrap's source code, which makes it hard to update it automatically or access it outside of ./x.py (as you'd have to parse the source code).
This PR moves the version number to a standalone plaintext file, which makes accessing or updating it trivial.
Removes some unused feature gates from library crates. It's likely not a complete list as I only tested a subset for which it's more likely that it is unused.
Auto merge of #76136 - CDirkx:const-result, r=dtolnay
Stabilize some Result methods as const
Stabilize the following methods of Result as const:
- `is_ok`
- `is_err`
- `as_ref`
A test is also included, analogous to the test for `const_option`.
These methods are currently const under the unstable feature `const_result` (tracking issue: #67520).
I believe these methods to be eligible for stabilization because of the stabilization of #49146 (Allow if and match in constants) and the trivial implementations, see also: [PR#75463](https://github.com/rust-lang/rust/pull/75463) and [PR#76135](https://github.com/rust-lang/rust/pull/76135).
Note: these methods are the only methods currently under the `const_result` feature, thus this PR results in the removal of the feature.
Auto merge of #76964 - RalfJung:rollup-ybn06fs, r=RalfJung
Rollup of 15 pull requests
Successful merges:
- #76722 (Test and fix Send and Sync traits of BTreeMap artefacts)
- #76766 (Extract some intrinsics out of rustc_codegen_llvm)
- #76800 (Don't generate bootstrap usage unless it's needed)
- #76809 (simplfy condition in ItemLowerer::with_trait_impl_ref())
- #76815 (Fix wording in mir doc)
- #76818 (Don't compile regex at every function call.)
- #76821 (Remove redundant nightly features)
- #76823 (black_box: silence unused_mut warning when building with cfg(miri))
- #76825 (use `array_windows` instead of `windows` in the compiler)
- #76827 (fix array_windows docs)
- #76828 (use strip_prefix over starts_with and manual slicing based on pattern length (clippy::manual_strip))
- #76840 (Move to intra doc links in core/src/future)
- #76845 (Use intra docs links in core::{ascii, option, str, pattern, hash::map})
- #76853 (Use intra-doc links in library/core/src/task/wake.rs)
- #76871 (support panic=abort in Miri)
Rollup merge of #76871 - RalfJung:miri-panic-abort, r=dtolnay
support panic=abort in Miri
This is needed for https://github.com/rust-lang/miri/issues/1058 on Windows: we cannot run the inline-assembly versions of `abort`, so fall back to the intrinsic (which Miri supports).
Rollup merge of #76825 - lcnr:array-windows-apply, r=varkor
use `array_windows` instead of `windows` in the compiler
I do think these changes are beautiful, but do have to admit that using type inference for the window length
can easily be confusing. This seems like a general issue with const generics, where inferring constants adds an additional
complexity which users have to learn and keep in mind.
Rollup merge of #76821 - est31:remove_redundant_nightly_features, r=oli-obk,Mark-Simulacrum
Remove redundant nightly features
Removes a bunch of redundant/outdated nightly features. The first commit removes a `core_intrinsics` use for which a stable wrapper has been provided since. The second commit replaces the `const_generics` feature with `min_const_generics` which might get stabilized this year. The third commit is the result of a trial/error run of removing every single feature and then adding it back if compile failed. A bunch of unused features are the result that the third commit removes.