bump mipsel isa leval and enable fpxx
This PR:
* Bumps the default ISA level of the mipsel targets to `mips32r2`. The big endian mips targets are already built with `mips32r2`. This is the usual baseline for the MIPS ISA these days used by other projects, although it does drop support for the 4K processor (which was the only processor released with mips32 r1). Debian no longer supports pre-R2 processors. Using R2 also improves code generation in FPXX in certain circumstances.
* Enables the FPXX floating point ABI[1] on 32-bit hard-float targets by default. This ABI adds some extra restrictions to the existing ABI which allows code to run on the two main floating point modes found on MIPS (FR0 and FR1) and remains compatible with the FR32 ABI currently in use. All code within an executable (including all shared libraries) must be compiled with FPXX/FP64 to be able to use MSA on 32-bit MIPS.
* Enables the "nooddspreg" feature with FPXX. This feature is usually enabled whenever FPXX is. It also helps workaround some issues on Loongson processors. I'm hoping this will fix some test failures mentioned in #39013.
* Adds the `fp64` feature to the MIPS whitelist. This feature must be enabled to use MSA on 32-bit MIPS, otherwise LLVM will complain.
[1] See https://dmz-portal.mips.com/wiki/MIPS_O32_ABI_-_FR0_and_FR1_Interlinking
rustc: Don't invoke `lld` with an `@`-file
Looks like LLD doesn't support this yet, so always try to use the OS before we
fall back to using `@`
cc https://github.com/rust-lang/rust/issues/48948
tweak code fences in the rustdoc book
You can stack backticks to create "big code fences" if you're documenting some markdown and need to have code fences inside your code fences. This is especially important in this spot in the Rustdoc Book, because we're showing that using no language specifier on your code blocks is interpreted as using `rust`, but the code blocks here lose their code fences!
`````````markdown
``````markdown
Just showing some recursion, nbd.
```rust
println!("sup");
```
``````
(If you have edit powers in the rust-lang/rust repo, hit the edit button to view the source and see even more recursion :P)
`````````
Remove some unnecessary IdxSet methods
This replaces `IdxSet:: reset_to_empty` with `IdxSet:: clear`, and `IdxSet::elems`/`IdxSet::each_bit` with `IdxSet::iter`. Based on some [comments on #rustc](https://botbot.me/mozilla/rustc/2018-01-23/?msg=96063396).
r? @pnkfelix
Add info message for -Wall command
Users coming from other languages (namely C and C++) often expect
to use a -Wall flag. Rustc doesn't support that, and previously it
simply printed that it didn't recognize the "all" lint.
This change makes rustc print out a help message, explaining:
- Why there is no -Wall flag
- How to view all the available warnings
- Point out that the most commonly used warning is -Wunused
- Instead of using a command-line flag, the user should consider
a !#[warn(unused)] directive in the root of their crate.
I tried to keep the language consistent with the other usage help. Comment if I should change anything.
closes#10234, if accepted.
Remove syntax and syntax_pos thread locals
This moves `syntax` and `syntax_pos` globals into a struct which are pointed to by thread locals. Most of the changes here are indentation changes in test. It would probably be a good idea to ignore whitespace changes while reviewing. Some indentation is unchanged to avoid merge conflicts.
r? @michaelwoerister
Replace feature(never_type) with feature(exhaustive_patterns).
feature(exhaustive_patterns) only covers the pattern-exhaustives checks
that used to be covered by feature(never_type)
Move ascii::escape_default to libcore
As requested in #46409, the `ascii::escape_default` method has been added to the core library. All I did was copy over the `std::ascii` module file, remove the (redundant) `AsciiExt` trait, and change some of the documentation to match. None of the tests were changed.
I wasn't sure how to handle the annotations. For `EscapeDefault` and `escape_default()`, I changed them to `#[unstable(feature = "core_ascii", issue = "46409")]`. Is that alright? Or should I leave them as they were?
introduce canonical queries, use for normalization and dropck-outlives
This branch adds in the concept of a **canonicalized trait query** and uses it for three specific operations:
- `infcx.at(cause, param_env).normalize(type_foldable)`
- normalizes all associated types in `type_foldable`
- `tcx.normalize_erasing_regions(param_env, type_foldable)`
- like normalize, but erases regions first and in the result; this leads to better caching
- `infcx.at(cause, param_env).dropck_outlives(ty)`
- produces the set of types that must be live when a value of type `ty` is dropped
- used from dropck but also NLL outlives
This is a kind of "first step" towards a more Chalk-ified approach. It leads to a **big** speedup for NLL, which is basically dominated by the dropck-outlives computation. Here are some timing measurements for the `syn` crate (pre-branch measurements coming soon):
| Commit | NLL disabled | NLL enabled |
| ------- | --- | --- |
| Before my branch | 5.43s | 8.99s |
| After my branch | 5.36s | 7.25s |
(Note that NLL enabled still does *all the work* that NLL disabled does, so this is not really a way to compare the performance of NLL versus the AST-based borrow checker directly.) Since this affects all codepaths, I'd like to do a full perf run before we land anything.
Also, this is not the "final point" for canonicalization etc. I think canonicalization can be made substantially faster, for one thing. But it seems like a reasonable starting point for a branch that's gotten a bit larger than I would have liked.
**Commit convention:** First of all, this entire branch ought to be a "pure refactoring", I believe, not changing anything about external behavior. Second, I've tagged the most important commits with `[VIC]` (very important commit), so you can scan for those. =)
r? @eddyb
