Suggest more helpful formatting string
Based on [user feedback](https://users.rust-lang.org/t/ux-feedback-from-a-rust-newbie/17220) the minimal suggestion of `:?` is unclear.
Also `{:#?}` is much more readable than the standard debug, so this PR suggests it to help surface this nice feature.
In particular, type annotations given by the user must hold at all
points in the program. This doesn't affect current analysis but
will affect fact generation later.
Avoid many `cmt` allocations.
`cmt` is a ref-counted wrapper around `cmt_` The use of refcounting
keeps `cmt` handling simple, but a lot of `cmt` instances are very
short-lived, and heap-allocating the short-lived ones takes up time.
This patch changes things in the following ways.
- Most of the functions that produced `cmt` instances now produce `cmt_`
instances. The `Rc::new` calls that occurred within those functions
now occur at their call sites (but only when necessary, which isn't
that often).
- Many of the functions that took `cmt` arguments now take `&cmt_`
arguments. This includes all the methods in the `Delegate` trait.
As a result, the vast majority of the heap allocations are avoided. In
an extreme case, the number of calls to malloc in tuple-stress drops
from 9.9M to 7.9M, a drop of 20%. And the compile times for many runs of
coercions, deep-vector, and tuple-stress drop by 1--2%.
Add armv5te-unknown-linux-musl target
This PR adds the armv5te-unknown-linux-musl target. The following steps should let you produce a fully statically linked binary now:
1. Running `./src/ci/docker/run.sh dist-armv5te-linux-musl`
2. Changing the run.sh script to start bash instead of the build process and running the container
3.
```sh
export USER=root
export PATH=/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin:/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin:$PATH
```
4. Configuring Cargo
```yaml
[target.armv5te-unknown-linux-musl]
linker = "arm-linux-gnueabi-gcc"
```
5. Building a project
```sh
cargo new --bin hello
cd hello
cargo build --target=armv5te-unknown-linux-musl --release
```
rustdoc: Resolve nested `impl Trait`s
Fixes#50358.
Populates `cx.impl_trait_bounds` incrementally while `clean`ing generic params, so that a synthetic type-parameter can refer to previous ones.
cc #50366
First step towards rustfix compiletest mode
This is the first small step towards testing auto-fixable compiler
suggestions using compiletest. Currently, it only checks if next to a
UI test there also happens to a `*.rs.fixed` file, and then uses rustfix
(added as external crate) on the original file, and asserts that it
produces the fixed version.
To show that this works, I've included one such test. I picked this test
case at random (and because it was simple) -- It is not relevant to the
2018 edition. Indeed, in the near future, we want to be able to restrict
rustfix to edition-lints, so this test cast might go away soon.
In case you still think this is somewhat feature-complete, here's a
quick list of things currently missing that I want to add before telling
people they can use this:
- [x] Make this an actual compiletest mode, with `test [fix] …` output
and everything
- [x] Assert that fixed files still compile
- [x] Assert that fixed files produce no (or a known set of) diagnostics
output
- [x] Update `update-references.sh` to support rustfix
- [x] Use a published version of rustfix (i.e.: publish a new version
rustfix that exposes a useful API for this)
This commit adds a dedicated mode to compiletest for running rustfix tests,
adding a new `src/test/rustfix` directory which will execute all tests as a
"rustfix" test, namely requiring that a `*.fixed` is next to the main file which
is the result of the rustfix project's application of fixes.
The `rustfix` crate is pulled in to actually perform the fixing, and the rustfix
compiletest mode will assert a few properties about the fixing:
* The expected fixed output must be the same as rustc's output suggestions
applied to the original code.
* The fixed code must compile successfully
* The fixed code must have no further diagnostics emitted about it
This is the first small step towards testing auto-fixable compiler
suggestions using compiletest. Currently, it only checks if next to a
UI test there also happens to a `*.rs.fixed` file, and then uses rustfix
(added as external crate) on the original file, and asserts that it
produces the fixed version.
To show that this works, I've included one such test. I picked this test
case at random (and because it was simple) -- It is not relevant to the
2018 edition. Indeed, in the near future, we want to be able to restrict
rustfix to edition-lints, so this test cast might go away soon.
In case you still think this is somewhat feature-complete, here's a
quick list of things currently missing that I want to add before telling
people they can use this:
- [ ] Make this an actual compiletest mode, with `test [fix] …` output
and everything
- [ ] Assert that fixed files still compile
- [ ] Assert that fixed files produce no (or a known set of) diagnostics
output
- [ ] Update `update-references.sh` to support rustfix
- [ ] Use a published version of rustfix (i.e.: publish a new version
rustfix that exposes a useful API for this)
This commit adds explicit imp blocks to ensure that all publicly exported types
(except simple enums) are not `Send` nor `Sync` in the `proc_macro` crate.
cc #38356
Immutably and implicitly borrow all pattern ids for their guards (NLL only)
This is an important piece of rust-lang/rust#27282.
It applies only to NLL mode. It is a change to MIR codegen that is currently toggled on only when NLL is turned on. It thus affect MIR-borrowck but not the earlier static analyses (such as the type checker).
This change makes it so that any pattern bindings of type T for a match arm will map to a `&T` within the context of the guard expression for that arm, but will continue to map to a `T` in the context of the arm body.
To avoid surfacing this type distinction in the user source code (which would be a severe change to the language and would also require far more revision to the compiler internals), any occurrence of such an identifier in the guard expression will automatically get a deref op applied to it.
So an input like:
```rust
let place = (1, Foo::new());
match place {
(1, foo) if inspect(foo) => feed(foo),
...
}
```
will be treated as if it were really something like:
```rust
let place = (1, Foo::new());
match place {
(1, Foo { .. }) if { let tmp1 = &place.1; inspect(*tmp1) }
=> { let tmp2 = place.1; feed(tmp2) },
...
}
```
And an input like:
```rust
let place = (2, Foo::new());
match place {
(2, ref mut foo) if inspect(foo) => feed(foo),
...
}
```
will be treated as if it were really something like:
```rust
let place = (2, Foo::new());
match place {
(2, Foo { .. }) if { let tmp1 = & &mut place.1; inspect(*tmp1) }
=> { let tmp2 = &mut place.1; feed(tmp2) },
...
}
```
In short, any pattern binding will always look like *some* kind of `&T` within the guard at least in terms of how the MIR-borrowck views it, and this will ensure that guard expressions cannot mutate their the match inputs via such bindings. (It also ensures that guard expressions can at most *copy* values from such bindings; non-Copy things cannot be moved via these pattern bindings in guard expressions, since one cannot move out of a `&T`.)
Remove the deprecated std::net::{lookup_host,LookupHost}
These are unstable, and were deprecated by #47510, since Rust 1.25. The
internal `sys` implementations are still kept to support the call in the
common `resolve_socket_addr`.
nano-optimization for memchr::repeat_byte
This replaces the multiple shifts & bitwise or with a single multiplication
In my benchmarks this performs equally well or better, especially on 64bit systems (it shaves a stable nanosecond on my skylake). This may go against conventional wisdom, but the shifts and bitwise ors cannot be pipelined because of hard data dependencies.
While it may or may not be worthwile from an optimization standpoint, it also reduces code size, so there's basically no downside.
Update RLS and Rustfmt (and Cargo)
Updates RLS and Rustfmt (the latter fixing tests). Cargo is updated too (to fix RLS tests), but that is covered by https://github.com/rust-lang/rust/pull/50417, so probably won't do much.
r? @alexcrichton