bors [Sun, 17 Jan 2016 08:40:01 +0000 (08:40 +0000)]
Auto merge of #30928 - sfackler:any-unsized, r=aturon
This is a bit weird since unsized types can't be used in trait objects,
but Any is *also* used as pure marker trait since Reflect isn't stable.
There are many cases (e.g. TypeMap) where all you need is a TypeId.
bors [Sun, 17 Jan 2016 06:47:55 +0000 (06:47 +0000)]
Auto merge of #30426 - gereeter:btree-rewrite, r=Gankro
Despite being over 700 lines shorter, this implementation should use less memory than the previous one and is faster on at least insertions and iteration, the latter improving approximately 5x.
Technically a [breaking-change] due to removal of deprecated functions.
bors [Sat, 16 Jan 2016 16:03:22 +0000 (16:03 +0000)]
Auto merge of #30533 - nikomatsakis:fulfillment-tree, r=aturon
This PR introduces an `ObligationForest` data structure that the fulfillment context can use to track what's going on, instead of the current flat vector. This enables a number of improvements:
1. transactional support, at least for pushing new obligations
2. remove the "errors will be reported" hack -- instead, we only add types to the global cache once their entire subtree has been proven safe. Before, we never knew when this point was reached because we didn't track the subtree.
- this in turn allows us to limit coinductive reasoning to structural traits, which sidesteps #29859
3. keeping the backtrace should allow for an improved error message, where we give the user full context
- we can also remove chained obligation causes
This PR is not 100% complete. In particular:
- [x] Currently, types that embed themselves like `struct Foo { f: Foo }` give an overflow when evaluating whether `Foo: Sized`. This is not a very user-friendly error message, and this is a common beginner error. I plan to special-case this scenario, I think.
- [x] I should do some perf. measurements. (Update: 2% regression.)
- [x] More tests targeting #29859
- [ ] The transactional support is not fully integrated, though that should be easy enough.
- [ ] The error messages are not taking advantage of the backtrace.
I'd certainly like to do 1 through 3 before landing, but 4 and 5 could come as separate PRs.
r? @aturon // good way to learn more about this part of the trait system
f? @arielb1 // already knows this part of the trait system :)
Niko Matsakis [Sat, 9 Jan 2016 02:41:37 +0000 (21:41 -0500)]
Detect cycles and specialize error reporting for Sized. It is important
to get the `Sized` error usable, since that hits new users
frequently. Further work is needed for the error reporting for non-Sized
cycle cases; those currently just fallback to the old path. Also adjust tests.
bors [Sat, 16 Jan 2016 08:20:31 +0000 (08:20 +0000)]
Auto merge of #30930 - oli-obk:fix/30887, r=arielb1
this makes sure the checks run before typeck (which might use the constant or const
function to calculate an array length) and gives prettier error messages in case of for
loops and such (since they aren't expanded yet).
bors [Sat, 16 Jan 2016 05:04:44 +0000 (05:04 +0000)]
Auto merge of #30908 - petrochenkov:backtrace, r=alexcrichton
@dhuseby @semarie Please, confirm that all Rust-specific changes in the second commit are still required.
(It would be ideal to have an unpatched copy of libbacktrace straight from the gcc repo.)
bors [Sat, 16 Jan 2016 01:18:48 +0000 (01:18 +0000)]
Auto merge of #30740 - bluss:ascii-is-the-best, r=brson
Add fast path for ASCII in UTF-8 validation
This speeds up the ASCII case (and long stretches of ASCII in otherwise
mixed UTF-8 data) when checking UTF-8 validity.
Benchmark results suggest that on purely ASCII input, we can improve
throughput (megabytes verified / second) by a factor of 13 to 14 (smallish input).
On XML and mostly English language input (en.wikipedia XML dump),
throughput improves by a factor 7 (large input).
On mostly non-ASCII input, performance increases slightly or is the
same.
The UTF-8 validation is rewritten to use indexed access; since all
access is preceded by a (mandatory for validation) length check, bounds
checks are statically elided by LLVM and this formulation is in fact the best
for performance. A previous version had losses due to slice to iterator
conversions.
A large credit to Björn Steinbrink who improved this patch immensely,
writing this second version.
Benchmark results on x86-64 (Sandy Bridge) compiled with -C opt-level=3.
Old code is `regular`, this PR is called `fast`.
Datasets:
- `ascii` is just ASCII (2.5 kB)
- `cyr` is cyrillic script with ascii spaces (5 kB)
- `dewik10` is 10MB of a de.wikipedia XML dump
- `enwik8` is 100MB of an en.wikipedia XML dump
- `jawik10` is 10MB of a ja.wikipedia XML dump
bors [Fri, 15 Jan 2016 23:26:38 +0000 (23:26 +0000)]
Auto merge of #30878 - brson:raw-pointer-derive, r=brson
This adds back the raw_pointer_derive lint as a 'removed' lint, so that its removal does not cause errors (#30346) but warnings.
In the process I discovered regressions in the code for renamed and removed lints, which didn't appear to have any tests. The addition of a second lint pass (ast vs. hir) meant that attributes were being inspected twice, renamed and removed warnings printed twice. I restructured the code so these tests are only done once and added tests. Unfortunately it makes the patch more complicated for the needed beta backport.
bors [Fri, 15 Jan 2016 21:33:58 +0000 (21:33 +0000)]
Auto merge of #30446 - michaelwu:associated-const-type-params-pt1, r=nikomatsakis
This provides limited support for using associated consts on type parameters. It generally works on things that can be figured out at trans time. This doesn't work for array lengths or match arms. I have another patch to make it work in const expressions.
bors [Fri, 15 Jan 2016 19:44:33 +0000 (19:44 +0000)]
Auto merge of #30890 - nagisa:mir-tuple-adts, r=nikomatsakis
This PR changes translation of tuple-like ADTs from being calls to being proper aggregates. This change is done in hope to make code generation better. Namely, now we can avoid:
1. Call overhead;
2. Generating landingpads in presence of cleanups (we know for sure constructing ADTs can’t panic);
3. And probably much more, gaining better MIR introspectablilty.
Along with that a few serious deficiencies with translation of ADTs and switches have been fixed as well (commits 2 and 3).
bors [Fri, 15 Jan 2016 17:31:08 +0000 (17:31 +0000)]
Auto merge of #30773 - fhahn:test-fix, r=alexcrichton
In my PR for #21659 I accidentally used `// | help` as test annotation. This PR updates it to `//~| help`. I also found and updated 2 other tests with the same issue.
Not merged:
https://github.com/rust-lang/rust/commit/d4fc3ec208186f0a9de8d05a6802c95b07e058fd
@Diggsey says this change was unintended (https://github.com/rust-lang/rust/pull/30666#issuecomment-168616892)
Previously we would generate regular calls for these, which is likely to result in worse LLVM code,
especially in presence of cleanups – we needn’t unecessarilly generate landing pads to construct an
ADT!
Oliver Schneider [Fri, 15 Jan 2016 12:16:54 +0000 (13:16 +0100)]
move const block checks before lowering step
this makes sure the checks run before typeck (which might use the constant or const
function to calculate an array length) and gives prettier error messages in case of for
loops and such (since they aren't expanded yet).
This commit should suffice to add a concise introduction to the concept of crates.
My only worry, is that it is maybe too concise; but, the book seems to be written with the understanding that the new Rust user is coming from another language, and so will understand what a Library or Code Package is.
Rollup merge of #30787 - nikomatsakis:future-incompatible-lint, r=brson
There is now more structure to the report, so that you can specify e.g. an RFC/PR/issue number and other explanatory details.
Example message:
```
type-parameter-invalid-lint.rs:14:8: 14:9 error: defaults for type parameters are only allowed on type definitions, like `struct` or `enum`
type-parameter-invalid-lint.rs:14 fn avg<T=i32>(_: T) {}
^
type-parameter-invalid-lint.rs:14:8: 14:9 warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
type-parameter-invalid-lint.rs:14:8: 14:9 note: for more information, see PR 30742 <https://github.com/rust-lang/rust/pull/30724>
type-parameter-invalid-lint.rs:11:9: 11:28 note: lint level defined here
type-parameter-invalid-lint.rs:11 #![deny(future_incompatible)]
^~~~~~~~~~~~~~~~~~~
error: aborting due to previous error
```
r? @brson
I would really like feedback also on the specific messages!
Steven Fackler [Fri, 15 Jan 2016 07:02:32 +0000 (23:02 -0800)]
Implement Any for unsized types
This is a bit weird since unsized types can't be used in trait objects,
but Any is *also* used as pure marker trait since Reflect isn't stable.
There are many cases (e.g. TypeMap) where all you need is a TypeId.
bors [Fri, 15 Jan 2016 06:38:26 +0000 (06:38 +0000)]
Auto merge of #30763 - gchp:issue/30033, r=nagisa
This is achieved by adding the scan_back method. This method looks back
through the source_text of the StringReader until it finds the target
char, returning it's offset in the source. We use this method to find
the offset of the opening single quote, and use that offset as the start
of the error.
Given this code:
```rust
fn main() {
let _ = 'abcd';
}
```
The compiler would give a message like:
```
error: character literal may only contain one codepoint: ';
let _ = 'abcd';
^~
```
With this change, the message now displays:
```
error: character literal may only contain one codepoint: 'abcd';
let _ = 'abcd';
^~~~~~~
```
Nick Cameron [Wed, 6 Jan 2016 20:23:01 +0000 (09:23 +1300)]
Address reviewer comments
[breaking-change]
`OptLevel` variants are no longer `pub use`ed by rust::session::config. If you are using these variants, you must change your code to prefix the variant name with `OptLevel`.
Nick Cameron [Thu, 31 Dec 2015 05:47:14 +0000 (18:47 +1300)]
Implement JSON error emission
[breaking-change]
syntax::errors::Handler::new has been renamed to with_tty_emitter
Many functions which used to take a syntax::errors::ColorConfig, now take a rustc::session::config::ErrorOutputType. If you previously used ColorConfig::Auto as a default, you should now use ErrorOutputType::default().
Steve Klabnik [Thu, 14 Jan 2016 19:58:34 +0000 (14:58 -0500)]
Rollup merge of #30903 - steveklabnik:no_std_stable, r=alexcrichton
This feature is partially stabilized, so describe each part in the appropriate place.
r? @alexcrichton @brson
It would be nice to backport this to beta, since this is the first release where this is true. I try really hard to not do doc backports, but this isn't very large, and might be worth making an exception, I dunno.
Niko Matsakis [Wed, 23 Dec 2015 00:44:01 +0000 (19:44 -0500)]
switch the fulfillment context to use the new obligation forest;
this commit won't build because, as of this version, no coinductive
reasoning at all is really supported
Niko Matsakis [Thu, 26 Nov 2015 11:46:00 +0000 (06:46 -0500)]
modify trait checker to track the variables on which trait resolution is
stalled rather than keeping this annoying mark; I checked that the
original compile-time regression that the mark was intended to
fix (https://github.com/rust-lang/rust/issues/18208) was still
reasonable, but I've not done exhaustive measurements to see how
important this "optimization" really is anymore