bors [Sat, 19 Dec 2015 02:45:15 +0000 (02:45 +0000)]
Auto merge of #30184 - petrochenkov:ascr, r=nikomatsakis
This PR is a rebase of the original PR by @eddyb https://github.com/rust-lang/rust/pull/21836 with some unrebasable parts manually reapplied, feature gate added + type equality restriction added as described below.
This implementation is partial because the type equality restriction is applied to all type ascription expressions and not only those in lvalue contexts. Thus, all difficulties with detection of these contexts and translation of coercions having effect in runtime are avoided.
So, you can't write things with coercions like `let slice = &[1, 2, 3]: &[u8];`. It obviously makes type ascription less useful than it should be, but it's still much more useful than not having type ascription at all.
In particular, things like `let v = something.iter().collect(): Vec<_>;` and `let u = t.into(): U;` work as expected and I'm pretty happy with these improvements alone.
Part of https://github.com/rust-lang/rust/issues/23416
bors [Fri, 18 Dec 2015 18:54:52 +0000 (18:54 +0000)]
Auto merge of #29973 - petrochenkov:privinpub, r=nikomatsakis
Some notes:
This patch enforces the rules from [RFC 136](https://github.com/rust-lang/rfcs/blob/master/text/0136-no-privates-in-public.md) and makes "private in public" a module-level concept and not crate-level. Only `pub` annotations are used by the new algorithm, crate-level exported node set produced by `EmbargoVisitor` is not used. The error messages are tweaked accordingly and don't use the word "exported" to avoid confusing people (https://github.com/rust-lang/rust/issues/29668).
The old algorithm tried to be extra smart with impls, but it mostly led to unpredictable behavior and bugs like https://github.com/rust-lang/rust/issues/28325.
The new algorithm tries to be as simple as possible - an impl is considered public iff its type is public and its trait is public (if presents).
A type or trait is considered public if all its components are public, [complications](https://internals.rust-lang.org/t/limits-of-type-inference-smartness/2919) with private types leaking to other crates/modules through trait impls and type inference are deliberately ignored so far.
The new algorithm is not recursive and uses the nice new facility `Crate::visit_all_items`!
Obsolete pre-1.0 feature `visible_private_types` is removed.
This is a [breaking-change].
The two main vectors of breakage are type aliases (https://github.com/rust-lang/rust/issues/28450) and impls (https://github.com/rust-lang/rust/issues/28325).
I need some statistics from a crater run (cc @alexcrichton) to decide on the breakage mitigation strategy.
UPDATE: All the new errors are reported as warnings controlled by a lint `private_in_public` and lint group `future_incompatible`, but the intent is to make them hard errors eventually.
Rollup merge of #30452 - dotdash:24876_take_2, r=alexcrichton
LLVM doesn't really support reusing the same module to emit more than
one file. One bug this causes is that the IR is invalidated by the stack
coloring pass when emitting the first file, and then the IR verifier
complains by the time we try to emit the second file. Also, we get
different binaries with --emit=asm,link than with just --emit=link. In
some cases leading to segfaults.
Unfortunately, it seems that at this point in time, the most sensible
option to circumvent this problem is to just clone the whole llvm module
for the asm output if we need both, asm and obj file output.
bors [Fri, 18 Dec 2015 12:23:54 +0000 (12:23 +0000)]
Auto merge of #30286 - oli-obk:const_error_span, r=nikomatsakis
previously the error was erased and a `non-const path` error was emitted at the location of the field access instead of at the overflow location (as can be seen in the playground: http://is.gd/EuAF5F )
Rollup merge of #30406 - durka:patch-13, r=sanxiyn
The previous example had no chance of compiling in either form, due to the restrictive follow set for `ty`. This one has the desired behavior: http://is.gd/kYdw4g (well, I don't exactly desire this behavior at all, but it's true at least :p )
Rollup merge of #30286 - oli-obk:const_error_span, r=nikomatsakis
previously the error was erased and a `non-const path` error was emitted at the location of the field access instead of at the overflow location (as can be seen in the playground: http://is.gd/EuAF5F )
Björn Steinbrink [Fri, 18 Dec 2015 00:24:40 +0000 (01:24 +0100)]
Fix emitting asm and object file output at the same time
LLVM doesn't really support reusing the same module to emit more than
one file. One bug this causes is that the IR is invalidated by the stack
coloring pass when emitting the first file, and then the IR verifier
complains by the time we try to emit the second file. Also, we get
different binaries with --emit=asm,link than with just --emit=link. In
some cases leading to segfaults.
Unfortunately, it seems that at this point in time, the most sensible
option to circumvent this problem is to just clone the whole llvm module
for the asm output if we need both, asm and obj file output.
bors [Fri, 18 Dec 2015 03:05:02 +0000 (03:05 +0000)]
Auto merge of #30414 - alexcrichton:fix-cross-builds, r=brson
It looks like #27937 accidentally switched the llvmdeps file from the target to
the host by accident, so be sure to use the right llvmdeps file which is built
for the target when building rustc_llvm
Steve Klabnik [Thu, 17 Dec 2015 19:47:14 +0000 (14:47 -0500)]
Rollup merge of #30439 - swooster:swooster-nomicon-patch-1, r=steveklabnik
The Rustonomicon's Lifetimes chapter uses the idiom "big ask", which is obscure compared to "tall order" (check [Google ngrams](https://books.google.com/ngrams/graph?content=big+ask%2C+tall+order&year_start=1800)). Also, it's easily mistaken for a typo; either "a big task" or "a big thing to ask" could plausibly work there.
Steve Klabnik [Thu, 17 Dec 2015 19:47:13 +0000 (14:47 -0500)]
Rollup merge of #30404 - Shiney:ImprovedStackHeap, r=steveklabnik
…entation clearer
I could not use colors as suggested for #29854 because Github doesn't support these in markdown, however this solution may be better for color-blind readers.
bors [Thu, 17 Dec 2015 18:21:25 +0000 (18:21 +0000)]
Auto merge of #30325 - jseyfried:fixes_30078, r=nrc
This fixes a bug in which unused imports can get wrongly marked as used when checking for unused qualifications in `resolve_path` (issue #30078), and it removes unused imports that were previously undetected because of the bug.
Steve Wooster [Thu, 17 Dec 2015 17:40:02 +0000 (09:40 -0800)]
Change "big ask" to "tall order" in Rustonomicon.
The Rustonomicon's Lifetimes chapter uses the idiom "big ask", which is obscure compared to "tall order" (check Google ngrams). Also, it's easily mistaken for a typo; either "a big task" or "a big thing to ask" could plausibly work there.
bors [Wed, 16 Dec 2015 22:53:19 +0000 (22:53 +0000)]
Auto merge of #30341 - pnkfelix:call-site-scope, r=nikomatsakis
Ensure borrows of fn/closure params do not outlive invocations.
Does this by adding a new CallSiteScope to the region (or rather code extent) hierarchy, which outlives even the ParameterScope (which in turn outlives the DestructionScope of a fn/closure's body).
bors [Wed, 16 Dec 2015 20:22:07 +0000 (20:22 +0000)]
Auto merge of #29962 - aturon:coherence-errors, r=nmatsakis
Currently, a coherence error based on overlapping impls simply mentions
the trait, and points to the two conflicting impls:
```
error: conflicting implementations for trait `Foo`
```
With this commit, the error will include all input types to the
trait (including the `Self` type) after unification between the
overlapping impls. In other words, the error message will provide
feedback with full type details, like:
```
error: conflicting implementations of trait `Foo<u32>` for type `u8`:
```
When the `Self` type for the two impls unify to an inference variable,
it is elided in the output, since "for type `_`" is just noise in that
case.
Aaron Turon [Tue, 1 Dec 2015 19:26:47 +0000 (11:26 -0800)]
Provide overlapping types for coherence errors
Currently, a coherence error based on overlapping impls simply mentions
the trait, and points to the two conflicting impls:
```
error: conflicting implementations for trait `Foo`
```
With this commit, the error will include all input types to the
trait (including the `Self` type) after unification between the
overlapping impls. In other words, the error message will provide
feedback with full type details, like:
```
error: conflicting implementations of trait `Foo<u32>` for type `u8`:
```
When the `Self` type for the two impls unify to an inference variable,
it is elided in the output, since "for type `_`" is just noise in that
case.
Alex Crichton [Wed, 16 Dec 2015 16:06:27 +0000 (08:06 -0800)]
mk: Use the right llvmdeps.rs file for cross build
It looks like #27937 accidentally switched the llvmdeps file from the target to
the host by accident, so be sure to use the right llvmdeps file which is built
for the target when building rustc_llvm
Rollup merge of #30368 - arielb1:region-unification-2, r=nikomatsakis
Turns out that calling `resolve_type_variables_if_possible` in a O(n^2)
loop is a bad idea. Now we just resolve each copy of the region variable
to its lowest name each time (we resolve the region variable to its lowest
name, rather than to its unify-table name to avoid the risk of
the unify-table name changing infinitely many times. That may be
not a problem in practice, but I am not sure of it).
Rollup merge of #30320 - nrc:err-names, r=@nikomatsakis
We can now handle name resolution errors and get past type checking (if we're a bit lucky). This is the first step towards doing code completion for partial programs (we need error recovery in the parser and early access to save-analysis).
bors [Wed, 16 Dec 2015 10:09:36 +0000 (10:09 +0000)]
Auto merge of #30300 - sanxiyn:syntax-ext, r=nikomatsakis
This reduces iteration time (`make rustc-stage1`) for moved syntax extensions from 11 minutes to 3 minutes on my machine.
Because of the signature change, this is a [breaking-change] for people directly calling `expand_crate`. I think it is rare: from GitHub search, only case I found is [glassful](https://github.com/kmcallister/glassful).
The attributes `deprecated` and `rustc_deprecated` are completely independent in this implementation and it leads to some noticeable code duplication. Representing `deprecated` as
```
Stability {
level: Stable { since: "" },
feature: "",
depr: Some(Deprecation),
}
```
or, contrariwise, splitting rustc_deprecation from stability makes most of the duplication go away.
I can do this refactoring, but before doing it I must be sure, that further divergence of `deprecated` and `rustc_deprecated` is certainly not a goal.
Alex Burka [Wed, 16 Dec 2015 01:48:25 +0000 (20:48 -0500)]
change macro ambiguity example from ty to ident
The previous example had no chance of compiling in either form, due to the restrictive follow set for `ty`. This one has the desired behavior: http://is.gd/kYdw4g (well, I don't exactly desire this behavior at all, but it's true at least :p )