Rollup merge of #35751 - nagisa:mir-scope-fix-again, r=eddyb
Fix the invalidation of the MIR early exit cache
~~The #34307 introduced a cache for early exits in order to help with O(n*m) explosion of cleanup blocks but the cache is invalidated incorrectly and I can’t seem to figure out why (caching is hard!)~~
~~Remove the cache for now to fix the immediate correctness issue and worry about the performance later.~~
Rollup merge of #35734 - japaric:mips-uclibc, r=alexcrichton
add mips-uclibc targets
These targets cover OpenWRT 15.05 devices, which use the soft float ABI
and the uclibc library. None of the other built-in mips targets covered
those devices (mips-gnu is hard float and glibc-based, mips-musl is
musl-based).
With this commit one can now build std for these devices using these
commands:
```
$ configure --enable-rustbuild --target=mips-unknown-linux-uclibc
$ make
```
cc #35673
---
r? @alexcrichton
cc @felixalias This is the target the rust-tessel project should be using.
Note that the libc crate doesn't support the uclibc library and will have to be updated. We are lucky that uclibc and glibc are somewhat similar and one can build std and even run the libc-test test suite with the current, unmodified libc. About that last part, I tried to run the libc-test and got a bunch of compile errors. I don't intend to fix them but I'll post some instruction about how to run libc-test in the rust-lang/libc issue tracker.
Jonathan Turner [Wed, 17 Aug 2016 13:25:26 +0000 (06:25 -0700)]
Rollup merge of #35695 - matthew-piziak:vec-assert-over-println, r=GuillaumeGomez
accumulate into vector and assert, instead of printing
I'm only making this change in one place so that people can express
their preferences for this stylistic change. If/when this change is
approved I'll go ahead and translate the rest of the `std::ops`
examples.
Jonathan Turner [Wed, 17 Aug 2016 13:25:25 +0000 (06:25 -0700)]
Rollup merge of #35663 - CryZe:no-stdlib, r=Manishearth
Improve `No stdlib` and related Documentation
This renames all lang item function names to the ones used in `libstd` and `libpanic_unwind`. It also explains the `eh_unwind_resume` lang item in the `libcore` documentation, where it was missing. A third function is also needed on certain compilation targets, so this was also added to the `No stdlib` documentation.
Jonathan Turner [Wed, 17 Aug 2016 13:25:24 +0000 (06:25 -0700)]
Rollup merge of #35613 - matthew-piziak:array-docs-trait-justification, r=steveklabnik
provide additional justification for array interface design
Explain why Rust does not implement traits for large arrays.
Explain why most methods are implemented on slices rather than arrays.
Note: I'm dipping my toes in the water with a tiny PR. Especially looking for feedback on wording and style. Points of concern: appropriate level of top-level explanation; foreshadowing (is it appropriate to imply that we expect Rust's type system to eventually support size-generic arrays?); using `Foo` and `Bar` as type variables instead of e.g. `T` and `S`.
Jonathan Turner [Wed, 17 Aug 2016 13:25:24 +0000 (06:25 -0700)]
Rollup merge of #35610 - JessRudder:33637-doc-update-for-str-representaton, r=steveklabnik
Add note to docs for &str that example is to demo internals only
r? @steveklabnik
This adds a note below the &str representation example explaining that the example provided should not be used under normal circumstances..
Would it make sense to point people in the direction of the method(s) they should use instead? I left it out in the interest of not complicating the documentation, but, there's definitely an argument to be made for adding a bit of guidance in there.
bors [Wed, 17 Aug 2016 05:52:55 +0000 (22:52 -0700)]
Auto merge of #35605 - eddyb:substs, r=nikomatsakis
Remove the ParamSpace separation from formal and actual generics in rustc.
This is the first step towards enabling the typesystem implemented by `rustc` to be extended
(with generic modules, HKT associated types, generics over constants, etc.).
The current implementation splits all formal (`ty::Generics`) and actual (`Substs`) lifetime and type parameters (and even `where` clauses) into 3 "parameter spaces":
* `TypeSpace` for `enum`, `struct`, `trait` and `impl`
* `SelfSpace` for `Self` in a `trait`
* `FnSpace` for functions and methods
For example, in `<X as Trait<A, B>>::method::<T, U>`, the `Substs` are `[[A, B], [X], [T, U]]`.
The representation uses a single `Vec` with 2 indices where it's split into the 3 "parameter spaces".
Such a simplistic approach doesn't scale beyond the Rust 1.0 typesystem, and its existence was mainly motivated by keeping code manipulating generic parameters correct, across all possible situations.
Summary of changes:
* `ty::Generics` are uniformly stored and can be queried with `tcx.lookup_generics(def_id)`
* the `typeck::collect` changes for this resulted in a function to lazily compute the `ty::Generics` for a local node, given only its `DefId` - this can be further generalized to other kinds of type information
* `ty::Generics` and `ty::GenericPredicates` now contain only their own parameters (or `where` clauses, respectively), and refer to their "parent", forming a linked list
* right now most items have one level of nesting, only associated items and variants having two
* in the future, if `<X as mod1<A>::mod2<B>::mod3::Trait<C>>::Assoc<Y>` is supported, it would be represented by item with the path `mod1::mod2::mod3::Trait::Assoc`, and 4 levels of generics: `mod1` with `[A]`, `mod2` with `[B]`, `Trait` with `[X, C]` and `Assoc` with `[Y]`
* `Substs` gets two new APIs for working with arbitrary items:
* `Substs::for_item(def_id, mk_region, mk_type)` will construct `Substs` expected by the definition `def_id`, calling `mk_region` for lifetime parameters and `mk_type` for type parameters, and it's guaranteed to *always* return `Substs` compatible with `def_id`
* `substs.rebase_onto(from_base_def_id, to_base_substs)` can be used if `substs` is for an item nested within `from_base_def_id` (e.g. an associated item), to replace the "outer parameters" with `to_base_substs` - for example, you can translate a method's `Substs` between a `trait` and an `impl` (in both directions) if you have the `DefId` of one and `Substs` for the other
* trait objects, without a `Self` in their `Substs`, use *solely* `ExistentialTraitRef` now, letting `TraitRef` assume it *always* has a `Self` present
* both `TraitRef` and `ExistentialTraitRef` get methods which do operations on their `Substs` which are valid only for traits (or trait objects, respectively)
* `Substs` loses its "parameter spaces" distinction, with effectively no code creating `Substs` in an ad-hoc manner, or inspecting them, without knowing what shape they have already
Future plans:
* combine both lifetimes and types in a single `Vec<Kind<'tcx>>` where `Kind` would be a tagged pointer that can be `Ty<'tcx>`, `&'tcx ty::Region` or, in the future, potentially-polymorphic constants
* this would require some performance investigation, if it implies a lot of dynamic checks
* introduce an abstraction for `(T, Substs)`, where the `Substs` are even more hidden away from code
manipulating it; a precedent for this is `Instance` in trans, which has `T = DefId`; @nikomatsakis also referred to this, as "lazy substitution", when `T = Ty`
* rewrite type pretty-printing to fully take advantage of this to inject actual in the exact places of formal generic parameters in any paths
* extend the set of type-level information (e.g. beyond `ty::Generics`) that can be lazily queried during `typeck` and introduce a way to do those queries from code that can't refer to `typeck` directly
* this is almost unrelated but is necessary for DAG-shaped recursion between constant evaluation and type-level information, i.e. for implementing generics over constants
r? @nikomatsakis
cc @rust-lang/compiler
cc @nrc Could get any perf numbers ahead of merging this?
bors [Wed, 17 Aug 2016 02:44:10 +0000 (19:44 -0700)]
Auto merge of #35559 - frewsxcv:slice-iter-as-ref, r=alexcrichton
Implement `AsRef<[T]>` for `std::slice::Iter`.
`AsRef` is designed for conversions that are "cheap" (as per
the API docs). It is the case that retrieving the underlying
data of `std::slice::Iter` is cheap. In my opinion, there's no
ambiguity about what slice data will be returned, otherwise,
I would be more cautious about implementing `AsRef`.
bors [Tue, 16 Aug 2016 23:35:10 +0000 (16:35 -0700)]
Auto merge of #35538 - cgswords:libproc_macro, r=nrc
Kicking off libproc_macro
This PR introduces `libproc_macro`, which is currently quite bare-bones (just a few macro construction tools and an initial `quote!` macro).
This PR also introduces a few test cases for it, and an additional `shim` file (at `src/libsyntax/ext/proc_macro_shim.rs` to allow a facsimile usage of Macros 2.0 *today*!
Jorge Aparicio [Tue, 16 Aug 2016 22:07:55 +0000 (17:07 -0500)]
add mips-uclibc targets
These targets cover OpenWRT 15.05 devices, which use the soft float ABI
and the uclibc library. None of the other built-in mips targets covered
those devices (mips-gnu is hard float and glibc-based, mips-musl is
musl-based).
With this commit one can now build std for these devices using these
commands:
```
$ configure --enable-rustbuild --target=mips-unknown-linux-uclibc
$ make
```
Corey Farwell [Wed, 10 Aug 2016 00:49:41 +0000 (20:49 -0400)]
Implement `AsRef<[T]>` for `std::slice::Iter`.
`AsRef` is designed for conversions that are "cheap" (as per
the API docs). It is the case that retrieving the underlying
data of `std::slice::Iter` is cheap. In my opinion, there's no
ambiguity about what slice data will be returned, otherwise,
I would be more cautious about implementing `AsRef`.
bors [Tue, 16 Aug 2016 07:12:12 +0000 (00:12 -0700)]
Auto merge of #35162 - canndrew:bang_type_coerced, r=nikomatsakis
Implement the `!` type
This implements the never type (`!`) and hides it behind the feature gate `#[feature(never_type)]`. With the feature gate off, things should build as normal (although some error messages may be different). With the gate on, `!` is usable as a type and diverging type variables (ie. types that are unconstrained by anything in the code) will default to `!` instead of `()`.
Matthew Piziak [Mon, 15 Aug 2016 22:03:11 +0000 (18:03 -0400)]
accumulate into vector and assert, instead of printing
I'm only making this change in one place so that people can express
their preferences for this stylistic change. If/when this change is
approved I'll go ahead and translate the rest of the `std::ops`
examples.
bors [Mon, 15 Aug 2016 15:35:18 +0000 (08:35 -0700)]
Auto merge of #35340 - michaelwoerister:incr-comp-cli-args, r=nikomatsakis
Take commandline arguments into account for incr. comp.
Implements the conservative strategy described in https://github.com/rust-lang/rust/issues/33727.
From now one, every time a new commandline option is added, one has to specify if it influences the incremental compilation cache. I've tried to implement this as automatic as possible: One just has to added either the `[TRACKED]` or the `[UNTRACKED]` marker next to the field. The `Options`, `CodegenOptions`, and `DebuggingOptions` definitions in `session::config` show plenty of examples.
The PR removes some cruft from `session::config::Options`, mostly unnecessary copies of flags also present in `DebuggingOptions` or `CodeGenOptions` in the same struct.
One notable removal is the `cfg` field that contained the values passed via `--cfg` commandline arguments. I chose to remove it because (1) its content is only a subset of what later is stored in `hir::Crate::config` and it's pretty likely that reading the cfgs from `Options` would not be what you wanted, and (2) we could not incorporate it into the dep-tracking hash of the `Options` struct because of how the test framework works, leaving us with a piece of untracked but vital data.
It is now recommended (just as before) to access the crate config via the `krate()` method in the HIR map.
Because the `cfg` field is not present in the `Options` struct any more, some methods in the `CompilerCalls` trait now take the crate config as an explicit parameter -- which might constitute a breaking change for plugin authors.