kennytm [Tue, 13 Nov 2018 05:03:22 +0000 (13:03 +0800)]
Rollup merge of #55889 - RalfJung:global-alloc, r=alexcrichton
global allocators: add a few comments
These comments answer some questions that came up when I tried to understand how the control flow works for the global allocator, `Global` and `System`.
This makes `PhantomData<T>` structurally matchable, irrespective of whether `T` is, per the discussion on this week's language team meeting (the general consensus was that this was a bug-fix).
All types containing `PhantomData<T>` and which used `#[derive(PartialEq, Eq)]` and were previously not `#[structural_match]` only because of `PhantomData<T>` will now be `#[structural_match]`.
kennytm [Tue, 13 Nov 2018 05:03:08 +0000 (13:03 +0800)]
Rollup merge of #55804 - QuietMisdreavus:eager-crate-inline, r=pnkfelix
rustdoc: don't inline `pub use some_crate` unless directly asked to
cc https://github.com/rust-lang/rust/issues/52509 (fixes it? i'm not sure about my comment summoning the docs team)
When rustdoc encounters a `pub use` statement for an item from another crate, it will eagerly inline its contents into your crate. This somewhat clashes with the new paths behavior in Rust 2018, in which crates are implicitly linked and re-exported with `pub use` instead of `pub extern crate`. In rust 2015, `pub extern crate` would only create a single line for its re-export in the docs, so i'm making it do the same with `pub use some_crate;`.
The exact new behavior is like this: *If rustdoc sees a `pub use` statement, and the item being imported is the root of another crate, it will only inline it if `#[doc(inline)]` is provided.* I made it only avoid crate roots because otherwise it would stop inlining any module, which may or may not be what people want.
bors [Tue, 13 Nov 2018 01:08:13 +0000 (01:08 +0000)]
Auto merge of #55052 - newpavlov:patch-2, r=alexcrichton
Use read_unaligned instead of read in transmute_copy
Closes: #55044
This change could result in performance regression on non-x86 platforms. (but it also can fix some of UB which lurks in existing programs) An alternative would be to update `transmute_copy` documentation with alignment requirements.
bors [Mon, 12 Nov 2018 18:54:11 +0000 (18:54 +0000)]
Auto merge of #55278 - Centril:constification-1, r=alexcrichton
Minor standard library constification
This PR makes some bits of the standard library into `const fn`s.
I've tried to be as aggressive as I possibly could in the constification.
The list is rather small due to how restrictive `const fn` is at the moment.
bors [Mon, 12 Nov 2018 04:12:26 +0000 (04:12 +0000)]
Auto merge of #55701 - tromey:ice-fix, r=matthewjasper
Fix emission of niche-filling discriminant values
Bug #55606 points out a regression introduced by #54004; namely that
an assertion can erroneously fire when a niche-filling discriminant
value is emitted.
This fixes the bug by removing the assertion, and furthermore by
arranging for the discriminant value to be masked according to the
size of the niche. This makes handling the discriminant a bit simpler
for debuggers.
bors [Mon, 12 Nov 2018 01:20:33 +0000 (01:20 +0000)]
Auto merge of #55525 - nnethercote:MatcherPos-stack-SmallVec, r=nnethercote
Make `MatcherPos::stack` a `SmallVec`.
This avoids some allocations.
This seems like a trivial change, but the compiler rejects it:
```
Compiling syntax v0.0.0 (/home/njn/moz/rust1/src/libsyntax)
error[E0597]: `initial` does not live long enough=========> ] 89/110: syntax
--> libsyntax/ext/tt/macro_parser.rs:647:57
|
647 | let mut cur_items = smallvec![MatcherPosHandle::Ref(&mut initial)];
| ^^^^^^^^^^^^ borrowed value does not live long enough
...
762 | }
| -
| |
| `initial` dropped here while still borrowed
| borrow later used here, when `initial` is dropped
error: aborting due to previous error
```
This is either a compiler bug, or there's some subtle thing I don't understand. The lifetimes sure seem straightforward: `initial` is declared, and then `cur_items` is declared immediately afterward, and it uses a reference to `initial`. The error message makes it sound like the compiler is dropping the variables in the wrong order.
bors [Sun, 11 Nov 2018 19:51:56 +0000 (19:51 +0000)]
Auto merge of #55660 - alexcrichton:cleanup-alloc-system, r=dtolnay,SimonSapin
Remove the `alloc_system` crate
In what's hopefully one of the final nails in the coffin of the "old allocator story of yore" this PR deletes the `alloc_system` crate and all traces of it from the compiler. The compiler no longer needs to inject allocator crates anywhere and the `alloc_system` crate has no real reason to exist outside the standard library.
The unstable `alloc_system` crate is folded directly into the standard library where its stable interface, the `System` type, remains the same. All unstable traces of `alloc_system` are removed, however.
Alex Crichton [Sat, 3 Nov 2018 18:15:48 +0000 (11:15 -0700)]
std: Delete the `alloc_system` crate
This commit deletes the `alloc_system` crate from the standard
distribution. This unstable crate is no longer needed in the modern
stable global allocator world, but rather its functionality is folded
directly into the standard library. The standard library was already the
only stable location to access this crate, and as a result this should
not affect any stable code.
Alex Crichton [Sat, 3 Nov 2018 17:51:31 +0000 (10:51 -0700)]
rustc: Clean up allocator injection logic
This commit cleans up allocator injection logic found in the compiler
around selecting the global allocator. It turns out that now that
jemalloc is gone the compiler never actually injects anything! This
means that basically everything around loading crates here and there can
be easily pruned.
This also removes the `exe_allocation_crate` option from custom target
specs as it's no longer used by the compiler anywhere.
bors [Sun, 11 Nov 2018 17:05:36 +0000 (17:05 +0000)]
Auto merge of #55657 - davidtwco:issue-55651, r=pnkfelix
NLL Diagnostic Review 3: Unions not reinitialized after assignment into field
Fixes #55651, #55652.
This PR makes two changes:
First, it updates the dataflow builder to add an init for the place
containing a union if there is an assignment into the field of
that union.
Second, it stops a "use of uninitialized" error occuring when there is an
assignment into the field of an uninitialized union that was previously
initialized. Making this assignment would re-initialize the union, as
tested in `src/test/ui/borrowck/borrowck-union-move-assign.nll.stderr`.
The check for previous initialization ensures that we do not start
supporting partial initialization yet (cc #21232, #54499, #54986).
This PR also fixes #55652 which was marked as requiring investigation
as the changes in this PR add an error that was previously missing
(and mentioned in the review comments) and confirms that the error
that was present is correct and a result of earlier partial
initialization changes in NLL.
r? @pnkfelix (due to earlier work with partial initialization)
cc @nikomatsakis
kennytm [Sun, 11 Nov 2018 04:34:23 +0000 (12:34 +0800)]
Rollup merge of #55856 - QuietMisdreavus:static-discharge, r=GuillaumeGomez
rustdoc: refactor: move all static-file include!s into a single module
This is a smaller refactor that creates a new module `rustdoc::html::static_files`, which contains a bunch of `static` variables with all the files in `html/static` that we use. The idea behind moving them all here was to remove the duplicate `include_bytes!()` that are used by the theme-checker code. It also continues to centralize more operations in rustdoc.
kennytm [Sun, 11 Nov 2018 04:33:50 +0000 (12:33 +0800)]
Rollup merge of #55845 - nikic:emscripten-clamp-mode, r=alexcrichton
Set BINARYEN_TRAP_MODE=clamp
This fixes the wasm32-unknown-emscripten test failure mentioned in https://github.com/rust-lang/rust/pull/55626#issuecomment-437084774, by making binaryen operate in clamp rather than trap mode.
The issue is that the current `-Zsaturating-float-casts` implementation uses `fpto[us]i` unconditionally (and selects afterwards), which does not work with trapping implementations of fpto[su]i, which emscripten uses by default.
I've left a FIXME to drop this flag once we have a better solution for saturating casts on the LLVM side.
;
kennytm [Sun, 11 Nov 2018 04:32:01 +0000 (12:32 +0800)]
Rollup merge of #55630 - petrochenkov:noprelude, r=Centril
resolve: Filter away macro prelude in modules with `#[no_implicit_prelude]` on 2018 edition
This is a tiny thing.
For historical reasons macro prelude (macros from `#[macro_use] extern crate ...`, including `extern crate std`) is still available in modules with `#[no_implicit_prelude]`.
This PR provides proper isolation and removes those names from scope.
`#[no_implicit_prelude]` modules still have built-in types (`u8`), built-in attributes (`#[inline]`) and built-in macros (`env!("PATH")`) in scope. We can introduce some `#[no_implicit_prelude_at_all]` to remove those as well, but that's a separate issue.
The change is done only on 2018 edition for backward compatibility.
I'm pretty sure this can be done on 2015 as well because `#[no_implicit_prelude]` is rarely used, but I don't want to go through the crater/deprecation process right now, maybe later.
cc https://github.com/rust-lang/rust/issues/53977
r? @ghost
bors [Sun, 11 Nov 2018 03:44:16 +0000 (03:44 +0000)]
Auto merge of #54993 - TimNN:pda-tdl, r=eddyb
Support for the program data address space option of LLVM's Target Datalayout
This was introduced recently (specifically, for AVR, cc @dylanmckay).
(I came up with this when attempting to run [avr-rust](https://github.com/avr-rust/rust) rebased on the latest [rust-lang](https://github.com/rust-lang/rust) commits. If this requires a different design, some additional discussions, or is not something to pursue right now, I'd be happy to close this PR).
Note that this somewhat overlaps with @DiamondLovesYou's #51576, I think, although the implementation here is significantly simpler: Since the address space applies to _all_ program data, we can just check the pointee's type whenever we create an LLVM pointer type. If it is a function we use the program data address space; if not we use the default address space.
Pietro Albini [Sat, 10 Nov 2018 23:21:19 +0000 (00:21 +0100)]
Rollup merge of #55802 - wesleywiser:inlined_calls_2_electric_boogaloo, r=nagisa
Don't inline virtual calls (take 2)
When I fixed the previous mis-optimizations, I didn't realize there were
actually two different places where we mutate `callsites` and both of
them should have the same behavior.
As a result, if a function was inlined and that function contained
virtual function calls, they were incorrectly being inlined. I also
added a test case which covers this.
Pietro Albini [Sat, 10 Nov 2018 23:21:17 +0000 (00:21 +0100)]
Rollup merge of #55801 - pnkfelix:update-box-insensitivity-test-for-nll, r=davidtwco
NLL: Update box insensitivity test
This is just keeping one of our tests honest with respect to NLL, in two ways:
1. Adds uses of borrows that would otherwise be too short to observe the error that we would have expected to see...
2. ... I say "would have expected" because all of the errors in this file are part of the reversion of rust-lang/rfcs#130 that is attached to NLL (you can see more discussion of this here https://github.com/rust-lang/rust/issues/43234#issuecomment-411017768 )
Pietro Albini [Sat, 10 Nov 2018 23:21:11 +0000 (00:21 +0100)]
Rollup merge of #55687 - alexreg:fix-24010, r=scalexm
Take supertraits into account when calculating associated types
Fixes #24010 and #23856. Applies to trait aliases too.
As a by-product, this PR also makes repeated bindings of the same associated item in the same definition a hard error. This was previously a warning with a note about it becoming a hard error in the future. See #50589 for more info.
I talked about this with @nikomatsakis recently, but only very superficially, so this shouldn't stop anyone from assigning it to themself to review and r+.
N.B. The "WIP" commits represent imperfect attempts to solve the problem just for trait objects, but I've left them in for reference for the sake of whomever is reviewing this.
bors [Sat, 10 Nov 2018 23:16:25 +0000 (23:16 +0000)]
Auto merge of #54864 - ljedrz:cleanup_codegen_llvm_back, r=Mark-Simulacrum
Cleanup codegen_llvm/back
- improve allocations
- use `Cow<'static, str>` where applicable
- use `to_owned` instead of `to_string` with string literals
- remove a redundant `continue`
- possible minor speedup in logic
- use `mem::replace` instead of `swap` where more concise
- remove `'static` from consts
- improve common patterns
- remove explicit `return`s
- whitespace & formatting fixes
bors [Sat, 10 Nov 2018 19:58:14 +0000 (19:58 +0000)]
Auto merge of #55650 - nikic:funnel-shift, r=nagisa
Implement rotate using funnel shift on LLVM >= 7
Implement the rotate_left and rotate_right operations using
llvm.fshl and llvm.fshr if they are available (LLVM >= 7).
Originally I wanted to expose the funnel_shift_left and
funnel_shift_right intrinsics and implement rotate_left and
rotate_right on top of them. However, emulation of funnel
shifts requires emitting a conditional to check for zero shift
amount, which is not necessary for rotates. I was uncomfortable
doing that here, as I don't want to rely on LLVM to optimize
away that conditional (and for variable rotates, I'm not sure it
can). We should revisit that question when we raise our minimum
version requirement to LLVM 7 and don't need emulation code
anymore.
Wesley Wiser [Wed, 7 Nov 2018 03:31:09 +0000 (22:31 -0500)]
Don't inline virtual calls (take 2)
When I fixed the previous mis-optimizations, I didn't realize there were
actually two different places where we mutate `callsites` and both of
them should have the same behavior.
As a result, if a function was inlined and that function contained
virtual function calls, they were incorrectly being inlined. I also
added a test case which covers this.
bors [Sat, 10 Nov 2018 01:16:02 +0000 (01:16 +0000)]
Auto merge of #55626 - nikic:update-emscripten, r=alexcrichton
Update emscripten
This updates emscripten to 1.38.15, which is based on LLVM 6.0.1 and would allow us to drop code for handling LLVM 4.
The main issue I ran into is that exporting statics through `EXPORTED_FUNCTIONS` no longer works. As far as I understand exporting non-functions doesn't really make sense under emscripten anyway, so I've modified the symbol export code to not even try.