Rollup merge of #61043 - alexcrichton:less-full-bootstrap, r=sanxiyn
Disable LLVM/debug assertions in gnu-full-bootstrap
This builder already is very close to the 2 hour mark and the debug
assertions aren't really buying us anything over what all the other
containers are enabling, so let's disable them for this slow builder.
Rollup merge of #61014 - jsgf:emit-artifact-type, r=alexcrichton
Make -Zemit-artifact-notifications also emit the artifact type
This is easier for tooling to handle than trying to reverse-engineer the type from the filename extension. The field name and value is intended to reflect the `--emit` command-line option.
Related issues https://github.com/rust-lang/rust/issues/60988 https://github.com/rust-lang/rust/issues/58465
cc @alexcrichton
Rollup merge of #60981 - alexcrichton:update-compiler-builtins, r=cuviper
Bump compiler-builtins to 0.1.15
This commit bumps the `compiler-builtins` dependency to 0.1.15 which
expects to have the source for `compiler-rt` provided externally if the
`c` feature is enabled. This then plumbs through the necessary support
in the build system to ensure that if the `llvm-project` directory is
checked out and present that we enable the `c` feature of
`compiler-builtins` and compile in all the C intrinsics.
bors [Wed, 22 May 2019 22:57:48 +0000 (22:57 +0000)]
Auto merge of #61044 - Centril:rollup-ztsgb9p, r=Centril
Rollup of 8 pull requests
Successful merges:
- #60300 (Allow null-pointer-optimized enums in FFI if their underlying representation is FFI safe)
- #60773 (Always try to project predicates when finding auto traits in rustdoc)
- #60809 (Add FAQ for NLL migration)
- #61023 (Migrate from recursion to iterate on qualify consts visitor impl)
- #61029 (Simplify RefCell minimum_spanning_tree example)
- #61030 (Make maybe_codegen_consume_direct iterate instead of doing recursion)
- #61034 (rustc_metadata: parametrize schema::CrateRoot by 'tcx and rip out old unused incremental infra.)
- #61037 (Update clippy submodule)
Rollup merge of #61037 - oli-obk:clippy, r=Manishearth
Update clippy submodule
r? @Manishearth
If anyone is wondering where the odd old commits are coming from, we merged all beta backport commits and so into master in order to make sure we don't need to keep those branches around.
Rollup merge of #61029 - blkerby:minimum_spanning_tree, r=alexcrichton
Simplify RefCell minimum_spanning_tree example
This simplifies the implementation of the `minimum_spanning_tree` example of `RefCell` in the `cell` module-level docs, avoiding an unnecessary recursive call. This also eliminates the need for a block to contain the scope of the borrow in this example. But since that use of a block served an important didactic purpose, we make up for this by instead introducing a block in the initial, simpler example of `RefCell`, where the point will hopefully be conveyed to the reader more easily.
Rollup merge of #60773 - Aaron1011:fix/rustdoc-project-all, r=eddyb
Always try to project predicates when finding auto traits in rustdoc
Fixes #60726
Previous, AutoTraitFinder would only try to project predicates when the
predicate type contained an inference variable. When finding auto
traits, we only project to try to unify inference variables - we don't
otherwise learn any new information about the required bounds.
However, this lead to failing to properly generate a negative auto trait
impl (indicating that a type never implements a certain auto trait) in
the following unusual scenario:
In almost all cases, a type has an (implicit) negative impl of an auto
trait due some other type having an explicit *negative* impl of that
auto trait. For example:
struct MyType<T> {
field: *const T
}
has an implicit 'impl<T> !Send for MyType<T>', due to the explicit
negative impl (in libcore) 'impl<T: ?Sized> !Send for *const T'.
However, as exposed by the 'abi_stable' crate, this isn't always the
case. This minimzed example shows how a type can never implement
'Send', due to a projection error:
```
pub struct True;
pub struct False;
pub trait MyTrait {
type Project;
}
pub struct MyStruct<T> {
field: T
}
impl MyTrait for u8 {
type Project = False;
}
unsafe impl<T> Send for MyStruct<T>
where T: MyTrait<Project=True> {}
pub struct Wrapper {
inner: MyStruct<u8>
}
```
In this example, `<u8 as MyTrait>::Project == True'
must hold for 'MyStruct<u8>: Send' to hold.
However, '<u8 as MyTrait>::Project == False' holds instead
To properly account for this unusual case, we need to call
'poly_project_and_unify' on *all* predicates, not just those with
inference variables. This ensures that we catch the projection error
that occurs above, and don't incorrectly determine that 'Wrapper: Send'
holds.
Rollup merge of #60300 - mjbshaw:ffi_types, r=rkruppe
Allow null-pointer-optimized enums in FFI if their underlying representation is FFI safe
I'm not sure if this requires an RFC. I attempted to start [a discussion on internals.rust-lang.org](https://internals.rust-lang.org/t/options-ffi-safety-and-guarantees-for-abi-compatibility-with-nonnull-optimizations/9784) and when no one really objected I figured I'd go ahead and try implementing this.
This allows types like `Option<NonZeroU8>` to be used in FFI without triggering the `improper_ctypes` lint. This works by changing the `is_repr_nullable_ptr` function to consider an enum `E` to be FFI-safe if:
- `E` has no explicit `#[repr(...)]`.
- It only has two variants.
- One of those variants is empty (meaning it has no fields).
- The other variant has only one field.
- That field is one of the following:
- `&T`
- `&mut T`
- `extern "C" fn`
- `core::num::NonZero*`
- `core::ptr::NonNull<T>`
- `#[repr(transparent)] struct` wrapper around one of the types in this list.
- The size of `E` and its field are both known and are both the same size (implying `E` is participating in the nonnull optimization).
This logic seems consistent with [the Rust nomicon](https://doc.rust-lang.org/nomicon/repr-rust.html).
Alex Crichton [Wed, 22 May 2019 15:02:19 +0000 (08:02 -0700)]
Disable LLVM/debug assertions in gnu-full-bootstrap
This builder already is very close to the 2 hour mark and the debug
assertions aren't really buying us anything over what all the other
containers are enabling, so let's disable them for this slow builder.
Alex Crichton [Mon, 20 May 2019 18:00:34 +0000 (11:00 -0700)]
Bump compiler-builtins to 0.1.15
This commit bumps the `compiler-builtins` dependency to 0.1.15 which
expects to have the source for `compiler-rt` provided externally if the
`c` feature is enabled. This then plumbs through the necessary support
in the build system to ensure that if the `llvm-project` directory is
checked out and present that we enable the `c` feature of
`compiler-builtins` and compile in all the C intrinsics.
Michael Bradshaw [Wed, 22 May 2019 13:49:43 +0000 (06:49 -0700)]
Allow null-pointer-optimized enums in FFI if their underlying representation is FFI safe
This allows types like Option<NonZeroU8> to be used in FFI without triggering the improper_ctypes lint. This works by changing the is_repr_nullable_ptr function to consider an enum E to be FFI-safe if:
- E has no explicit #[repr(...)].
- It only has two variants.
- One of those variants is empty (meaning it has no fields).
- The other variant has only one field.
- That field is one of the following:
- &T
- &mut T
- extern "C" fn
- core::num::NonZero*
- core::ptr::NonNull<T>
- #[repr(transparent)] struct wrapper around one of the types in this list.
- The size of E and its field are both known and are both the same size (implying E is participating in the nonnull optimization).
bors [Wed, 22 May 2019 08:22:17 +0000 (08:22 +0000)]
Auto merge of #59445 - alexreg:ban-multi-trait-objects-via-aliases, r=oli-obk
Ban multi-trait objects via trait aliases
Obviously, multi-trait objects are not normally supported, so they should not be supported via trait aliases.
This has been factored out from the previous PR https://github.com/rust-lang/rust/pull/55994 (see point 1).
r? @Centril
CC @nikomatsakis
------------------
### RELNOTES:
We now allow `dyn Send + fmt::Debug` with equivalent semantics to `dyn fmt::Debug + Send`.
That is, the order of the mentioned traits does not matter wrt. principal/not-principal traits.
This is a small change that might deserve a mention in the blog post because it is a language change but most likely not.
bors [Wed, 22 May 2019 04:42:20 +0000 (04:42 +0000)]
Auto merge of #60840 - tmandry:preserve-scope-in-generator-mir, r=cramertj
Preserve local scopes in generator MIR
Part of #52924, depended upon by the generator layout optimization #60187.
This PR adds `StorageDead` statements in more places in generators, so we can see when non-`Drop` locals have gone out of scope and recover their storage.
The reason this is only done for generators is compiler performance. See https://github.com/rust-lang/rust/pull/60187#issuecomment-485637811 for what happens when we do this for all functions.
For `Drop` locals, we modify the `MaybeStorageLive` analysis to use `drop` to indicate that storage is no longer live for the local. Once `drop` returns or unwinds to our function, we implicitly assume that the local is `StorageDead`.
Instead of using `drop`, it is possible to emit more `StorageDead` statements in the MIR for `Drop` locals so we can handle all locals the same. I am fine with doing it that way, but this was the simplest approach for my purposes. It is also likely to be more performant.
r? @Zoxc (feel free to reassign)
cc @cramertj @eddyb @RalfJung @rust-lang/wg-async-await
bors [Wed, 22 May 2019 01:51:31 +0000 (01:51 +0000)]
Auto merge of #61027 - Centril:rollup-oewauf1, r=Centril
Rollup of 10 pull requests
Successful merges:
- #59742 (Move `edition` outside the hygiene lock and avoid accessing it)
- #60581 (convert custom try macro to `?`)
- #60963 (Update boxed::Box docs on memory layout)
- #60973 (Avoid symbol interning in `file_metadata`.)
- #60982 (Do not fail on child without DefId)
- #60991 (LocalDecl push returns Local len)
- #60995 (Add stream_to_parser_with_base_dir)
- #60998 (static_assert: make use of anonymous constants)
- #61003 (Remove impls for `InternedString`/string equality.)
- #61006 (adjust deprecation date of mem::uninitialized)
Rollup merge of #61006 - RalfJung:maybe-uninit, r=Centril
adjust deprecation date of mem::uninitialized
In https://github.com/rust-lang/rust/pull/60445 we [decided](https://github.com/rust-lang/rust/pull/60445#issuecomment-488626308) that we'd deprecate for 1.38 instead of 1.40, but I forgot to adjust for that.
Rollup merge of #60995 - topecongiro:parser-from-stream-and-base-dir, r=michaelwoerister
Add stream_to_parser_with_base_dir
This PR adds `stream_to_parser_with_base_dir`, which creates a parser from a token stream and a base directory.
Context: I would like to parse `cfg_if!` macro and get a list of modules defined inside it from rustfmt so that rustfmt can format those modules (cc https://github.com/rust-lang/rustfmt/issues/3253). To do so, I need to create a parser from `TokenStream` and set the directory of `Parser` to the same directory as the parent directory of a file which contains `cfg_if!` invocation. AFAIK there is no way to achieve this, and hence this PR.
Alternatively, I could change the visibility of `Parser.directory` from `crate` to `pub` so that the value can be modified after initializing a parser. I don't have a preference over either approach (or others, as long as it works).
Rollup merge of #60973 - nnethercote:fix-file_metadata-more, r=michaelwoerister
Avoid symbol interning in `file_metadata`.
This commit changes `created_files` so it uses strings directly as keys,
rather than symbols derived from the strings. This avoids the cost of
having to do the hash table lookups to produce the symbols from the
strings.
The commit also uses `entry` to avoid doing a repeated hash table lookup
(`get` + `insert`).
Note that PR #60467 improved this code somewhat; this is a further
improvement.
Rollup merge of #60963 - blkerby:boxed_docs, r=alexcrichton
Update boxed::Box docs on memory layout
The existing docs for the `Box` type state that "the way `Box` allocates and releases memory is unspecified", and that therefore the only valid pointer to pass to `Box::from_raw` is one obtained from `Box::into_raw`. This is inconsistent with the module-level docs which specify,
> It is valid to convert both ways between a Box and a raw pointer allocated with the Global allocator, given that the Layout used with the allocator is correct for the type. More precisely, a value: *mut T that has been allocated with the Global allocator with Layout::for_value(&*value) may be converted into a box using Box::<T>::from_raw(value). Conversely, the memory backing a value: *mut T obtained from Box::<T>::into_raw may be deallocated using the Global allocator with Layout::for_value(&*value).
This pull request updates the docs for `Box` to make them consistent with the module-level docs and adds some examples of how to use the global allocator in conjunction with `Box::from_raw` and `Box::into_raw`.
bors [Tue, 21 May 2019 21:37:41 +0000 (21:37 +0000)]
Auto merge of #61007 - michaelwoerister:limited-debuginfo, r=alexcrichton
debuginfo: Revert to old/more verbose behavior for -Cdebuginfo=1
https://github.com/rust-lang/rust/commit/cff075009 made LLVM emit less debuginfo when compiling with "line-tables-only". The change was essentially correct but the reduced amount of debuginfo broke
a number of tools.
This commit reverts the change so we get back the old behavior, until we figure out how to do this properly and give external tools to adapt to the new format.
See https://github.com/rust-lang/rust/issues/60020 for more info.
debuginfo: Revert to old/more verbose behavior for -Cdebuginfo=1.
https://github.com/rust-lang/rust/commit/cff075009 made LLVM emit
less debuginfo when compiling with "line-tables-only". The change
was essentially correct but the reduced amount of debuginfo broke
a number of tools.
This commit reverts the change so we get back the old behavior,
until we figure out how to do this properly and give external
tools to adapt to the new format.
See https://github.com/rust-lang/rust/issues/60020 for more info.
bors [Tue, 21 May 2019 00:50:12 +0000 (00:50 +0000)]
Auto merge of #60985 - cr1901:msp430-fix, r=alexcrichton
Bump LLVM submodule to fix MSP430 AsmPrinter and assembler syntax mismatch.
Moving on to steps 9 and 10 of the llvm bugfix [guide](https://rust-lang.github.io/rustc-guide/codegen/updating-llvm.html#bugfix-updates), now that Rust's copy of LLVM was [updated](https://github.com/rust-lang/llvm-project/pull/13).
This PR closes issue #59077. Nightlies following this PR should have working msp430 codegen again :D.
Thanks for the prompt response even though it took me a while to get this "simple" PR done!
Rollup merge of #60983 - petrhosek:libunwind-no-exceptions, r=alexcrichton
Set -funwind-tables and -fno-exceptions unconditionally for LLVM's libunwind
These are required otherwise libunwind will end up with undefined
references to __gxx_personality_v0 which is provided by C++ ABI
library and that's undesirable.
Rollup merge of #60972 - RalfJung:volatile, r=alexcrichton
remove confusing remarks about mixed volatile and non-volatile accesses
These comments were originally added by @ecstatic-morse in https://github.com/rust-lang/rust/commit/911d35f0bfd207112806eaec2763201dad06d1c7 and then later edited by me. The intention, I think, was to make sure people do both their reads and writes with these methods if the affected memory really is used for communication with external devices.
However, [people read this as saying that mixed volatile/non-volatile accesses are UB](https://github.com/rust-lang/rust/issues/58599#issuecomment-493791130), which -- to my knowledge -- they are not. So better remove this.
I went into some detail on the time complexity of `push` because it is relevant for using BinaryHeap efficiently -- specifically that you should avoid pushing many elements in ascending order when possible.
Rollup merge of #60915 - michaelwoerister:hashstablestuff, r=estebank
stable hashing: Remove unused field and add documentation.
This PR removes the `bytes_hashed` field from `StableHasher` which in the past has been used for collecting some statistics but has gone unused for quite a while (months at least) now.
The PR also tries to document some requirements for `HashStable` implementations that haven't been written down explicitly anywhere.
Rollup merge of #60511 - taiki-e:libstd-intra-doc, r=Dylan-DPC
Fix intra-doc link resolution failure on re-exporting libstd
Currently, re-exporting libstd items as below will [occur a lot of failures](https://gist.github.com/taiki-e/e33e0e8631ef47f65a74a3b69f456366).
```rust
pub use std::*;
```
Until the underlying issue (#56922) fixed, we can fix that so they don't propagate to downstream crates.
Related: https://github.com/rust-lang/rust/pull/56941 (That PR fixed failures that occur when re-exporting from libcore to libstd.)
Petr Hosek [Mon, 20 May 2019 19:27:15 +0000 (12:27 -0700)]
Set -funwind-tables and -fno-exceptions unconditionally for LLVM's libunwind
These are required otherwise libunwind will end up with undefined
references to __gxx_personality_v0 which is provided by C++ ABI
library and that's undesirable.
bors [Mon, 20 May 2019 15:05:04 +0000 (15:05 +0000)]
Auto merge of #60445 - RalfJung:maybe-uninit, r=Centril
stabilize core parts of MaybeUninit
and deprecate mem::uninitialized in the future (1.40.0). This is part of implementing https://github.com/rust-lang/rfcs/pull/1892.
Also expand the documentation a bit.
This type is currently primarily useful when dealing with partially initialized arrays. In libstd, it is used e.g. in `BTreeMap` (with some unstable APIs that however can all be replaced, less ergonomically, by stable ones). What we stabilize should also be enough for `SmallVec` (Cc @bluss).
Making this useful for structs requires https://github.com/rust-lang/rfcs/pull/2582 or a commitment that references to uninitialized data are not insta-UB.
This commit changes `created_files` so it uses strings directly as keys,
rather than symbols derived from the strings. This avoids the cost of
having to do the hash table lookups to produce the symbols from the
strings.
The commit also uses `entry` to avoid doing a repeated hash table lookup
(`get` + `insert`).
Note that PR #60467 improved this code somewhat; this is a further
improvement.