The main gist of this PR is commit 1077efb which removes the list of supertraits from the `TraitDef` and pulls them into a separate table, which is accessed via `lookup_super_predicates`. This is analogous to `lookup_predicates`, which gets the complete where clause. This allows us to create the `TraitDef`, which contains the list generics and so forth, without fully knowing the list of supertraits. This in turn allows the *supertrait listing* to contain references to associated types like `<Self as Foo>::Item`, which were previously impossible because conversion required having the `TraitDef` for `Foo`.
We do not yet support `Self::Item` in a supertrait listing. This doesn't work because to convert that, it attempts to expand out the full set of supertraits, which are in the process of being created. This could potentially be worked out by having the expansion of supertraits proceed in a lazy fashion, but we'd have to define shadowing rules for associated types which we don't currently have.
Along the way (in 9de9ec5) I also removed the restriction against duplicate bounds and generalized the code so that it can handle having the same supertrait multiple times with different arguments, e.g. `Foo : Bar<i32> + Bar<u32>`. This restriction was serving no particular purpose, since the same trait could be extended multiple times indirectly, and in the era of multidispatch it is actively harmful.
This is technically a [breaking-change] because it affects the definition of a super-trait. Anything in a where clause that looks like `where Self : Foo` is now considered a supertrait. Because cycles are disallowed in supertraits, that could lead to some errors. This has not been observed in any existing code.
r? @nrc
Automatic has-same-types testing methodology can be found in #22501.
Because most of them don't work with `--pretty=typed`, compile-fail tests were manually audited.
r? @aturon
This commit deprecates the majority of std::old_io::fs in favor of std::fs and
its new functionality. Some functions remain non-deprecated but are now behind a
feature gate called `old_fs`. These functions will be deprecated once
suitable replacements have been implemented.
The compiler has been migrated to new `std::fs` and `std::path` APIs where
appropriate as part of this change.
Many of the modifications putting in `Box::new` calls also include a
pointer to Issue 22405, which tracks going back to `box <expr>` if
possible in the future.
(Still tried to use `Box<_>` where it sufficed; thus some tests still
have `box_syntax` enabled, as they use a mix of `box` and `Box::new`.)
Precursor for overloaded-`box` and placement-`in`; see Issue 22181.
Rebase and follow-through on work done by @cmr and @aatch.
Implements most of rust-lang/rfcs#560. Errors encountered from the checks during building were fixed.
The checks for division, remainder and bit-shifting have not been implemented yet.
See also PR #20795
cc @Aatch ; cc @nikomatsakis
This changes the type of some public constants/statics in libunicode.
Notably some `&'static &'static [(char, char)]` have changed
to `&'static [(char, char)]`. The regexp crate seems to be the
sole user of these, yet this is technically a [breaking-change]
However, I left the ICEs rather than switching to nicer error
reporting there; these cases *should* be detected prior to hitting
trans, and thus ICE'ing here is appropriate.
(So why switch to `eval_const_expr_partial`? Because I want to try to
eliminate all uses of `eval_const_expr` entirely.)
Adds overflow checking to integer addition, multiplication, and subtraction
when `-Z force-overflow-checks` is true, or if `--cfg ndebug` is not passed to
the compiler. On overflow, it panics with `arithmetic operation overflowed`.
Also adds `overflowing_add`, `overflowing_sub`, and `overflowing_mul`
intrinsics for doing unchecked arithmetic.
[breaking-change]
Remove the synthetic \"region bound\" from closures and instead update how
type-outlives works for closure types so that it ensures that all upvars
outlive the region in question. This gives the same guarantees but
without introducing artificial regions (and gives better error messages
to boot). This is refactoring towards #3696.
r? @pnkfelix
This changes the type of some public constants/statics in libunicode.
Notably some `&'static &'static [(char, char)]` have changed
to `&'static [(char, char)]`. The regexp crate seems to be the
sole user of these, yet this is technically a [breaking-change]
type-outlives works for closure types so that it ensures that all upvars
outlive the region in question. This gives the same guarantees but
without introducing artificial regions (and gives better error messages
to boot).
... objects
For method calls through trait objects, we currently generate the llvm
function argument attributes using the non-opaque method signature that
still has the trait object fat pointer for the self pointer. This leads
to attributes that are plain wrong, e.g. noalias. As we don't know
anything about the concrete type of the underlying object, we must
replace the self argument with an opaque i8 pointer before applying the
attributes.
For method calls through trait objects, we currently generate the llvm
function argument attributes using the non-opaque method signature that
still has the trait object fat pointer for the self pointer. This leads
to attributes that are plain wrong, e.g. noalias. As we don't know
anything about the concrete type of the underlying object, we must
replace the self argument with an opaque i8 pointer before applying the
attributes.
static_assert is documented as working on static with type `bool`, but
we currently accept it on any const static and crash when the const has
an non-integral type.
This is a breaking-change for anyone who used static_assert on types
likes i32, which happened to work but seems like an unintended
consequence of the missing error checking.
[breaking-change]
Fixes#22056
static_assert is documented as working on static with type `bool`, but
we currently accept it on any const static and crash when the const has
an non-integral type.
This is a breaking-change for anyone who used static_assert on types
likes i32, which happened to work but seems like an unintended
consequence of the missing error checking.
[breaking-change]
Fixes#22056
Now that the `std::env` module has had some time to bake this commit marks most
of its APIs as `#[stable]`. Some notable APIs that are **not** stable (and still
use the same `env` feature gate) are:
* `{set,get}_exit_status` - there are still questions about whether this is the
right interface for setting/getting the exit status of a process.
* `page_size` - this may change location in the future or perhaps name as well.
This also effectively closes#22122 as the variants of `VarError` are
`#[stable]` now. (this is done intentionally)
Now that the `std::env` module has had some time to bake this commit marks most
of its APIs as `#[stable]`. Some notable APIs that are **not** stable (and still
use the same `env` feature gate) are:
* `{set,get}_exit_status` - there are still questions about whether this is the
right interface for setting/getting the exit status of a process.
* `page_size` - this may change location in the future or perhaps name as well.
This also effectively closes#22122 as the variants of `VarError` are
`#[stable]` now. (this is done intentionally)
Fixes#22525
I wasn't sure if I should reuse `write::get_llvm_opt_level` or not. It returns an `llvm::CodeGenOptLevel`, which is the Rust binding for `CodeGenOpt::Level`. `lto.rs` is passing an optlevel to LLVM's `PassManagerBuilder`, which takes an unsigned int. `PassManagerBuilder`'s optlevel uses essentially the same enumeration (i.e. 0-3 with 2 as default), but it's implicit.
aatch's cfg revisions, namely to match expressions
Revise handling of match expressions so that arms branch to next arm.
Update the graphviz tests accordingly.
Fixes#22073. (Includes regression test for the issue.)
RFC 817 is not yet accepted, but I wanted to put this code up so people can see how it works. And to be ready lest it should be accepted.
cc rust-lang/rfcs#817
This is one more step towards completing #13231
This series of commits add support for default trait implementations. The changes in this PR don't break existing code and they are expected to preserve the existing behavior in the compiler as far as built-in bounds checks go.
The PR adds negative implementations of `Send`/`Sync` for some types and it removes the special cases for `Send`/`Sync` during the trait obligations checks. That is, it now fully relies on the traits check rather than lang items.
Once this patch lands and a new snapshot is created, it'll be possible to add default impls for `Send` and `Sync` and remove entirely the use of `BuiltinBound::{BoundSend,BoundSync}` for positive implementations as well.
This PR also removes the restriction on negative implementations. That is, it is now possible to add negative implementations for traits other than `Send`/`Sync`
We already do this for the function arguments, but miss it for the
retslot pointer, which can lead to LLVM assertions because the retslot
has the wrong type.
Fixes#22663
We already do this for the function arguments, but miss it for the
retslot pointer, which can lead to LLVM assertions because the retslot
has the wrong type.
Fixes#22663
In `if loop {} {}`, the `if` is actually unreachable, but we didn't
handle that correctly and when trying to translate the `if` we tried to
branch on the \"return value\" of the loop expression, which is not an
`i1` and therefore triggered an LLVM assertion.
In `if loop {} {}`, the `if` is actually unreachable, but we didn't
handle that correctly and when trying to translate the `if` we tried to
branch on the "return value" of the loop expression, which is not an
`i1` and therefore triggered an LLVM assertion.
This commit is an implementation of [RFC 592][r592] and [RFC 840][r840]. These
two RFCs tweak the behavior of `CString` and add a new `CStr` unsized slice type
to the module.
[r592]: https://github.com/rust-lang/rfcs/blob/master/text/0592-c-str-deref.md
[r840]: https://github.com/rust-lang/rfcs/blob/master/text/0840-no-panic-in-c-string.md
The new `CStr` type is only constructable via two methods:
1. By `deref`'ing from a `CString`
2. Unsafely via `CStr::from_ptr`
The purpose of `CStr` is to be an unsized type which is a thin pointer to a
`libc::c_char` (currently it is a fat pointer slice due to implementation
limitations). Strings from C can be safely represented with a `CStr` and an
appropriate lifetime as well. Consumers of `&CString` should now consume `&CStr`
instead to allow producers to pass in C-originating strings instead of just
Rust-allocated strings.
A new constructor was added to `CString`, `new`, which takes `T: IntoBytes`
instead of separate `from_slice` and `from_vec` methods (both have been
deprecated in favor of `new`). The `new` method returns a `Result` instead of
panicking. The error variant contains the relevant information about where the
error happened and bytes (if present). Conversions are provided to the
`io::Error` and `old_io::IoError` types via the `FromError` trait which
translate to `InvalidInput`.
This is a breaking change due to the modification of existing `#[unstable]` APIs
and new deprecation, and more detailed information can be found in the two RFCs.
Notable breakage includes:
* All construction of `CString` now needs to use `new` and handle the outgoing
`Result`.
* Usage of `CString` as a byte slice now explicitly needs a `.as_bytes()` call.
* The `as_slice*` methods have been removed in favor of just having the
`as_bytes*` methods.
Closes#22469Closes#22470
[breaking-change]
This commit is an implementation of [RFC 823][rfc] which is another pass over
the `std::hash` module for stabilization. The contents of the module were not
entirely marked stable, but some portions which remained quite similar to the
previous incarnation are now marked `#[stable]`. Specifically:
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0823-hash-simplification.md
* `std::hash` is now stable (the name)
* `Hash` is now stable
* `Hash::hash` is now stable
* `Hasher` is now stable
* `SipHasher` is now stable
* `SipHasher::new` and `new_with_keys` are now stable
* `Hasher for SipHasher` is now stable
* Many `Hash` implementations are now stable
All other portions of the `hash` module remain `#[unstable]` as they are less
commonly used and were recently redesigned.
This commit is a breaking change due to the modifications to the `std::hash` API
and more details can be found on the [RFC][rfc].
Closes#22467
[breaking-change]
In trans_slice_vec we currently use arrayalloca, which gives us a
pointer to the element type with enough memory allocated for the
requested number of elements. This works, but everywhere else we use
the [n x T] type for fixed size arrays and so we have to bitcast the
pointer here. Let's directly use the proper type for the allocation and
remove some code duplication along the way.
Take 2. This PR includes a bunch of refactoring that was part of an experimental branch implementing [implied bounds]. That particular idea isn't ready to go yet, but the refactoring proved useful for fixing #22246. The implied bounds branch also exposed #22110 so a simple fix for that is included here. I still think some more refactoring would be a good idea here -- in particular I think most of the code in wf.rs is kind of duplicating the logic in implicator and should go, but I decided to post this PR and call it a day before diving into that. I'll write a bit more details about the solutions I adopted in the various bugs. I patched the two issues I was concerned about, which was the handling of supertraits and HRTB (the latter turned out to be fine, so I added a comment explaining why.)
r? @pnkfelix (for now, anyway)
cc @aturon
[implied bounds]: http://smallcultfollowing.com/babysteps/blog/2014/07/06/implied-bounds/
This overlaps with #22276 (I left make check running overnight) but covers a number of additional cases and has a few rewrites where the clones are not even necessary.
This also implements `RandomAccessIterator` for `iter::Cloned`
cc @steveklabnik, you may want to glance at this before #22281 gets the bors treatment
This commit is an implementation of [RFC 592][r592] and [RFC 840][r840]. These
two RFCs tweak the behavior of `CString` and add a new `CStr` unsized slice type
to the module.
[r592]: https://github.com/rust-lang/rfcs/blob/master/text/0592-c-str-deref.md
[r840]: https://github.com/rust-lang/rfcs/blob/master/text/0840-no-panic-in-c-string.md
The new `CStr` type is only constructable via two methods:
1. By `deref`'ing from a `CString`
2. Unsafely via `CStr::from_ptr`
The purpose of `CStr` is to be an unsized type which is a thin pointer to a
`libc::c_char` (currently it is a fat pointer slice due to implementation
limitations). Strings from C can be safely represented with a `CStr` and an
appropriate lifetime as well. Consumers of `&CString` should now consume `&CStr`
instead to allow producers to pass in C-originating strings instead of just
Rust-allocated strings.
A new constructor was added to `CString`, `new`, which takes `T: IntoBytes`
instead of separate `from_slice` and `from_vec` methods (both have been
deprecated in favor of `new`). The `new` method returns a `Result` instead of
panicking. The error variant contains the relevant information about where the
error happened and bytes (if present). Conversions are provided to the
`io::Error` and `old_io::IoError` types via the `FromError` trait which
translate to `InvalidInput`.
This is a breaking change due to the modification of existing `#[unstable]` APIs
and new deprecation, and more detailed information can be found in the two RFCs.
Notable breakage includes:
* All construction of `CString` now needs to use `new` and handle the outgoing
`Result`.
* Usage of `CString` as a byte slice now explicitly needs a `.as_bytes()` call.
* The `as_slice*` methods have been removed in favor of just having the
`as_bytes*` methods.
Closes#22469Closes#22470
[breaking-change]