special-case #[derive(Copy, Clone)] with a shallow clone
If a type is Copy then its Clone implementation can be a no-op. Currently `#[derive(Clone)]` generates a deep clone anyway. This can lead to lots of code bloat.
This PR detects the case where Copy and Clone are both being derived (the general case of "is this type Copy" can't be determined by a syntax extension) and generates the shallow Clone impl. Right now this can only be done if there are no type parameters (see https://github.com/rust-lang/rust/issues/31085#issuecomment-178988663), but this restriction can be removed after specialization.
Fixes#31085.
Changes #[derive(Copy, Clone)] to use a faster impl of Clone when
both derives are present, and there are no generics in the type.
The faster impl is simply returning *self (which works because the
type is also Copy). See the comments in libsyntax_ext/deriving/clone.rs
for more details.
There are a few types which are Copy but not Clone, in violation
of the definition of Copy. These include large arrays and tuples. The
very existence of these types is arguably a bug, but in order for this
optimization not to change the applicability of #[derive(Copy, Clone)],
the faster Clone impl also injects calls to a new function,
core::clone::assert_receiver_is_clone, to verify that all members are
actually Clone.
This is not a breaking change, because pursuant to RFC 1521, any type
that implements Copy should not do any observable work in its Clone
impl.
Suppress fallback and ambiguity errors
If the infcx has observed other errors, then suppress both default type
parameter fallback (which can be unreliable, as the full constraint set
is not available) and errors related to unresovled
variables (annoyingly, integer type variables cannot currently be
unified with error, so that has to be a separate mechanism). Also add a
flag to `infcx` to allow us to independently indicate when we have
observed an error and hence should trigger this suppression mode.
Fixes#31997
cc @alexcrichton
r? @arielb1
syntax: Merge PathParsingMode::NoTypesAllowed and PathParsingMode::ImportPrefix
syntax: Rename PathParsingMode and its variants to better express their purpose
syntax: Remove obsolete error message about 'self lifetime
syntax: Remove ALLOW_MODULE_PATHS workaround
syntax/resolve: Adjust some error messages
resolve: Compare unhygienic (not renamed) names with keywords::Invalid, invalid identifiers may appear to be valid after renaming
This pass was supposed to check use of gated features before
`#[cfg]`-stripping but this was not the case since it in fact happens
after. Checks that are actually important and must be done before macro
expansion are now made where the features are actually used. Close#32648.
Also ensure that attributes on macro-generated macro invocations are
checked as well. Close#32782 and #32655.
This uncovered a lot of bugs in compiletest and also some shortcomings
of our existing JSON output. We had to add information to the JSON
output, such as suggested text and macro backtraces. We also had to fix
various bugs in the existing tests.
Joint work with jntrnr.
This commit adds support in rustbuild for running all of the compiletest test
suites as part of `make check`. The `compiletest` program was moved to
`src/tools` (like `rustbook` and others) and is now just compiled like any other
old tool. Each test suite has a pretty standard set of dependencies and just
tweaks various parameters to the final compiletest executable.
Note that full support is lacking in terms of:
* Once a test suite has passed, that's not remembered. When a test suite is
requested to be run, it's always run.
* The arguments to compiletest probably don't work for every possible
combination of platforms and testing environments just yet. There will likely
need to be future updates to tweak various pieces here and there.
* Cross compiled test suites probably don't work just yet, support for that will
come in a follow-up patch.
Implement `pub(restricted)` privacy (RFC 1422)
This implements `pub(restricted)` privacy from RFC 1422 (cc #32409) behind a feature gate.
`pub(restricted)` paths currently cannot use re-exported modules both for simplicity of implementation and for future compatibility with RFC 1560 (cf #31783).
r? @nikomatsakis
Fix macro hygiene bug
This fixes#32922 (EDIT: and fixes#31856), macro hygiene bugs.
It is a [breaking-change]. For example, the following would break:
```rust
fn main() {
let x = true;
macro_rules! foo { () => {
let x = 0;
macro_rules! bar { () => {x} }
let _: bool = bar!();
//^ `bar!()` used to resolve the first `x` (a bool),
//| but will now resolve to the second x (an i32).
}}
foo! {};
}
```
r? @nrc
don't report errors in constants at every use site
partially fixes#32842
r? @arielb1
cc @retep998
I chose this way of implementing it, because the alternative (checking if the error span is inside the constant's expressions's span) would get confusing when combined with expression generating macros.
A next step would be to re-enable the re-reporting of errors if the original erroneous constant is in another crate.
Replace consider_unification_despite_ambiguity with new obligation variant
Is work towards #32730. Addresses part one of #32286. Addresses #24210 and #26046 to some degree.
r? @nikomatsakis
resolve: Improve duplicate glob detection
This fixes a bug introduced in #31726 in which we erroneously allow multiple imports of the same item under some circumstances.
More specifically, we erroneously allow a module that is in a cycle of glob re-exports to have other re-exports (besides the glob from the cycle).
For example,
```rust
pub fn f() {}
mod foo {
pub use f; // (1) This defines `foo::f`.
pub use bar::*; // (3) This also defines `foo::f`, which should be a duplicate error but is currently allowed.
}
mod bar {
pub use foo::*; // (2) This defines `bar::f`.
}
```
A module in a glob re-export cycle can still have `pub` items after this PR. For example,
```rust
mod foo {
pub fn f() {}; // (1) This defines `foo::f`.
pub use bar::*; // (3) This is not a duplicate error since items shadow glob-imported re-exports (cf #31337).
}
mod bar {
pub use foo::*; // (2) This defines `bar::f`.
}
```
r? @nikomatsakis
If the infcx has observed other errors, then suppress both default type
parameter fallback (which can be unreliable, as the full constraint set
is not available) and errors related to unresovled
variables (annoyingly, integer type variables cannot currently be
unified with error, so that has to be a separate mechanism). Also add a
flag to `infcx` to allow us to independently indicate when we have
observed an error and hence should trigger this suppression mode.
This commit rewrites all of the tidy checks we have, namely:
* featureck
* errorck
* tidy
* binaries
into Rust under a new `tidy` tool inside of the `src/tools` directory. This at
the same time deletes all the corresponding Python tidy checks so we can be sure
to only have one source of truth for all the tidy checks.
cc #31590
std: Stabilize APIs for the 1.9 release
This commit applies all stabilizations, renamings, and deprecations that the
library team has decided on for the upcoming 1.9 release. All tracking issues
have gone through a cycle-long "final comment period" and the specific APIs
stabilized/deprecated are:
Stable
* `std::panic`
* `std::panic::catch_unwind` (renamed from `recover`)
* `std::panic::resume_unwind` (renamed from `propagate`)
* `std::panic::AssertUnwindSafe` (renamed from `AssertRecoverSafe`)
* `std::panic::UnwindSafe` (renamed from `RecoverSafe`)
* `str::is_char_boundary`
* `<*const T>::as_ref`
* `<*mut T>::as_ref`
* `<*mut T>::as_mut`
* `AsciiExt::make_ascii_uppercase`
* `AsciiExt::make_ascii_lowercase`
* `char::decode_utf16`
* `char::DecodeUtf16`
* `char::DecodeUtf16Error`
* `char::DecodeUtf16Error::unpaired_surrogate`
* `BTreeSet::take`
* `BTreeSet::replace`
* `BTreeSet::get`
* `HashSet::take`
* `HashSet::replace`
* `HashSet::get`
* `OsString::with_capacity`
* `OsString::clear`
* `OsString::capacity`
* `OsString::reserve`
* `OsString::reserve_exact`
* `OsStr::is_empty`
* `OsStr::len`
* `std::os::unix::thread`
* `RawPthread`
* `JoinHandleExt`
* `JoinHandleExt::as_pthread_t`
* `JoinHandleExt::into_pthread_t`
* `HashSet::hasher`
* `HashMap::hasher`
* `CommandExt::exec`
* `File::try_clone`
* `SocketAddr::set_ip`
* `SocketAddr::set_port`
* `SocketAddrV4::set_ip`
* `SocketAddrV4::set_port`
* `SocketAddrV6::set_ip`
* `SocketAddrV6::set_port`
* `SocketAddrV6::set_flowinfo`
* `SocketAddrV6::set_scope_id`
* `<[T]>::copy_from_slice`
* `ptr::read_volatile`
* `ptr::write_volatile`
* The `#[deprecated]` attribute
* `OpenOptions::create_new`
Deprecated
* `std::raw::Slice` - use raw parts of `slice` module instead
* `std::raw::Repr` - use raw parts of `slice` module instead
* `str::char_range_at` - use slicing plus `chars()` plus `len_utf8`
* `str::char_range_at_reverse` - use slicing plus `chars().rev()` plus `len_utf8`
* `str::char_at` - use slicing plus `chars()`
* `str::char_at_reverse` - use slicing plus `chars().rev()`
* `str::slice_shift_char` - use `chars()` plus `Chars::as_str`
* `CommandExt::session_leader` - use `before_exec` instead.
Closes#27719
cc #27751 (deprecating the `Slice` bits)
Closes#27754Closes#27780Closes#27809Closes#27811Closes#27830Closes#28050Closes#29453Closes#29791Closes#29935Closes#30014Closes#30752Closes#31262
cc #31398 (still need to deal with `before_exec`)
Closes#31405Closes#31572Closes#31755Closes#31756
This commit applies all stabilizations, renamings, and deprecations that the
library team has decided on for the upcoming 1.9 release. All tracking issues
have gone through a cycle-long "final comment period" and the specific APIs
stabilized/deprecated are:
Stable
* `std::panic`
* `std::panic::catch_unwind` (renamed from `recover`)
* `std::panic::resume_unwind` (renamed from `propagate`)
* `std::panic::AssertUnwindSafe` (renamed from `AssertRecoverSafe`)
* `std::panic::UnwindSafe` (renamed from `RecoverSafe`)
* `str::is_char_boundary`
* `<*const T>::as_ref`
* `<*mut T>::as_ref`
* `<*mut T>::as_mut`
* `AsciiExt::make_ascii_uppercase`
* `AsciiExt::make_ascii_lowercase`
* `char::decode_utf16`
* `char::DecodeUtf16`
* `char::DecodeUtf16Error`
* `char::DecodeUtf16Error::unpaired_surrogate`
* `BTreeSet::take`
* `BTreeSet::replace`
* `BTreeSet::get`
* `HashSet::take`
* `HashSet::replace`
* `HashSet::get`
* `OsString::with_capacity`
* `OsString::clear`
* `OsString::capacity`
* `OsString::reserve`
* `OsString::reserve_exact`
* `OsStr::is_empty`
* `OsStr::len`
* `std::os::unix::thread`
* `RawPthread`
* `JoinHandleExt`
* `JoinHandleExt::as_pthread_t`
* `JoinHandleExt::into_pthread_t`
* `HashSet::hasher`
* `HashMap::hasher`
* `CommandExt::exec`
* `File::try_clone`
* `SocketAddr::set_ip`
* `SocketAddr::set_port`
* `SocketAddrV4::set_ip`
* `SocketAddrV4::set_port`
* `SocketAddrV6::set_ip`
* `SocketAddrV6::set_port`
* `SocketAddrV6::set_flowinfo`
* `SocketAddrV6::set_scope_id`
* `<[T]>::copy_from_slice`
* `ptr::read_volatile`
* `ptr::write_volatile`
* The `#[deprecated]` attribute
* `OpenOptions::create_new`
Deprecated
* `std::raw::Slice` - use raw parts of `slice` module instead
* `std::raw::Repr` - use raw parts of `slice` module instead
* `str::char_range_at` - use slicing plus `chars()` plus `len_utf8`
* `str::char_range_at_reverse` - use slicing plus `chars().rev()` plus `len_utf8`
* `str::char_at` - use slicing plus `chars()`
* `str::char_at_reverse` - use slicing plus `chars().rev()`
* `str::slice_shift_char` - use `chars()` plus `Chars::as_str`
* `CommandExt::session_leader` - use `before_exec` instead.
Closes#27719
cc #27751 (deprecating the `Slice` bits)
Closes#27754Closes#27780Closes#27809Closes#27811Closes#27830Closes#28050Closes#29453Closes#29791Closes#29935Closes#30014Closes#30752Closes#31262
cc #31398 (still need to deal with `before_exec`)
Closes#31405Closes#31572Closes#31755Closes#31756
Save/load incremental compilation dep graph
Contains the code to serialize/deserialize the dep graph to disk between executions. We also hash the item contents and compare to the new hashes. Also includes a unit test harness. There are definitely some known limitations, such as https://github.com/rust-lang/rust/issues/32014 and https://github.com/rust-lang/rust/issues/32015, but I am leaving those for follow-up work.
Note that this PR builds on https://github.com/rust-lang/rust/pull/32007, so the overlapping commits can be excluded from review.
r? @michaelwoerister
Lay groundwork for RFC 1422 and improve `PrivateItemsInPublicInterfacesVisitor`
This PR lays groundwork for RFC 1422 (cc #32409) and improves `PrivateItemsInPublicInterfacesVisitor`. More specifically, it
- Refactors away `hir::Visibility::inherit_from`, the semantics of which are obsolete.
- Makes `hir::Visibility` non-`Copy` so that we will be able to add new variants to represent `pub(restricted)` (for example, `Visibility::Restricted(Path)`).
- Adds a new `Copy` type `ty::Visibility` that represents a visibility value, i.e. a characterization of where an item is accessible. This is able to represent `pub(restricted)` visibilities.
- Improves `PrivateItemsInPublicInterfacesVisitor` so that it checks for items in an interface that are less visible than the interface. This fixes#30079 but doesn't change any other behavior.
r? @nikomatsakis
Suggest adding a where-clause when that can help
Suggest adding a where-clause when there is an unmet trait-bound that can be satisfied if some type can implement it.
r? @nikomatsakis
Fix LLVM assert when handling bad intrinsic monomorphizations
Passing an invalid type to certain intrinsics would trigger an LLVM assert even though the invalid type was caught by the compiler.
r? @eddyb
You can now pass `-Z incremental=dir` as well as saying `-Z
query-dep-graph` if you want to enable queries for some other
purpose. Accessor functions take the place of computed boolean flags.
Fix "consider removing this semicolon" help
Check last statement in a block, not the first.
Example of current weirdness: http://is.gd/w80J9h
The help was only rarely emitted, and if so, often incorrectly (see above playpen). It was basically only useful with single-statement functions.
Fix issue: Global paths in `use` directives can begin with `super` or `self` #32225
This PR fixes#32225 by warning on `use ::super::...` and `use ::self::...` on `resolve`.
Current changes is the most minimal and ad-hoc.
resolve: Improve import failure detection and lay groundwork for RFC 1422
This PR improves import failure detection and lays some groundwork for RFC 1422.
More specifically, it
- Avoids recomputing the resolution of an import directive's module path.
- Refactors code in `resolve_imports` that does not scale to the arbitrarily many levels of visibility that will be required by RFC 1422.
- Replaces `ModuleS`'s fields `public_glob_count`, `private_glob_count`, and `resolved_globs` with a list of glob import directives `globs`.
- Replaces `NameResolution`'s fields `pub_outstanding_references` and `outstanding_references` with a field `single_imports` of a newly defined type `SingleImports`.
- Improves import failure detection by detecting cycles that include single imports (currently, only cycles of globs are detected). This fixes#32119.
r? @nikomatsakis
Only allow using the atomic intrinsics on integer types
Using these with non-integer types results in LLVM asserts. Atomic operations on non-integer types will require values be transmuted into an integer type of suitable size.
This doesn't affect the standard library since `AtomicBool` and `AtomicPtr` currently use `usize` for atomic operations.
r? @eddyb
When deciding on a coinductive match, we were examining the new
obligation and the backtrace, but not the *current* obligation that goes
in between the two. Refactoring the code to just have the cycle given
as input also made things a lot simpler.
Integrate privacy into field and method selection
This PR integrates privacy checking into field and method selection so that an inaccessible field/method can not stop an accessible field/method from being used (fixes#12808 and fixes#22684).
r? @eddyb
diagnostics: make paths to external items more visible
This PR changes the reported path for an external item so that it is visible from at least one local module (i.e. it does not use any inaccessible external modules) if possible. If the external item's crate was declared with an `extern crate`, the path is guarenteed to use the `extern crate`.
Fixes#23224, fixes#23355, fixes#26635, fixes#27165.
r? @nrc
