Introduce an attribute @_disfavoredOverload that can be used to state
that a particular declaration should be avoided if there is a
successful type-check for a non-@_disfavoredOverload. It's a way to
nudge overload resolution away from particular solutions.
When printing a swiftinterface, represent opaque result types using an attribute that refers to
the mangled name of the defining decl for the opaque type. To turn this back into a reference
to the right decl's implicit OpaqueTypeDecl, use type reconstruction. Since type reconstruction
doesn't normally concern itself with non-type decls, set up a lookup table in SourceFiles and
ModuleFiles to let us handle the mapping from mangled name to opaque type decl in type
reconstruction.
(Since we're invoking type reconstruction during type checking, when the module hasn't yet been
fully validated, we need to plumb a LazyResolver into the ASTBuilder in an unsightly way. Maybe
there's a better way to do this... Longer term, at least, this surface design gives space for
doing things more the right way--a more request-ified decl validator ought to be able to naturally
lazily service this request without the LazyResolver reference, and if type reconstruction in
the future learns how to reconstruct non-type decls, then the lookup tables can go away.)
This is an attribute that gets put on an import in library FooKit to
keep it from being a requirement to import FooKit. It's not checked at
all, meaning that in this form it is up to the author of FooKit to
make sure nothing in its API or ABI depends on the implementation-only
dependency. There's also no debugging support here (debugging FooKit
/should/ import the implementation-only dependency if it's present).
The goal is to get to a point where it /can/ be checked, i.e. FooKit
developers are prevented from writing code that would rely on FooKit's
implementation-only dependency being present when compiling clients of
FooKit. But right now it's not.
rdar://problem/48985979
This is like '@inlinable', except that the symbol does not have a public
entry point in the generated binary at all; it is deserialized and a copy
is always emitted into the client binary, with shared linkage.
Just like '@inlinable', if you apply this to an internal declaration it
becomes '@usableFromInline' automatically.
This uses the same mechanism as default arguments ever since Swift 4, so
it should work reasonably well, but there are rough edges with diagnostics
and such. Don't use this if you are not the standard library.
Fixes <rdar://problem/33767512>, <https://bugs.swift.org/browse/SR-5646>.
Previously we only permitted it on the accessor itself, but there is
no reason not to allow it on the storage declaration.
Fixes <https://bugs.swift.org/browse/SR-3624> / <rdar://problem/31865137>.
* Implement dynamically callable types (`@dynamicCallable`).
- Implement dynamically callable types as proposed in SE-0216.
- Dynamic calls are resolved based on call-site syntax.
- Use the `withArguments:` method if it's defined and there are no
keyword arguments.
- Otherwise, use the `withKeywordArguments:` method.
- Support multiple `dynamicallyCall` methods.
- This enables two scenarios:
- Overloaded `dynamicallyCall` methods on a single
`@dynamicCallable` type.
- Multiple `dynamicallyCall` methods from a `@dynamicCallable`
superclass or from `@dynamicCallable` protocols.
- Add `DynamicCallableApplicableFunction` constraint. This, used with
an overload set, is necessary to support multiple `dynamicallyCall`
methods.
A module compiled with `-enable-private-imports` allows other modules to
import private declarations if the importing source file uses an
``@_private(from: "SourceFile.swift") import statement.
rdar://29318654
Dynamic replacements are currently written in extensions as
extension ExtendedType {
@_dynamicReplacement(for: replacedFun())
func replacement() { }
}
The runtime implementation allows an implementation in the future where
dynamic replacements are gather in a scope and can be dynamically
enabled and disabled.
For example:
dynamic_extension_scope CollectionOfReplacements {
extension ExtentedType {
func replacedFun() {}
}
extension ExtentedType2 {
func replacedFun() {}
}
}
CollectionOfReplacements.enable()
CollectionOfReplacements.disable()
Get the attribute working for more link entity kinds, which addresses
all the FIXME:s in the original test case.
Now the protocol resilience tests can be updated to use @_weakLinked
for all newly-added protocol requirements and default implementations.
This allows the tests to pass in the backward deployment test scenario
as well.
Eventually this will be based on availability instead of a special
attribute.
This completes <rdar://problem/29888071>.
@_nonoverride is the opposite of override, disabling all override checking
for the given declaration. This can be used to suppress diagnostics related
to declarations that are almost overrides but shouldn’t be or to
intentionally break the override chain; in each case, we’ll end up with
an overload rather than an override.
The information about whether a variable/property is initialized is lost in the
public interface, but is, unfortunately, required because it results in a symbol
for the initializer (if a class/struct `init` is inlined, it will call
initializers for properties that it doesn't initialize itself). This is
important to preserve for TBD file generation.
Using an attribute rather than just a bit on the VarDecl means this fits into
the scheme for module interfaces: textual/valid Swift.
This allows us to filter them out in cases that would otherwise be
ambiguous. The particular prompting situation looks a lot like the
test case: a protocol, plus a forward-declared class with the same
name. (Normally we ignore forward-declared classes, but SourceKit's
module interface generation feature makes dummy ClassDecls for them
instead.)
https://bugs.swift.org/browse/SR-4851
The only part of rdar://problem/32722385 I'm going to land in
swift-4.2-branch. This will allow code to be written which
type checks with both 4.2 and a future release of Swift where
a full fix for rdar://problem/32722385 is in place.
@effects is too low a level, and not meant for general usage outside
the standard library. Therefore it deserves to be underscored like
other such attributes.
This reverts commit bb16ee049d,
reversing changes made to a8d831f5f5.
It's not sufficient to solve the problem, and the choices were to do
something more complicated, or just take a simple brute force
approach. We're going with the latter.
1) Formalize "OnAccessor". A hack used to alias this to "OnFunc".
2) New aggregates: OnNominalType, OnGenericType, OnAbstractFunction.
3) Consistent and self-documented (albeit custom) style to ease code review/audits.
4) Removes a few cases of `OnAccessor` based on pull request #16031 feedback.
In theory there could be a "fixed-layout" enum that's not exhaustive
but promises not to add any more cases with payloads, but we don't
need that distinction today.
(Note that @objc enums are still "fixed-layout" in the actual sense of
"having a compile-time known layout". There's just no special way to
spell that.)
(currently spelled with an underscore to indicate its WIP state)
Later commits will handle imported enums correctly and implement the
checks for switch cases.
This is mostly intended to be used for testing at this point; in the
long run, we want to be using availability information to decide
whether to weak-link something or not. You'll notice a bunch of FIXMEs
in the test case that we may not need now, but will probably need to
handle in the future.
Groundwork for doing backward-deployment execution tests.
* Implement the recently accepted SE-0195 proposal, which introduces "Dynamic
Member Lookup" Types. This is a dusted off and updated version of PR13361,
which switches from DynamicMemberLookupProtocol to @dynamicMemberLookup as
was requested by the final review decision. This also rebases it,
updates it for other changes in the compiler, fixes a bunch of bugs, and adds support for keypaths.
Thank you to @rudx and @DougGregor in particular for the helpful review comments and test cases!
...rather than the ad hoc CustomTypeNameManglingAttr I was using
before. As John pointed out, the AST should be semantic wherever
possible.
We may someday want to get out of this being an attribute altogether,
or duplicating information that's available in the original Clang
node, by actually storing a reference to that node somewhere. This is
tricky and mixed up with deciding what hasClangNode() or
getClangDecl() would mean, though, so for now the attribute just
carries the information we need.
When importing a C enum with the ns_error_domain attribute, we
synthesize a struct containing an NSError object to represent errors
in that domain. That synthesized struct should have a mangled name
that ties it to the original C enum, if we want it to be stable, and
now it does.
Before: $SSC7MyErrorV (a normal struct, which is a lie)
After: $SSC11MyErrorCode13ns_error_enumLLV
kind=Global
kind=Structure
kind=Module, text="__C_Synthesized"
kind=PrivateDeclName
kind=Identifier, text="ns_error_enum"
kind=Identifier, text="MyErrorCode"
Using the "private discriminator" feature allows us to pack in extra
information about the declaration without changing the mangling
grammar, and without stepping on anything the importer is using.
More rdar://problem/24688918
For now these are underscored attributes, i.e. compiler internal attributes:
@_optimize(speed)
@_optimize(size)
@_optimize(none)
Those attributes override the command-line specified optimization mode for a specific function.
The @_optimize(none) attribute is equivalent to the already existing @_semantics("optimize.sil.never") attribute
Attach this attribute to VarDecls declared as IUO, and to function decls
that have a result type that is an IUO.
NFC at the moment. Eventually we'll use these to determine where to
implicitly unwrap optional values.
