Implement the @export(implementation) and @export(interface) attributes
to replace @_alwaysEmitIntoClient and @_neverEmitIntoClient. Provide a
warning + Fix-It to start staging out the very-new
@_neverEmitIntoClient. We'll hold off on pushing folks toward
@_alwaysEmitIntoClient for a little longer.
Allow external declaration of global variables via `@_extern(c)`. Such
variables need to have types represented in C (of course), have only
storage (no accessors), and cannot have initializers. At the SIL
level, we use the SIL asmname attribute to get the appropriate C name.
While here, slightly shore up the `@_extern(c)` checking, which should
fix issue #70776 / rdar://153515764.
`anyAppleOS` represents a meta-platform for availability checks that can be
used to check availability across all of Apple's operating systems. It
supports versions 26.0 and up since version 26.0 is the first OS version number
that is aligned accross macOS, iOS, watchOS, tvOS, and visionOS.
Apple platform-specific availability specification take precedence over
`anyAppleOS` availability specifications when specified simultaneously.
Resolves rdar://153834380.
Removes the underscored prefixes from the @_section and @_used attributes, making them public as @section and @used respectively. The SymbolLinkageMarkers experimental feature has been removed as these attributes are now part of the standard language. Implemented expression syntactic checking rules per SE-0492.
Major parts:
- Renamed @_section to @section and @_used to @used
- Removed the SymbolLinkageMarkers experimental feature
- Added parsing support for the old underscored names with deprecation warnings
- Updated all tests and examples to use the new attribute names
- Added syntactic validation for @section to align with SE-0492 (reusing the legality checker by @artemcm)
- Changed @DebugDescription macro to explicitly use a tuple type instead of type inferring it, to comply with the expression syntax rules
- Added a testcase for the various allowed and disallowed syntactic forms, `test/ConstValues/SectionSyntactic.swift`.
This experimental feature will be used to force the compiler to treat `Swift`
runtime availability as separate from platform availability when compiling for
targets that have the Swift runtime built-in.
Add support for the `Swift` availability domain, which represents availability
with respect to the Swift runtime. Use of this domain is restricted by the
experimental feature `SwiftRuntimeAvailability`.
This helps avoid producing more downstream errors. This changes
`GenericSignature::forInvalid` to produce the same signature as e.g
`<T where T == Undefined>`. This subsumes the need to introduce
conformance requirements for invertible protocols.
These are tests that fail in the next commit without this flag. This
does not add -verify-ignore-unrelated to all tests with -verify, only
the ones that would fail without it. This is NFC since this flag is
currently a no-op.
An always enabled availability domain is implicitly available in all contexts,
so uses of declarations that are marked as `@available` in the domain are never
rejected. This is useful for an availability domain representing a feature flag
that has become permanently enabled.
Partially resolves rdar://157593409.
This can help work around problems when the names of a C++ declaration
and a Swift declaration would collide, or to temporarily work around
compiler bugs.
rdar://152838988&140802127&158843666
It must be possible to disambiguate overloads using the module-wide Swift
language version, even in contexts that are themselves obsolete in the current
Swift language version.
Resolves rdar://158620835.
The adjusted access level for the subscript shouldn't be fixed automatically
since sometimes the diagnostic is a warning and other times automatically
applying the fix-it immediately causes other errors, which can be confusing.
Resolves rdar://158261884.
Correct several behaviors of availability checking in unavailable contexts that
were inconsistent with the checking model:
- Avoid diagnosing unintroduced and obsolted declarations in contexts that are
unavailable in the same domain.
- Diagnose unavailability normally in type signature contexts.
Set an upper bound on the number of chained lookups we attempt to
avoid spinning while trying to recursively apply the same dynamic
member lookup to itself.
rdar://157288911
Since this is a source breaking change, downgrade the diagnostic to a warning
until the next language version unless library evolution is enabled, in which
case this would have resulted in a broken `.swiftinterface` and it therefore
makes sense to diagnose eagerly.
Resolves rdar://156919010.
Use these queries to replace some duplicated code. Also, move the
`attr_inlinable_available.swift` test to the `Availability` sub-directory since
the test has more to do with availability checking than it has to do
specifically with the `@inlinable` attr.
The present approach is not prudent because `@concurrent` synchronous
functions, a natural extension, are a likely-to-happen future direction,
whereas the current inference rule is entirely grounded on `@concurrent`
being exclusive to async functions.
If we were to ship this rule, we would have to keep the promise for
backwards compatibility when implementing the aforementioned future
direction, replacing one inconsistency with another, and possibly
introducing new bug-prone expression checking code.
```swift
func foo(_: () -> Void) {}
func foo(_: () async -> Void) {}
// In a future without this change and `@concurrent` synchronous
// functions accepted, the first call resolves to the first overload,
// and the second call resolves to the second, despite `@concurrent` no
// longer implying `async`.
foo { }
foo { @concurrent in }
```
This change also drops the fix-it for removing `@concurrent` when used
on a synchronous closure. With the inference rule gone, and the
diagnosis delayed until after solution application, this error raises a
fairly balanced choice between removing the attribute and being
explicit about the effect, where a unilateral suggestion is quite
possibly more harmful than useful.
