Map the lifetime dependencies described in terms of the formal AST-level parameters
to the correct parameter(s) in the lowered SIL function type. There can be 0, 1,
or many SIL parameters per formal parameter because of tuple exploding. Also,
record which dependencies are on addressable parameters (meaning that the dependency
includes not only the value of the parameter, but its specific memory location).
Instead of canonicalizing platform versions during parsing and storing two
versions, just canonicalize the parsed version on-demand when its requested.
* Move `AvailabilitySpec` handling logic to AST, so they can be shared
between libParse and ASTGen
* Requestify '-define-availability' arguments parsing and parse them
with 'SwiftParser' according to the 'ParserASTGen' feature flag
* Implement 'AvailableAttr' generation in ASTGen
'ParserUnit' is used for analyzing syntax structures _mainly_ in
SourceKit.
Since we removed IfConfigDecl from AST, ParserUnit didn't
inclue any AST in #if ... #endif regions even for active region because
it used to consider all inactive. Instead, consider every region
"active" and include all the AST nodes.
rdar://117387631
Since resolving the domain of an `@available` attribute is done during type
checking now, diagnostics about unexpected versions for a domain need to be
emitted at that point instead of during parsing. It doesn't make sense to
maintain the special version of this diagnostic that is emitted during parsing
for the universal availability domain only.
Since the domain is now resolved by SemanticAvailableAttrRequest, diagnosing
attributes with invalid combinations of fields for a specific domains needs to
be delayed.
AvailableAttr::Kind and AvailabilityDomain are designed to replace
PlatformAgnosticAvailabilityKind, allowing AvailableAttr to more flexibly model
availability for arbitrary domains. For now, the new constructor just
translates its inputs into inputs for the existing constructor. Once all of the
callers of the existing AvailableAttr constructor have been updated to use the
new constructor, the representation of AvailableAttr will be updated to store
the new properties.
Introduce an `unsafe` expression akin to `try` and `await` that notes
that there are unsafe constructs in the expression to the right-hand
side. Extend the effects checker to also check for unsafety along with
throwing and async operations. This will result in diagnostics like
the following:
10 | func sum() -> Int {
11 | withUnsafeBufferPointer { buffer in
12 | let value = buffer[0]
| | `- note: reference to unsafe subscript 'subscript(_:)'
| |- warning: expression uses unsafe constructs but is not marked with 'unsafe'
| `- note: reference to parameter 'buffer' involves unsafe type 'UnsafeBufferPointer<Int>'
13 | tryWithP(X())
14 | return fastAdd(buffer.baseAddress, buffer.count)
These will come with a Fix-It that inserts `unsafe` into the proper
place. There's also a warning that appears when `unsafe` doesn't cover
any unsafe code, making it easier to clean up extraneous `unsafe`.
This approach requires that `@unsafe` be present on any declaration
that involves unsafe constructs within its signature. Outside of the
signature, the `unsafe` expression is used to identify unsafe code.
There’s a very easy to reach `llvm_unreachable()` in this code which ought to be a diagnostic, as well as a couple of other issues. Rework it into something that’s a bit better at handling the edge cases.
This attribute will allow you to specify an alternate version of the declaration used for mangling. It will allow minor adjustments to be made to declarations so long as they’re still compatible at the calling convention level, such as refining isolation or sendability, renaming without breaking ABI, etc.
The attribute is behind the experimental feature flag `ABIAttribute`.
