If the extension adds conformance to an invertible protocol, it's
confusing for people to also infer conditional requirements on the
generic parameters for those invertible protocols. This came up in the
review of SE-427.
Allow lifetime depenendence on types that are BitwiseCopyable & Escapable.
This is unsafe in the sense that the compiler will not diagnose any use of the
dependent value outside of the lexcial scope of the source value. But, in
practice, dependence on an UnsafePointer is often needed. In that case, the
programmer should have already taken responsibility for ensuring the lifetime of the
pointer over all dependent uses. Typically, an unsafe pointer is valid for the
duration of a closure. Lifetime dependence prevents the dependent value from
being returned by the closure, so common usage is safe by default.
Typical example:
func decode(_ bufferRef: Span<Int>) { /*...*/ }
extension UnsafeBufferPointer {
// The client must ensure the lifetime of the buffer across the invocation of `body`.
// The client must ensure that no code modifies the buffer during the invocation of `body`.
func withUnsafeSpan<Result>(_ body: (Span<Element>) throws -> Result) rethrows -> Result {
// Construct Span using its internal, unsafe API.
try body(Span(unsafePointer: baseAddress!, count: count))
}
}
func decodeArrayAsUBP(array: [Int]) {
array.withUnsafeBufferPointer { buffer in
buffer.withUnsafeSpan {
decode($0)
}
}
}
In the future, we may add SILGen support for tracking the lexical scope of
BitwiseCopyable values. That would allow them to have the same dependence
behavior as other source values.
A few things:
1. Internally except for in the parser and the clang importer, we only represent
'sending'. This means that it will be easy to remove 'transferring' once enough
time has passed.
2. I included a warning that suggested to the user to change 'transferring' ->
'sending'.
3. I duplicated the parsing diagnostics for 'sending' so both will still get
different sets of diagnostics for parsing issues... but anywhere below parsing,
I have just changed 'transferring' to 'sending' since transferring isn't
represented at those lower levels.
4. Since SendingArgsAndResults is always enabled when TransferringArgsAndResults
is enabled (NOTE not vis-a-versa), we know that we can always parse sending. So
we import "transferring" as "sending". This means that even if one marks a
function with "transferring", the compiler will guard it behind a
SendingArgsAndResults -D flag and in the imported header print out sending.
rdar://128216574
Pitch - https://github.com/apple/swift-evolution/pull/2305
Changes highlights:
dependsOn(paramName) and dependsOn(scoped argName) syntax
dependsOn(paramName) -> copy lifetime dependence for all parameters/self except
when we have Escapable parameters/self, we assign scope
lifetime dependence.
Allow lifetime dependence on parameters without ownership modifier.
Always infer copy lifetime dependence except when we have
Escapable parameters/self, we infer scope lifetime dependence.
Allow lifetime dependence inference on parameters without ownership modifier.
Protocols with a superclass bound written as `protocol P where Self: C`
return null from getSuperclass(). Unqualified lookup only cares about
getSuperclassDecl(), so serialize that instead.
Fixes rdar://problem/124478687.
These tests were not updated in the transition to
`REQUIRES: noncopyable_generics` and thus running them with a
correctly-built stdlib that has the Copyable requirements.
A swiftmodule can only be correctly ingested by a compiler
that has a matching state of using or not-using
NoncopyableGenerics.
The reason for this is fundamental: the absence of a Copyable
conformance in the swiftmodule indicates that a type is
noncopyable. Thus, if a compiler with NoncopyableGenerics
reads a swiftmodule that was not compiled with that feature,
it will think every type in that module is noncopyable.
Similarly, if a compiler with NoncopyableGenerics produces a
swiftmodule, there will be Copyable requirements on each
generic parameter that the compiler without the feature will
become confused about.
The solution here is to trigger a module mismatch, so that
the compiler re-generates the swiftmodule file using the
swiftinterface, which has been kept compatible with the compiler
regardless of whether the feature is enabled.
Optionally, the dependency to the initialization of the global can be specified with a dependency token `depends_on <token>`.
This is usually a `builtin "once"` which calls the initializer for the global variable.
* `alloc_vector`: allocates an uninitialized vector of elements on the stack or in a statically initialized global
* `vector`: creates an initialized vector in a statically initialized global
Add the thrown type into the AST representation of function types,
mapping from function type representations and declarations into the
appropriate thrown type. Add tests for serialization, printing, and
basic equivalence of function types that have thrown errors.
This instructions marks the point where all let-fields of a class are initialized.
This is important to ensure the correctness of ``ref_element_addr [immutable]`` for let-fields,
because in the initializer of a class, its let-fields are not immutable, yet.
Codegen is the same, but `begin_dealloc_ref` consumes the operand and produces a new SSA value.
This cleanly splits the liferange to the region before and within the destructor of a class.
The diagnostics/remarks out of the ModularizationError wrapped in a
TypeError (eg. coming from resolveCrossReference) is otherwise just
dropped but could help better understand C/C++ interop issues.
It is necessary for opaque values where for casts that will newly start
out as checked_cast_brs and be lowered to checked_cast_addr_brs, since
the latter has the source formal type, IRGen relies on being able to
access it, and there's no way in general to obtain the source formal
type from the source lowered type.
The `bare` attribute indicates that the object header is not used throughout the lifetime of the value.
This means, no reference counting operations are performed on the object and its metadata is not used.
The header of bare objects doesn't need to be initialized.
The `bare` attribute indicates that the object header is not used throughout the lifetime of the object.
This means, no reference counting operations are performed on the object and its metadata is not used.
The header of bare objects doesn't need to be initialized.
Previously we were using the same set of conditions
for serializing as for swiftdoc, so excluded them.
However it's reasonable to have them in the
swiftsourceinfo.
Parse compound and special names in the macro role attributes
(`@freestanding` and `@attached`). This allows both compound names and
initializers, e.g., `init(coding:)`.
Fixes rdar://107967344.
SE-0382 allows macro parameters to have default arguments. Enable these
default arguments, with the normal type checking rules. One
significant quirk to this implementation is that the actual default
argument values don't make it to the macro implementation. This is a
previously-unconsidered design problem we'll need to address.
Tracked by rdar://104043987.
Check accessibility of all build{Partial}Block overloads and
diagnose if none of them are as accessible as type, otherwise
swift interfaces could end up with invalid result builder
declarations when type is public and all builder methods are
internal.
Resolves: rdar://104384604
We want to ensure that the deserialization error added
for this test doesn't trigger when the moveonly type
is not used by the importing module.
part of rdar://106262652