This patch re-enables diagnostics for unannotated C++ functions or
methods returning `SWIFT_SHARED_REFERENCE` types. These warnings now
fire only **once per source location**, even in the presence of multiple
template instantiations. This avoids diagnostic duplication that was a
key source of noise in the compilation of larger codebases.
These warnings were previously disabled starting in **Swift 6.2** via
[PR-#81411](https://github.com/swiftlang/swift/pull/81411) due to
concerns around false positives and excessive duplication in projects
adopting C++ interop. This patch addresses the duplication issue by
adding source-location-based caching, which ensures that a warning is
emitted only once per source location, even across template
instantiations with different types.
However, the false positive issue remains to be investigated and will be
addressed in a follow-up patch. Until that happens, the warnings are
gated behind a new experimental feature flag:
`WarnUnannotatedReturnOfCxxFrt`. This feature will be enabled by default
only after thorough qualification and testing on large C++ codebases.
rdar://154261051
Since LayoutPrespecialization has been enabled by default in all compiler
invocations for quite some time, it doesn't make sense for it to be treated as
experimental feature. Make it a baseline feature and remove all the
checks for it from the compiler.
Add an extra opaque field to AddressSpace, which can be used by clients
of RemoteInspection to distinguish between different address spaces.
LLDB employs an optimization where it reads memory from files instead of
the running process whenever it can to speed up memory reads (these can
be slow when debugging something over a network). To do this, it needs
to keep track whether an address originated from a process or a file. It
currently distinguishes addresses by setting an unused high bit on the
address, but because of pointer authentication this is not a reliable
solution. In order to keep this optimization working, this patch adds an
extra opaque AddressSpace field to RemoteAddress, which LLDB can use on
its own implementation of MemoryReader to distinguish between addresses.
This patch is NFC for the other RemoteInspection clients, as it adds
extra information to RemoteAddress, which is entirely optional and if
unused should not change the behavior of the library.
Although this patch is quite big the changes are largely mechanical,
replacing threading StoredPointer with RemoteAddress.
rdar://148361743
This is an accepted spelling for the attribute. This commit
also renames the feature flag from `ExtensibleAttribute` to
`NonexhaustiveAttribute` to match the spelling of the attribute.
Most of the logic for C++ foreign reference types can be applied to C types as well. Swift had a compiler flag `-Xfrontend -experimental-c-foreign-reference-types` for awhile now which enables foreign reference types without having to enable C++ interop. This change makes it the default behavior.
Since we don't expect anyone to pass `experimental-c-foreign-reference-types` currently, this also removes the frontend flag.
rdar://150308819
When the default isolation is main-actor, don't infer @MainActor
for a type that conforms to a protocol P in its primary definition when
P inherits from Sendable. Such types should remain non-isolated
because they're highly unlikely to be able to implement the P
conformance (which cannot be isolated).
Put this feature behind a new experimental flag,
SendableProhibitsMainActorInference.
Implements rdar://151029300
This flag was not experimental for any good reason; it should always be
enabled. The flag only exists so we can introduce a new API:
UnsafeMutablePointer.mutableSpan. Supported compilers cannot handle the new API.
rdar://154247502 (Promote feature NonescapableAccessorOnTrivial to be
non-experimental)
To guard the new UnsafeMutablePointer.mutableSpan APIs.
This allows older compilers to ignore the new APIs. Otherwise, the type checker
will crash on the synthesized _read accessor for a non-Escapable type:
error: cannot infer lifetime dependence on the '_read' accessor because 'self'
is BitwiseCopyable, specify '@lifetime(borrow self)'
I don't know why the _read is synthesized in these cases, but apparently it's
always been that way.
Fixes: rdar://153773093 ([nonescapable] add a compiler feature to guard
~Escapable accessors when self is trivial)
We want to be able to adopt
(https://github.com/swiftlang/swift/pull/82225) in the stdlib without
breaking people building at desk with older toolchains, so let's add a
feature flag.
The concrete nesting limit, which defaults to 30, catches
things like A == G<A>. However, with something like
A == (A, A), you end up with an exponential problem size
before you hit the limit.
Add two new limits.
The first is the total size of the concrete type, counting
all leaves, which defaults to 4000. It can be set with the
-requirement-machine-max-concrete-size= frontend flag.
The second avoids an assertion in addTypeDifference() which
can be hit if a certain counter overflows before any other
limit is breached. This also defaults to 4000 and can be set
with the -requirement-machine-max-type-differences= frontend flag.
Initially, the compiler rejected building dependencies that contained OS
versions in an invalid range. However, this happens to be quite
disruptive, so instead allow it and request that these versions be
implicitly bumped based on what `llvm::Triple::getCanonicalVersionForOS`
computes.
resolves: rdar://153205856
Currently, when we jump-to-definition for decls that are macro-expanded
from Clang imported decls (e.g., safe overloads generated by
@_SwiftifyImport), setLocationInfo() emits a bongus location pointing to
a generated buffer, leading the IDE to try to jump to a file that does
not exist.
The root cause here is that setLocationInfo() calls getOriginalRange()
(earlier, getOriginalLocation()), which was not written to account for
such cases where a macro is generated from another generated buffer
whose kind is 'AttributeFromClang'.
This patch fixes setLocationInfo() with some refactoring:
- getOriginalRange() is inlined into setLocationInfo(), so that the
generated buffer-handling logic is localized to that function. This
includes how it handles buffers generated for ReplacedFunctionBody.
- getOriginalLocation() is used in a couple of other places that only
care about macros expanded from the same buffer (so other generated
buffers not not relevant). This "macro-chasing" logic is simplified
and moved from ModuleDecl::getOriginalRange() to a free-standing
function, getMacroUnexpandedRange() (there is no reason for it to be
a method of ModuleDecl).
- GeneratedSourceInfo now carries an extra ClangNode field, which is
populated by getClangSwiftAttrSourceFile() when constructing
a generated buffer for an 'AttributeFromClang'. This could probably
be union'ed with one or more of the other fields in the future.
rdar://151020332
Ideally we'd be able to use the llvm interleave2 and deinterleave2
intrinsics instead of adding these, but deinterleave currently isn't
available from Swift, and even if you hack that in, the codegen from
LLVM is worse than what shufflevector produces for both x86 and arm. So
in the medium-term we'll use these builtins, and hope to remove them in
favor of [de]interleave2 at some future point.
When building against the static standard library, we should define
`SWIFT_STATIC_STDLIB` to indicate to the shims that the declarations
should be giving hidden visibility and default DLL storage. This is
required to ensure that these symbols are known to be `dso_local` when
compiling to avoid an unnecessary look up through the PLT/GOT or the
indirection through the synthesized `__imp_` symbol and the IAT. This
corrects a number of incorrect code generation cases on Windows with the
static standard library.
Create a path that swift-frontend can execute an uncached job from
modules built with CAS based explicit module build. The new flag
-import-module-from-cas will allow an uncached build to load module
from CAS, and combined with source file from real file system to build
the current module. This allows quick iterations that bypasses CAS,
without full dependency scanning every time in between.
rdar://152441866
Textual interfaces for 'Darwin' built with recent compilers specify that it is built witout C++ interop enabled. However, to ensure compatibility with versions of the 'Darwin' module built with older compilers, we hard-code this fact. This is required to break the module cycle that occurs when building the 'Darwin' module with C++ interop enabled, where the underlying 'Darwin' clang module depends on C++ standard library for which the compiler brings in the 'CxxStdlib' Swift overlay, which depends on 'Darwin'.
The migration to `MemberImportVisibility` can be performed mechanically by
adding missing import declarations, so offer automatic migration for the
feature.
Resolves rdar://151931597.
