Put AvailabilityRange into its own header with very few dependencies so that it
can be included freely in other headers that need to use it as a complete type.
NFC.
A `@backDeployed` function printed in a `.swiftinterface` must have a function
body so that SILGen can emit a fallback copy to call when the back deployed
function is unavailable. Previously, the compiler would crash in SILGen when
compiling an interface containing a back deployed function without a body.
Resolves rdar://141593108.
This attribute makes it so that a parameter of the annotated type, as well as
any type structurally containing that type as a field, becomes passed as
if `@_addressable` if the return value of the function has a dependency on
the parameter. This allows nonescapable values to take interior pointers into
such types.
Right now it is basically a version of nonisolated beyond a few simple cases
like constructors/destructors where we are pretty sure we want to not support
this.
This is part of my bringup strategy for changing nonisolated/unspecified to be
caller isolation inheriting.
I need this today to add the implicit isolated parameter... but I can imagine us
adding more implicit parameters in the future, so it makes sense to formalize it
so it is easier to do in the future.
Add a -nostdlibimport (analagous to clang's -nostdlibinc) to remove the SDK paths from the import search paths, but leave the toolchain paths.
rdar://139322299
Extend the module trace format with a field indicating whether a given
module, or any module it depends on, was compiled with strict memory
safety enabled. This separate output from the compiler can be used as
part of an audit to determine what parts of Swift programs are built
with strict memory safety checking enabled.
As we do when referencing other kinds of declarations, if a
typealias isn't `@unsafe`, but it involves unsafe types,
diagnose the non-safety at the point of reference.
Fixes https://github.com/swiftlang/swift/issues/78220
When Swift passes search paths to clang, it does so directly into the HeaderSearch. That means that those paths get ordered inconsistently compared to the equivalent clang flag, and causes inconsistencies when building clang modules with clang and with Swift. Instead of touching the HeaderSearch directly, pass Swift search paths as driver flags, just do them after the -Xcc ones.
Swift doesn't have a way to pass a search path to clang as -isystem, only as -I which usually isn't the right flag. Add an -Isystem Swift flag so that those paths can be passed to clang as -isystem.
rdar://93951328
The `@unchecked` conformance is effectively the same as
`@safe(unchecked)`, in that it asserts memory safety in a place where
it cannot be automatically checked. But once that has been asserted,
there is no reason to diagnose anywhere else.
While here, drop the "unsafe declaration here" note, which isn't
adding value but did add noise.
Thanks, Alex!
Protocol conformances have a handful attributes that can apply to them
directly, including @unchecked (for Sendable), @preconcurrency, and
@retroactive. Generalize this into an option set that we carry around,
so it's a bit easier to add them, as well as reworking the
serialization logic to deal with an arbitrary number of such options.
Use this generality to add support for @unsafe conformances, which are
needed when unsafe witnesses are used to conform to safe requirements.
Implement general support for @unsafe conformances, including
producing a single diagnostic per missing @unsafe that provides a
Fix-It and collects together all of the unsafe witnesses as notes.
@preconcurrency imports disable Sendable checking, which can lead to
data races that undermine memory safety. Diagnose such imports, and
require `@safe(unchecked)` to suppress the diagnostic.
Under strict concurrency and memory safety, uses of `@unchecked
Sendable` conformances are considered unsafe. Diagnose the use sites,
not the declaration site.
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.
A `@backDeployed` function printed in a `.swiftinterface` must have a function
body so that SILGen can emit a fallback copy to call when the back deployed
function is unavailable. Previously, the compiler would crash in SILGen when
compiling an interface containing a back deployed function without a body.
Resolves rdar://141593108.
A nonisolated(unsafe) declaration clearly indicates that the
declaration itself is unsafe, so it doesn't need to be diagnosted.
Instead, diagnose any reference to such a declaration that occurs
when strict concurrency is enabled. Make this a collatable unsafe use.
Instead of producing a warning for each use of an unsafe entity,
collect all of the uses of unsafe constructs within a given function
and batch them together in a single diagnostic at the function level
that tells you what you can do (add `@unsafe` or `@safe(unchecked)`,
depending on whether all unsafe uses were in the definition), plus
notes identifying every unsafe use within that declaration. The new
diagnostic renderer nicely collects together in a single snippet, so
it's easier to reason about.
Here's an example from the embedded runtime that previously would have
been 6 separate warnings, each with 1-2 notes:
```
swift/stdlib/public/core/EmbeddedRuntime.swift:397:13: warning: global function 'swift_retainCount' involves unsafe code; use '@safe(unchecked)' to assert that the code is memory-safe
395 |
396 | @_cdecl("swift_retainCount")
397 | public func swift_retainCount(object: Builtin.RawPointer) -> Int {
| `- warning: global function 'swift_retainCount' involves unsafe code; use '@safe(unchecked)' to assert that the code is memory-safe
398 | if !isValidPointerForNativeRetain(object: object) { return 0 }
399 | let o = UnsafeMutablePointer<HeapObject>(object)
| | `- note: call to unsafe initializer 'init(_:)'
| `- note: reference to unsafe generic struct 'UnsafeMutablePointer'
400 | let refcount = refcountPointer(for: o)
| | `- note: reference to let 'o' involves unsafe type 'UnsafeMutablePointer<HeapObject>'
| `- note: call to global function 'refcountPointer(for:)' involves unsafe type 'UnsafeMutablePointer<Int>'
401 | return loadAcquire(refcount) & HeapObject.refcountMask
| | `- note: reference to let 'refcount' involves unsafe type 'UnsafeMutablePointer<Int>'
| `- note: call to global function 'loadAcquire' involves unsafe type 'UnsafeMutablePointer<Int>'
402 | }
403 |
```
Note that we have lost a little bit of information, because we no
longer produce "unsafe declaration was here" notes pointing back at
things like `UnsafeMutablePointer` or `recountPointer(for:)`. However,
strict memory safety tends to be noisy to turn on, so it's worth
losing a little bit of easily-recovered information to gain some
brevity.
