PE/COFF does not provide weak linking semantics. Ensure that we
diagnose use of `_weakLinked` on those targets rather than consuming it
and attempting to generate IR for that.
This is a new feature of Swift 5 mode, so it deserves at least a
little bit of explanation right in the diagnostic. If you have an
otherwise-fully-covered switch but can't assume the enum is frozen,
you'll now get this message:
switch covers known cases, but 'MusicGenre' may have additional
unknown values
Furthermore, if the enum comes from a system header, it looks like
this:
switch covers known cases, but 'NSMusicGenre' may have additional
unknown values, possibly added in future versions
...to further suggest the idea that even though your switch is covered
/now/, it might not handle everything in the /future/. This extra bit
is limited to system headers to avoid showing up on C enums defined in
your own project, for which it sounds silly. (The main message is
still valid though, since you can cram whatever you want into a C
enum, and people use this pattern to implement "private cases".)
rdar://problem/39367045
Sometimes constraint solver fails without producing any diagnostics,
it could happen during different phases e.g. pre-check, constraint
generation, or even while attempting to apply solution. Such behavior
leads to crashes down the line in AST Verifier or SILGen which are
hard to diagnose.
Let's guard against that by tracking if solver produced any diagnostics
upon its failure and if no errors were or are scheduled to be produced,
let's produce a fallback fatal error pointing at affected expression.
Resolves: rdar://problem/38885760
This fixes the Windows platform, where the aligned allocation path is
not malloc-compatible. It won't have any observable difference on
Darwin or Linux, aside from manually allocated memory on Linux now
being consistently 16-byte aligned (heap objects will still be 8-byte
aligned on Linux).
It is unfortunate that we can't guarantee Swift-allocated memory via
Unsafe*Pointer is malloc compatible on Windows. It would have been
nice for that to be a cross platform guarantee since it's normal to
allocate in C and deallocate in Swift or vice-versa. Now we have to
tell developers to always use _aligned_malloc/_aligned_free when
transitioning between Swift/C if they expect their code to work on
Windows.
Even though this fix isn't required today on Darwin/Linux, it makes
good sense to guarantee that the allocation/deallocation paths are
consistent.
This is done by specifying a constant that stdlib can use to round up
alignment, _swift_MinAllocationAlignment. The runtime asserts that
this constant is greater than MALLOC_ALIGN_MASK for all platforms.
This way, manually allocated buffers will always use the aligned
allocation path. If users specify an alignment less than m
round up so users don't need
to pass the same alignment to deallocate the buffer). This constant
does not need to be ABI.
Alternatives are:
1. Require users of Unsafe*Pointer to specify the same alignment
during deallocation. This is obviously madness.
2. Introduce new runtime entry points:
swift_alignedAlloc/swift_alignedDealloc, introduce corresponding
new builtins, and have Unsafe*Pointer always call those. This would
make the runtime API a little more obvious but would introduce
complexity in other areas of the compiler and it doesn't have any
other significant benefit. Less than 16-byte alignment of manually
allocated buffers on Linux is a non-goal.
Otherwise we generate a call to String(reflecting:), which correctly handles many things we may not be able to (like private types), and which matches the default implementation of Error._domain.
We weren't doing much validation when dynamically replacing storage
declarations, and has an assert() that should be an error. Clean up this
area a bit, dealing with simple ambiguities (i.e., there are two
properties or subscripts with different type signatures; pick the
matching one) and reporting an error when there is a true ambiguity.
Fixes rdar://problem/46737657.
Removes the _getBuiltinLogicValue intrinsic in favor of an open-coded
struct_extract in SIL. This removes Sema's last non-literal use of builtin
integer types and unblocks a bunch of cleanup.
This patch would be NFC, but it improves line information for conditional expression codegen.
Sema would directly check for the presence of the @objcMembers attribute,
and inherit it from the immediate superclass in validateDecl().
We don't want validateDecl() to have side effects like this and this was
already a problem, because it would not inherit the attribute transitively
in some cases.
Instead, add a ClassDecl::hasObjCMembers() method that walks over all
ancestors and caches the result.
<rdar://problem/46420252>
Context archetypes and opened existential archetypes differ in a number of details, and this simplifies the overlapping storage of the kind-specific fields. This should be NFC; for now, this doesn't change the interface of ArchetypeType, but should allow some refinements of how the special handling of certain archetypes are handled.
GenericParamList::OuterParameters would mirror the nesting structure
of generic DeclContexts. This resulted in redundant code and caused
unnecessary complications for extensions and protocols, whose
GenericParamLists are constructed after parse time.
Instead, lets only use OuterParameters to link together the multiple
parameter lists of a single extension, or parameter lists in SIL
functions.
Previously the cast optimizer bailed out on any conformance with
requirements.
We can now constant-propagate this:
```
protocol P {}
struct S<E> {
var e: E
}
extension S : P where E == Int {}
func specializeMe<T>(_ t: T) {
if let p = t as? P {
// do fast things.
}
}
specializeMe(S(e: 0))
```
This turns out to be as simple as calling the TypeChecker.
<rdar://problem/46375150> Inlining does not seem to handle
specialization properly for Data.
This enabled two SIL transformations required to optimize
the code above:
(1) The witness method call can be devirtualized.
(2) The allows expensive dynamic runtime checks such as:
unconditional_checked_cast_addr Array<UInt8> in %array : $*Array<UInt8> to ContiguousBytes in %protocol : $*ContiguousBytes
Will be converted into:
%value = init_existential_addr %existential : $*ContiguousBytes, $Array<UInt8>
store %array to %value : $*Array<UInt8>
For now Sema still calls it manually, but soon we could make
getGenericParams() lazy, calling this automatically, since
there's really no reason to create the generic parameters
upfront when binding the extension.
Instead of creating multiple CodeBlockItemList nodes, that need to get merged and discarded later on, do this:
* Ensure for libSyntax parsing that we parse the whole file
* Create top-level CodeBlockItem nodes that we just directly wrap with a single CodeBlockItemList node at the end
The importance of this change will become more obvious later on when we'll decouple syntax parsing from the formation of libSyntax tree nodes.
This was a nice feature when people said "-swift-version 3.1"...
up until we got "-swift-version 4.2" as an actual valid version.
Just drop the special case.
https://bugs.swift.org/browse/SR-8850
<rdar://problem/46548531> Extend @available to support PackageDescription
This introduces a new private availability kind "_PackageDescription" to
allow availability testing by an arbitary version that can be passed
using a new command-line flag "-swiftpm-manifest-version". The semantics
are exactly same as Swift version specific availability. In longer term,
it maybe possible to remove this enhancement once there is
a language-level availability support for 3rd party libraries.
Motivation:
Swift packages are configured using a Package.swift manifest file. The
manifest file uses a library called PackageDescription, which contains
various settings that can be configured for a package. The new additions
in the PackageDescription APIs are gated behind a "tools version" that
every manifest must declare. This means, packages don't automatically
get access to the new APIs. They need to update their declared tools
version in order to use the new API. This is basically similar to the
minimum deployment target version we have for our OSes.
This gating is important for allowing packages to maintain backwards
compatibility. SwiftPM currently checks for API usages at runtime in
order to implement this gating. This works reasonably well but can lead
to a poor experience with features like code-completion and module
interface generation in IDEs and editors (that use sourcekit-lsp) as
SwiftPM has no control over these features.
Validating a declaration can trigger conformance checking. If the conformance checker
comes across the same declaration as a candidate witness, it would fail to emit a
diagnostic. As a result we would then go onto SILGen, which would crash while emitting
a witness table with a missing entry.
Fixes <rdar://problem/45151902>.
