When a Swift module built with debug info imports a library without
debug info from a textual interface, the textual interface is
necessary to reconstruct types defined in the library's interface. By
recording the Swift interface files in DWARF dsymutil can collect them
and LLDB can find them.
rdar://problem/49751363
A module compiled with `-enable-private-imports` allows other modules to
import private declarations if the importing source file uses an
``@_private(from: "SourceFile.swift") import statement.
rdar://29318654
This can't arise from a clean build, but it can happen if you have
products lingering in a search path and then either rebuild one of
the modules in the cycle, or change the search paths.
The way this is implemented is for each module to track whether its
imports have all been resolved. If, when loading a module, one of its
dependencies hasn't resolved all of its imports yet, then we know
there's a cycle.
This doesn't produce the best diagnostics, but it's hard to get into
this state in the first place, so that's probably okay.
https://bugs.swift.org/browse/SR-7483
Deserializing a witness record in a conformance may fail if either of the requirement or witness changed name or type, most likely due to SDK modernization changes across Swift versions. When this happens, leave an opaque placeholder in the conformance to indicate that the witness exists but we don't get to see it. For expedience, right now this just witnesses the requirement to itself, so that code in the type checker or elsewhere that tries to ad-hoc devirtualize references to the requirement just gets the requirement back. Arguably, we shouldn't include the witness at all in imported conformances, since they should be an implementation detail, but that's a bigger, riskier change. This patch as is should be enough to address rdar://problem/31185053.
That is, a Swift 3 target imported into a Swift 4 context or vice
versa. This requires serializing the compatibility mode explicitly,
instead of including it in the textual version string that's only
for debugging.
...with a better message than the generic "older version of the
compiler" one, when we know it's actually a different version of
Swift proper.
This still uses the same internal module version numbers to check
if the module is compatible; the presentation of language versions
is a diagnostic thing only.
Speaking of module version numbers, this deliberately does NOT
increment VERSION_MINOR; it's implemented in a backwards-compatible
way.
This will only work going forwards, of course; all existing modules
don't have a short version string, and I don't feel comfortable
assuming all older modules we might encounter are "Swift 2.2".
rdar://problem/25680392
We want to distinguish the special case of a library built with
-sil-serialize-all, from a SIL function that is [fragile] because
of an explicitly @_transparent or @inline(__always).
For now, NFC.
Since resilience is a property of the module being compiled,
not decls being accessed, we need to record which types are
resilient as part of the module.
Previously we would only ever look at the @_fixed_layout
attribute on a type. If the flag was not specified, Sema
would slap this attribute on every type that gets validated.
This is wasteful for non-resilient builds, because there
all types get the attribute. It was also apparently wrong,
and I don't fully understand when Sema decides to validate
which decls.
It is much cleaner conceptually to just serialize this flag
with the module, and check for its presence if the
attribute was not found on a type.
Also into a separate file.
Before (swift/Serialization/SerializedModuleLoader.h):
ModuleStatus
SerializedModuleLoader::ValidationInfo
SerializedModuleLoader::ExtendedValidationInfo
SerializedModuleLoader::isSerializedAST
SerializedModuleLoader::validateSerializedAST
After (swift/Serialization/Validation.h):
serialization::Status
serialization::ValidationInfo
serialization::ExtendedValidationInfo
serialization::isSerializedAST
serialization::validateSerializedAST
No functionality change, just a lot of renaming and a bit of reorganizing.
Swift SVN r25226
