Our mangling did not encode if an Objective-C block was escaping or
not. This is not a huge problem in practice, but for debug info we
want type reconstruction to round-trip exactly. There was a previous
workaround to paper over this specific problem.
Remove the workaround, and add a new 'XL' mangling for escaping
blocks. Since we don't actually want to break ABI compatibility,
only use the new mangling in DWARF debug info.
Error structs synthesized by ClangImporter can be renamed using SWIFT_NAME() to syntactically appear anywhere in the type hierarchy with any name, but they should always be mangled as `__C_Synthesized.related decl ‘e’ of <Objective-C enum name>`. Unforunately, when SWIFT_NAME() was used to nest the error struct inside another type, an ASTMangler bug would cause it to be mangled as `<parent type>.related decl ‘e’ of <Objective-C enum name>`, and an ASTDemangler bug would also require a valid parent type. This created a mismatch between the compiler’s and runtime’s manglings which caused crashes when you tried to match the imported error struct in a `catch`.
This PR corrects the compiler bugs so that it generates the mangling the runtime expects. This is theoretically ABI-breaking, but as far as I can determine nobody has shipped the incorrectly mangled names, presumably because they crash when you try to use them.
Fixes <rdar://problem/48040880>.
Fixes a crash in IRGen
TODO: also fix the demangler/remangler part of this mangling change.
Currently it's not a problem because we never demangle such a symbol (it's even not round-trip checked in Mangler::verify).
rdar://problem/50405691
Fix a trio of issues involving mangling for opaque result types:
* Symbolic references to opaque type descriptors are not substitutions
* Mangle protocol extension contexts correctly
* Mangle generic arguments for opaque result types of generic functions
The (de-)serialization of generic parameter lists for opaque type
declarations is important for the last bullet, to ensure that the
mangling of generic arguments of opaque result types works across
module boundaries.
Fixes the rest of rdar://problem/50038754.
When printing a swiftinterface, represent opaque result types using an attribute that refers to
the mangled name of the defining decl for the opaque type. To turn this back into a reference
to the right decl's implicit OpaqueTypeDecl, use type reconstruction. Since type reconstruction
doesn't normally concern itself with non-type decls, set up a lookup table in SourceFiles and
ModuleFiles to let us handle the mapping from mangled name to opaque type decl in type
reconstruction.
(Since we're invoking type reconstruction during type checking, when the module hasn't yet been
fully validated, we need to plumb a LazyResolver into the ASTBuilder in an unsightly way. Maybe
there's a better way to do this... Longer term, at least, this surface design gives space for
doing things more the right way--a more request-ified decl validator ought to be able to naturally
lazily service this request without the LazyResolver reference, and if type reconstruction in
the future learns how to reconstruct non-type decls, then the lookup tables can go away.)
Escapingness is a property of the type of a value, not a property of a function
parameter. Having it as a separate parameter flag just meant one more piece of
state that could get out of sync and cause weird problems.
Instead, always look at the noescape bit in a function type as the canonical
source of truth.
This does mean that '@escaping' is now printed in a few diagnostics where it was
not printed before; we can investigate these as separate issues, but it is
correct to print it there because the function types in question are, in fact,
escaping.
Fixes <https://bugs.swift.org/browse/SR-10256>, <rdar://problem/49522774>.
This was partially implemented but the check looked at the lowered
types and not the AST types, and DynamicSelfType is erased at the
top level of a lowered type.
Also use the new mangling for reabstraction thunks with self, to
ensure we don't emit the same symbol with two different lowered
types.
Fixes <https://bugs.swift.org/browse/SR-10309>, <rdar://problem/49703441>.
For now, this means USRs of ParamDecls. Soon, default argument generators
for subscripts will need this too.
Fixes <https://bugs.swift.org/browse/SR-8660>, <rdar://problem/44435221>.
When emitting metadata for a Swift-defined @objc protocol that has
provided a specific Objective-C name (e.g., via @objc(renamed)),
mangle such protocols using their Objective-C names so they can be
found at runtime.
Only do this for metadata, because doing it anywhere else would cause
an ABI break. Fixes rdar://problem/47877748.
Add an IRGen flag to disable this verification, since it doesn't work from within
lldb itself for some reason, and I don't want to investigate it right now.
Swift.UnicodeScalar is a typealias now, and for the TypeDecoder
to work correctly we need to mangle it as a typealias and not as
a struct.
However, we still want to demangle old names that used the
substitution, so don't remove it, instead just skip checking for
a substitution when mangling a typealias.
This does not change the ABI; typealiases are only mangled as
part of debug info.
New(er) grammar:
// same module as conforming type, or non-unique
protocol-conformance-ref ::= protocol 'HP'
// same module as protocol
protocol-conformance-ref ::= protocol 'Hp'
// retroactive
protocol-conformance-ref ::= protocol module
We don't make use of this distinction anywhere yet, but we could in
the future.
Previously, the mangler searched for retroactive conformances in /any/
of a generic type's substitutions, but really we only care about the
ones that affect the generic type's conformance, i.e. those that
affect generic parameters. Refining this results in shorter mangled
names involving instantiations of generic types.
Follow-up work for rdar://problem/46735592
Fix to 510b64fcd5. The mangling operator "HP" has to distinguish
between "protocol" and "protocol module", not between the presence
or absence of protocol-conformance-ref. New grammar:
protocol-conformance-ref ::= protocol
protocol-conformance-ref ::= protocol module 'HP'
rdar://problem/46735592, again
Due to some unfortunate refactoring, protocol-conformance-ref is a
nonterminal in the mangling grammar that doesn't have its own
operator:
```
protocol-conformance-ref ::= protocol module?
```
Both "module" and "protocol" can be an "identifier", which introduces
a mangling collision. Address the mangling collision by using the
operator "HP".
Fixes rdar://problem/46735592.
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.
While declaration mangling now does the right thing for parameter lists,
the function type mangling unfortunately still models the parameter list
as a single tuple node.
Change the runtime's behavior to match the AST mangler, which wraps
a single tuple-typed parameter in a tuple node, so that we can produce
different mangling trees for function types taking multiple arguments
versus a single tuple argument.
Instead of trying to mangle a tuple type.
This change avoids mangling tuple element names in case a field type is a tuple with named elements.
Fixes a "can't demangle" crash in the closure specializer.
This mangling is only used for specializations, so no ABI effect.
rdar://problem/46380088
When debugging Objective-C or C++ code on Darwin, the debug info
collected by dsymutil in the .dSYM bundle is entirely
self-contained. It is possible to debug a program, set breakpoints and
print variables even without having the complete original source code
or a matching SDK available. With Swift, this is currently not the
case. Even though .dSYM bundles contain the binary .swiftmodule for
all Swift modules, any Clang modules that the Swift modules depend on,
still need to be imported from source to even get basic LLDB
functionality to work. If ClangImporter fails to import a Clang
module, effectively the entire Swift module depending on it gets
poisoned.
This patch is addressing this issue by introducing a ModuleLoader that
can ask queries about Clang Decls to LLDB, since LLDB knows how to
reconstruct Clang decls from DWARF and clang -gmodules producxes full
debug info for Clang modules that is embedded into the .dSYM budle.
This initial version does not contain any advanced functionality at
all, it merely produces an empty ModuleDecl. Intertestingly, even this
is a considerable improvement over the status quo. LLDB can now print
Swift-only variables in modules with failing Clang depenecies, and
becuase of fallback mechanisms that were implemented earlier, it can
even display the contents of pure Objective-C objects that are
imported into Swift. C structs obviously don't work yet.
rdar://problem/36032653
LibraryEvolution.rst stipulates that adding or removing 'weak',
'unowned' and 'unowned(unsafe)' is a resilient change if the type
is resilient. This means we should not mangle these attributes as
part of the accessor declaration.
The mangling AST cannot represent this, and we were incorrectly
pulling generic arguments from the type alias type. Instead let's
just desugar the parent type when mangling a nominal type.
Fixes <rdar://problem/45900947>.
