When building on Alpine with Musl `__has_feature(is_trivially_constructible)` does not work, even though `__is_trivially_constructible` is defined and `__has_trivial_constructor` is deprecated. Same for `__is_trivially_destructible` and `__has_trivial_destructor` respectively.
For some reason LLVM doesn't provide this. I have written a few versions of this
in the Swift codebase. Makes sense to factor it out before I make another one.
When emitting a diagnostic that references a declaration that does not
itself have a source location (e.g., because it was synthesized or
deserialized), the diagnostics engine pretty-prints the declaration
into a buffer so it can provide caret diagnostics pointing to that
declaration.
Start marking those buffers as "generated source buffers", so that we
emit their contents into serialized diagnostics files. This will allow
tools that make use of serialized diagnostics to also show caret
information.
When a declaration has a structural opaque return type like:
func foo() -> Bar<some P>
then to mangle that return type `Bar<some P>`, we have to mangle the `some P`
part by referencing its defining declaration `foo()`, which in turn includes
its return type `Bar<some P>` again (this time using a special mangling for
`some P` that prevents infinite recursion). Since we mangle `Bar<some P>`
once as part of mangling the declaration, and we register substitutions for
bound generic types when they're complete, we end up registering the
substitution for `Bar<some P>` twice, once as the return type of the
declaration name, and again as the actual type. This would be fine, except
that the mangler doesn't check for key collisions, and it picks
substitution indexes based on the number of entries in its hash map, so
the duplicated substitution ends up corrupting the substitution sequence,
causing the mangler to produce an invalid mangled name.
Fixing that exposes us to another problem in the remangler: the AST
mangler keys substitutions by type identity, but the remangler
uses the value of the demangled nodes to recognize substitutions.
The mangling for `Bar<current declaration's opaque return type>` can
appear multiple times in a demangled tree, but referring to different
declarations' opaque return types, and the remangler would reconstruct
an incorrect mangled name when this happens. To avoid this, change the
way the demangler represents `OpaqueReturnType` nodes so that they
contain a backreference to the declaration they represent, so that
substitutions involving different declarations' opaque return types
don't get confused.
Each macro expansion buffer was getting parsed twice: once by
ParseSourceFileRequest (which is used by unqualified name lookup) and
once to parse the expression when type-checking the expanded macro.
This meant that the same code had two ASTs. Hilarity ensures.
Stop directly invoking the parser on macro-expanded code. Instead, go
through ParseSourceFileRequest *as is always the right way*, and dig
out the expression we want.
Introduce the experimental feature `ParserDiagnostics`, which emits
diagnostics from the new Swift parser *first* for a source file. If
that produces any errors, we suppress any diagnostics emitted from the
C++ parser.
Establish the relationship for generated sources, whether for macro
expansions or (via a small stretch) replacing function bodies with
other bodies, in the source manager itself. This makes the information
available for diagnostic rendering, and unifies a little bit of the
representation, although it isn't used for much yet.
Introduce a new behavior when printing references to modules with an
`export_as` definition. Use the `export_as` name in the public swiftinterface
and the real module name in the private swiftinterface.
This has some limits but should still be an improvement over the current
behavior. First, the we use the `export_as` names only for references to clang
decls, not Swift decls with an underlying module defining an `export_as`.
Second, we always print the `export_as` name in the public swiftinterface,
even in the original swiftinterface file when the `export_as` target is likely
not know, so that generated swiftinterface is still broken.
This behavior is enabled by the flags `-enable-experimental-feature ModuleInterfaceExportAs`
or the `SWIFT_DEBUG_USE_EXPORTED_MODULE_NAME_IN_PUBLIC_ONLY` env var. We may
consider turning it on by default in the future.
rdar://98532918
Introduces a concept of a dependency scanning action context hash, which is used to select an instance of a global dependency scanning cache which gets re-used across dependency scanning actions.
`getValue` -> `value`
`getValueOr` -> `value_or`
`hasValue` -> `has_value`
`map` -> `transform`
The old API will be deprecated in the rebranch.
To avoid merge conflicts, use the new API already in the main branch.
rdar://102362022
