Separate swift-syntax libs for the compiler and for the library plugins.
Compiler communicates with library plugins using serialized messages
just like executable plugins.
* `lib/swift/host/compiler/lib_Compiler*.dylib`(`lib/CompilerSwiftSyntax`):
swift-syntax libraries for compiler. Library evolution is disabled.
* Compiler (`ASTGen` and `swiftIDEUtilsBridging`) only depends on
`lib/swift/host/compiler` libraries.
* `SwiftInProcPluginServer`: In-process plugin server shared library.
This has one `swift_inproc_plugins_handle_message` entry point that
receives a message and return the response.
* In the compiler
* Add `-in-process-plugin-server-path` front-end option, which specifies
the `SwiftInProcPluginServer` shared library path.
* Remove `LoadedLibraryPlugin`, because all library plugins are managed
by `SwiftInProcPluginServer`
* Introduce abstract `CompilerPlugin` class that has 2 subclasses:
* `LoadedExecutablePlugin` existing class that represents an
executable plugin
* `InProcessPlugins` wraps `dlopen`ed `SwiftInProcPluginServer`
* Unified the code path in `TypeCheckMacros.cpp` and `ASTGen`, the
difference between executable plugins and library plugins are now
abstracted by `CompilerPlugin`
`-disable-sandbox` to disable sandboxing when invoking subprocess from
from the frontend. Since `sandbox(7)` in macOS doesn't support nested
sandbox, complation used to fail when the parent build process is sandboxed.
Instead of emitting an warning to the diagnostic engine, return the
plugin loading error as the result of the request. So that the user
can decide to emit it as a warning or an error.
Iterating all options and potential file system access is not great for
every plugin lookup request. Instead, lazily create a single lookup table
keyed by module name.
'load-plugin-library', 'load-plugin-executable', '-plugin-path' and
'-external-plugin-path' should be searched in the order they are
specified in the arguments.
Previously, for example '-plugin-path' used to precede
'-external-plugin-path' regardless of the position in the arguments.
* Factor out ASTContext plugin loading to newly introduced 'PluginLoader'
* Insert 'DependencyTracker' to 'PluginLoader'
* Add dependencies right before loading the plugins
rdar://104938481
