The code, previously, only properly handled such dependencies being a distinct category for Swift source and Swift textual dependency infos. Swift binary module dependencies must handle this similarly and this change adds the missing support for them. Recent refactor of the scanner also means that now Swift binary dependencies with Swift overlay dependencies may crash the scanner, and this change resolves this as well.
Resolves rdar://117088840
There is a special case that already exists in 'ClangImporter' for implicit module loading:
Import of a "submodule" named "Foo.Private" is treated as a top-level module named "Foo_Private".
Clang has special support for this.
Resolves rdar://108287140
When building a set of command-line options required to build a Clang module, also add `NonPathCommandLine` from Clang's `ModuleDeps`. These flags are mandatory in order to build modules discovered by the scanner.
Resolves rdar://70212660
This ensures that when the dependency scanner is invoked with additional clang (`-Xcc`) options, the Clang scanner is correctly configured using these options.
To help solving rdar://67079780, this change allows swift-driver to configure scanner using additional
arguments passed down via the batch input JSON file for each module under scanning.
Additional flags in interface files may change parsing behavior like #if
statements. We should use a fresh ASTContext with these additional
flags when parsing interface files to collect imports.
rdar://62612027
When there is a bridging header associated with the module, scan and record
its dependencies. Note them in a separate structure to capture the specific
dependencies of the bridging header.
Implement a new "fast" dependency scanning option,
`-scan-dependencies`, in the Swift frontend that determines all
of the source file and module dependencies for a given set of
Swift sources. It covers four forms of modules:
1) Swift (serialized) module files, by reading the module header
2) Swift interface files, by parsing the source code to find imports
3) Swift source modules, by parsing the source code to find imports
4) Clang modules, using Clang's fast dependency scanning tool
A single `-scan-dependencies` operation maps out the full
dependency graph for the given Swift source files, including all
of the Swift and Clang modules that may need to be built, such
that all of the work can be scheduled up front by the Swift
driver or any other build system that understands this
option. The dependency graph is emitted as JSON, which can be
consumed by these other tools.
