When a translation unit uses a PCH and imports the same modules as the PCH, we'd prefer to resolve to those modules instead of inventing new modules and reporting them as modular dependencies. Since the PCH modules have already been built nudge the compiler to reuse them when deciding whether to build a new module and don't report them as regular modular dependencies.
Depends on D103524 & D103802.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D103526
When a project uses PCH with explicit modules, the build will look like this:
1. scan PCH dependencies
2. explicitly build PCH
3. scan TU dependencies
4. explicitly build TU
Step 2 produces an object file for the PCH, which the dependency scanner needs to read in step 3. This patch adds support for this.
The `clang-scan-deps` invocation in the attached test would fail without this change.
Depends on D103516.
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D103519
Jan Svoboda