[clang] Reland "[clang][modules] Print library module manifest path." (PR #82160)

[Kazushi Marukawa via cfe-commits]

kaz7 wrote:

The point is to build libraries and test clang.  The `TC.getFilePaths` is constructed from following items in `ToolChain::ToolChain`

1. `BUILD/bin/../lib/x86_64-unknown-linux-gnu`
2. `%t/Inputs/usr/lib/x86_64-linux-gnu`
3. `%t/Inputs/usr/lib`

Yes.  It contains 1st item at run time if you build not only clang but also libraries.  And `GetStdModuleManifestPath` find `BUILD/bin/../lib/x86_64-unknown-linux-gnu/libc++.so` at first.  However, `modules.json` is not in that directory.  It is in `%t/Inputs/usr/lib/x86_64-linux-gnu/modules.json`.

Hope this helps you.


https://github.com/llvm/llvm-project/pull/82160