This patch changes type of the `File` parameter in `PPCallbacks::InclusionDirective()` from `const FileEntry *` to `Optional<FileEntryRef>`.
With the API change in place, this patch then removes some uses of the deprecated `FileEntry::getName()` (e.g. in `DependencyGraph.cpp` and `ModuleDependencyCollector.cpp`).
Reviewed By: dexonsmith, bnbarham
Differential Revision: https://reviews.llvm.org/D123574
The `{HeaderSearch,Preprocessor}::LookupFile()` functions take an out-parameter `const DirectoryLookup *&`. Most callers end up creating a `const DirectoryLookup *` variable that's otherwise unused.
This patch changes the out-parameter from reference to a pointer, making it possible to simply pass `nullptr` to the function without the ceremony.
Reviewed By: ahoppen
Differential Revision: https://reviews.llvm.org/D117312
Add methods for emitting diagnostics with no location as well as a special diagnostic for configuration errors.
These show up in the errors as [clang-tidy-config].
The reason to use a custom name rather than the check name is to distinguish the error isn't the same category as the check that reported it.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D91885
Jan Svoboda