This patch removes the ability of a dependency scanning worker to share a `FileManager` instance between individual scans. It's not sound and doesn't provide performance benefits (due to the underlying caching VFS).
Reviewed By: benlangmuir
Differential Revision: https://reviews.llvm.org/D134976
the dependency scanner on a single worker thread
This behavior can be controlled using the new `-reuse-filemanager` clang-scan-deps
option. By default the file manager is reused.
The added test/ClangScanDeps/symlink.cpp is able to pass with
the reused filemanager after the related FileEntryRef changes
landed earlier. The test test/ClangScanDeps/subframework_header_dir_symlink.m
still fails when the file manager is reused (I run the FileCheck with not to
make it PASS). I will address this in a follow-up patch that improves
the DirectoryEntry name modelling in the FileManager.
llvm-svn: 370420
Jan Svoboda