[PATCH] D41005: Reuse preamble even if an unsaved file does not exist

[Ilya Biryukov via Phabricator via cfe-commits]

ilya-biryukov added a comment.

In https://reviews.llvm.org/D41005#949550, @cameron314 wrote:

> It's been a while since I was in this code, but I seem to recall the file needed to exist on disk in order to uniquely identify it (via inode). Does this break the up-to-date check?


When the file is missing from the disk, but was remapped, preamble can not be reused. (Because we're always looking at uniqueids).
If the remapped file did not exist on disk originally when building the preamble, we should allow the preamble to be reused if it's still remapped, but not created on disk.


Repository:
  rC Clang

https://reviews.llvm.org/D41005