swift

acb4e847 - [Dependency Scanning] Add functionality to validate contents of a loaded scanner cache state

[Dependency Scanning] Add functionality to validate contents of a loaded scanner cache state Checking each module dependency info if it is up-to-date with respect to when the cache contents were serialized in a prior scan. - Add a timestamp field to the serialization format for the dependency scanner cache - Add a flag "-validate-prior-dependency-scan-cache" which, when combined with "-load-dependency-scan-cache" will have the scanner prune dependencies from the deserialized cache which have inputs that are newer than the prior scan itself With the above in-place, the scan otherwise proceeds as-is, getting cache hits for entries still valid since the prior scan.