[PCH] Be conservative and check all the files the PCH references to see if
a file was modified since the time the PCH was created.

The parser is not fit to deal with stale PCHs, too many invariants do not hold up. rdar://9530587.

llvm-svn: 132389
3 files changed
tree: 6a8dd52a76665328ae2da07936497477469f3600
  1. clang/
  2. compiler-rt/
  3. debuginfo-tests/
  4. libcxx/
  5. libcxxabi/
  6. lldb/
  7. llvm/
  8. polly/