Cache file size mismatch on NTFS

[nkr0]

This is quite similar to issue #1332 except that the file system in this case is NTFS.

How to reproduce

Install ccache and compile on windows with NTFS file system. ccache -sx should show roughly the same value for Cache size and Total data and cleanup when Cache size exceeds limit.

Actual behavior

Unlike #1332 , Cache size shows a non-zero value. But still much less than Total data. Checking properties of the folder, Total data seems to be more accurate. Cache is not cleaned because Cache size is less than max limit.

Expected behavior

Both values match on linux and cleanup keeps cache size under limit.

Environment

ccache version 4.8.3 with msvc 2019 on windows
ccache version 4.5.1 with gcc 11 on linux