base packages and subdirs with no regular files

Hi All!

I use base package for more then a year now. It works mostly fine.
However today I noticed that (some?) blank subdirectories are not
removed while updating:
---
% LANG=C ls -l /usr/lib/clang
drwxr-xr-x  4 root  wheel  4 Dec 22  2016 3.9.1
drwxr-xr-x  4 root  wheel  4 Mar  3  2017 4.0.0
drwxr-xr-x  4 root  wheel  4 Aug 28 14:50 5.0.0
drwxr-xr-x  4 root  wheel  4 Dec  8 13:09 5.0.1
---

All previous (to 5.0.1) clang version dirs contain only directories,
no regular files:
---
% LANG=C ls -l /usr/lib/clang/5.0.0
total 25
drwxr-xr-x  3 root  wheel  3 Dec  8 13:09 include
drwxr-xr-x  3 root  wheel  3 Aug 28 14:50 lib

% LANG=C ls -l /usr/lib/clang/5.0.0/include
total 1
drwxr-xr-x  2 root  wheel  2 Dec  8 13:09 sanitizer

% LANG=C ls -l /usr/lib/clang/5.0.0/include/sanitizer
total 0
---

I use my personal base package builder and just "pkg upgrade"
for, well, upgrades.

-- 
WBR, bsam