squid -- confusing results on empty acl declarations

Applying an empty ACL list results in unexpected behavior:
anything will match an empty ACL list. For example,

The meaning of the configuration gets very confusing when
we encounter empty ACLs such as
acl something src “/path/to/empty_file.txt”
http_access allow something somewhere
gets parsed (with warnings) as
http_access allow somewhere
And similarily if you are using proxy_auth acls without
having any auth schemes defined.