what does it mean a red filename shown with black background?

Solution 1:

What you have there is a dangling symlink, or a symlink pointing to a file or directory which no longer exists.

A symlink itself really has no filesize, because it isn't a file. Symlinks are stored within the inodes themselves, meaning they have no real contents or size, but are instead pointers to other files on the disk.

The output of file libCLHEP-Exceptions-2.1.3.1.a should reveal where it's pointing to.

Solution 2:

At the first look, it does look like a broken link, but since it is supposed to be a regular file, it might be a file system corruption. Try to do a fsck on the file system and then try to delete this file if it is still there.