Linux 2 : What does the file name red with black background indicate

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.

references

https://superuser.com/questions/543397/what-does-it-mean-a-red-filename-shown-with-black-background