Comment # 5 on bug 903362 from Dr. Werner Fink

If it does not happen with root the bug is not in bash nor in bash-completion
but IMHO within your personal ~/.profile and/or ~/.bashrc

Beside this fc *is* a bash builtin and used with the bash command line history.

The normal complete for this builtin is here

   linux:~ # complete -p | grep fc
   complete -F _minimal fc
   linux:~ # set | sed -rn '/^_minimal/,/^}/p'
   _minimal () 
   { 
       local cur prev words cword split;
       _init_completion -s || return;
       $split && return;
       _filedir
   }

... maybe you have overriden one of the shell functions like _minimal,
_init_completion, or _filedir ... or any other shell function used therein.

It is up on you to debug this on your own as I'm not able to reproduce this.