Comment # 3 on bug 889319 from Dr. Werner Fink

Btw:

  d136:graphviz # complete -r ls
  d136:graphviz # complete -p ls
  -bash: complete: ls: no completion specification
  d136:graphviz # ls *.spec<TAB><TAB>

also shows nothing, that is it is not a problem of bash-completion only but
bash never ever had done this. In other words: this requires an further shell
function within bash-completion to be able to expand `*.suffix<TAB>'.  This is
not done within a few minutes as also all side effects has to be tested.