My name is Yuka Takahashi and I'm currently working on bash autocompletion GSoC project.
This is my proposal  and I am planning to make a new flag (I had named "-autocomplete") to handle clang completions.
This flag is internal use only, and I would like to ask you what should be the name of the flag.
Below is the simple description of how -autocompletion flag works for completion (quoted from my proposal):
In this project, the command-line option named “-autocompletion” will be added to clang, and make bash use this flag when autocompleting. When user pushes [tab] in bash, bash will execute “clang whatsoever[tab]-autocompletion” and prints the completion result for “whatsoever”.