Is it possible to turn off abbreviation in
Long option names may be abbreviated if the abbreviation is unique or is an exact match for >some defined option.
It appears there isn't a way to disable the abbreviation feature. You aren't alone in wishing for this feature. See: http://sourceware.org/bugzilla/show_bug.cgi?id=6863
Unfortunately, It seems the glibc developers don't want the option as the bug report linked above was resolved with "WONTFIX". You may be out of luck here :-\