bash completion on 4.0 broken?

[Stephen Boyd <bebarino@gmail.com>]

When I try

    git show --pretty=<TAB><TAB>

I get a list of filenames and not the list of pretty formats.

I've debugged a little and see that the cur variable in _git_show () is 
set to '=' when it should be '--pretty='. So it looks like something is 
causing the command line to be split weirdly. Looking at the bash 
NEWS[1] for 4.0 I see

i.  The programmable completion code now uses the same set of characters as
    readline when breaking the command line into a list of words.


which causes me to believe this is why it's broken now. I've tried 
removing '=' from COMP_WORDBREAKS and that shows the list of formats 
correctly, but then causes the entire '--pretty=' to be replaced with 
the selected format.

Anyone else seeing the same problem or is my system just b0rked?

$ bash --version
GNU bash, version 4.0.35(2)-release (x86_64-pc-linux-gnu)

References:
[1] http://tiswww.case.edu/php/chet/bash/NEWS