cc-mode auto indent, topmost-intro-cont vs. member-init-intro

[Brian Fallik]

Hi,

I'm trying to diagnose a recent issue I encountered after upgrading
from Fedora 16 (emacs 23.1) to 17 (emacs 24.1).  After upgrading,
emacs is formatting the ctor member initializer list incorrectly.  C-c
C-s over the ':' character starting the list outputs
'topmost-intro-cont'.  When I press <tab> emacs reformats the line to
start from column 0:
        ...
        Type last_ctor_arg)
: mXid(id),
instead of c-basic-offset like it used to:
        ...
        Type last_ctor_arg)
    : mXid(id),

Even more confusing is that I was able to avoid the problem by
removing (or commenting out) ctor arguments.  It's as though the
parser gives up after a certain number or text size of the args.

Here's the a snippet of the original code:  http://pastebin.com/i2rR2zDZ

I'm not sure if this is a bug, a misconfiguration, or something else
but the behavior seems odd to me.

Thanks,
brian