beginning-of-defun-comments bug [was: Re: 26.0.90: mark-defun problem in c-mode]

[Alan Mackenzie]

Hello, Eli.

On Sat, Dec 30, 2017 at 10:34:32 +0000, Alan Mackenzie wrote:
> On Sat, Dec 30, 2017 at 12:30:29 +0200, Eli Zaretskii wrote:
> > > From: zhang cc <address@hidden>
> > > Date: Sat, 30 Dec 2017 09:49:17 +0000

> > > When cursor is in the second function body, mark-defun can’t mark
> > > the second function.

> > "M-x mark-defun" works fine here with your example.  Where exactly
> > should cursor be in the second function body to reproduce the problem?

> I see the error, with point anywhere in the body of the second function.
> Critical seems to be there being no blank line between the functions.

> I think there's a bug in beginning-of-defun-comments, which I'm in the
> middle of edebugging.  It moves point into the first function.

beginning-of-defun-comments has a bug.  On doing M-x
beginning-of-defun-comments from the inside of a function, when there's
no blank lines between it and the previous function, point ends up
inside that previous function, not at the comments which may separate
them.

Perhaps this bug should be fixed before the next Emacs-26 pretest.

-- 
Alan Mackenzie (Nuremberg, Germany).