bug#24057: 25.1.50; ffap interprets comments beginning with "//" as file path

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Kaushal Modi <kaushal.modi@gmail.com> writes:

> Hi all,
>
> I lived with this bug for a long time and then I lived with a patched 
> ffap-string-at-point for a long time :)
>
> The bug is that if 
>
> (1) a major mode uses "//" as comment start chars, and
> (2) ido-mode is enabled, and
> (3) ffap feature is enabled, and
> (4) user does C-x C-f on a comment like "//foo"
>
> attempt is made to access "//foo" path.

Is possibly a dup of #7229 and/or #8990?