Yes, you'll need 2017 Form 8606 to be included with your 2017 tax return.
The instructions at the bottom of page 5 of the 2016 Instructions for Form 8606 are explicitly for a return of excess contribution from a *traditional* IRA, not a Roth IRA.
A distribution made from your Roth IRA after the due date of your tax return is a *regular* distribution. If you have not reached age 59½ by the time you make the distribution, this regular distribution *must* be reported on Form 8606 Part III. (I assume that some of your contribution for 2012 was not an excess contribution or your made contributions for years prior to 2012, so at least you have met the 5-year holding period for the distribution to be a qualified distribution, leaving only the age 59½ requirement.)
