How does Overchannel work with Cantrips?

Question

On Page 32 of the D&D 5e Basic rules we have the following 14th level Wizard Ability.

Overchannel

Starting at 14th level, you can increase the power of your simpler spells. When you cast a wizard spell of 5th level or lower that deals damage, you can deal maximum damage with that spell. The first time you do so, you suffer no adverse effect. If you use this feature again before you finish a long rest, you take 2d12 necrotic damage for each level of the spell, immediately after you cast it. Each time you use this feature again before finishing a long rest, the necrotic damage per spell level increases by 1d12. This damage ignores resistance and immunity

Since Cantrips are Zero level spells.

Page 78

A cantrip’s spell level is 0.

How do cantrips work with the overchannel ability?

Answer 1

There is nothing in the text of overchannel that would prohibit you from doing so. And as such, by the book there would be no damage from maximizing the damage.

However, we do have this from Mike Mearls' twitter feed:

Mike Mearls @mikemearls
Overchannel questions: Not intended to work with cantrips, but it works out if you increase the damage by 1d12 per cantrip
7 July 2014 - 9:30 am

As of June of 2015, the 5e Errata from Wizards of the Coast confirms that overchannel doesn't work with cantrips.

Answer 2

You can't use Overchannel with cantrips. The newly released errata for the PHB specified this:

Overchannel (p. 118). The feature doesn’t benefit cantrips.