2" PVC Crack!

I didn't think you could break PVC so easily, but during a bath remodel, this fitting cracked! It's the vent pipe on top of the main soil stack. Needless to say it does not carry water. Do you think I can get away with sealing the crack somehow? Otherwise this sucker is really buried and I'll be opening a wall and in hell. Thanks!

The correct way is to replace the broken piece.

Voletl gave the "right" answer. Period.
Any other answer is based on putting this into the perspective of function and permanence.
The plumbing vent is a significant part of the system and leaking of sewer gas is very serious stuff.
That said, if this crack would not be buried (ie accessable), then perhaps you could use an epoxy compatible with PVC (like JB Weld plastic weld) and apply two stainless steel hose clamps to reinforce the strained joint.
Then, water test the stack to insure it holds.
That would be the only way to prove it is functional and safe.