Assertion error

vcmiclient: /build/vcmi-vLv9d1/vcmi-0.99+git202011241435~ubuntu20.04.1/AI/BattleAI/AttackPossibility.cpp:121: static AttackPossibility AttackPossibility::evaluate(const BattleAttackInfo&, BattleHex, const HypotheticBattle*): Assertion `u->unitId() != attacker->unitId()’ failed.

That was on a pure AI battle, so i don’t know what exactly happened. The game just freezed, no action possible. The lines directly before this are:

Opening BattleAI
Loaded Battle AI
Battle AI best: greenDragon -> centaur at 104 from 88, affects 1 units: 195 39 0 56
Battle AI best: pegasus -> greenDragon at 88 from 71, affects 1 units: 39 168 0 0
Battle AI best: sharpshooter -> greenDragon at 88 from -1, affects 1 units: 100 0 0 0
Battle AI best: woodElf -> greenDragon at 88 from -1, affects 1 units: 205 0 0 0
Battle AI best: centaur -> greenDragon at 89 from 73, affects 1 units: 36 0 0 0
Battle AI best: skeleton -> greenDragon at 88 from 87, affects 1 units: 1 0 0 0

So it seems it was a battle with a rampart faction hero.