The structure is a maybe. The basic building material is stone. Stone doesn't burn, and is not really affected by fire. But there is some iron in the construction of cathedrals of that era, because they were just learning to build open airy places with spans like that, and they often used some iron to stabilize it. This can be damaged if the fire is too hot. Also the mortar between the stones can be weakened. Now there's a good chance that the stone walls will be sufficiently intact. But it's not a certainty.