Security fix to marking.
We had to reason backward from the end of the string, which is introducing ambiguity. Instead, we now point at an earlier point, before the string, and let the string continue up to an inluding the NUL terminator.
We had to reason backward from the end of the string, which is introducing ambiguity. Instead, we now point at an earlier point, before the string, and let the string continue up to an inluding the NUL terminator.