ZEND_API HashTable* ZEND_FASTCALL zend_array_dup(HashTable *source)
{
	uint32_t idx;
	HashTable *target;

	IS_CONSISTENT(source);

	ALLOC_HASHTABLE(target);
	GC_REFCOUNT(target) = 1;
	GC_TYPE_INFO(target) = IS_ARRAY;

	target->nTableSize = source->nTableSize;
	target->pDestructor = source->pDestructor;

	if (source->nNumUsed == 0) {
		target->u.flags = (source->u.flags & ~(HASH_FLAG_INITIALIZED|HASH_FLAG_PACKED|HASH_FLAG_PERSISTENT|ZEND_HASH_APPLY_COUNT_MASK)) | HASH_FLAG_APPLY_PROTECTION | HASH_FLAG_STATIC_KEYS;
		target->nTableMask = HT_MIN_MASK;
		target->nNumUsed = 0;
		target->nNumOfElements = 0;
		target->nNextFreeElement = 0;
		target->nInternalPointer = HT_INVALID_IDX;
		HT_SET_DATA_ADDR(target, &uninitialized_bucket);
	} else if (GC_FLAGS(source) & IS_ARRAY_IMMUTABLE) {
		target->u.flags = (source->u.flags & ~HASH_FLAG_PERSISTENT) | HASH_FLAG_APPLY_PROTECTION;
		target->nTableMask = source->nTableMask;
		target->nNumUsed = source->nNumUsed;
		target->nNumOfElements = source->nNumOfElements;
		target->nNextFreeElement = source->nNextFreeElement;
		HT_SET_DATA_ADDR(target, emalloc(HT_SIZE(target)));
		target->nInternalPointer = source->nInternalPointer;
		memcpy(HT_GET_DATA_ADDR(target), HT_GET_DATA_ADDR(source), HT_USED_SIZE(source));
		if (target->nNumOfElements > 0 &&
		    target->nInternalPointer == HT_INVALID_IDX) {
			idx = 0;
			while (Z_TYPE(target->arData[idx].val) == IS_UNDEF) {
				idx++;
			}
			target->nInternalPointer = idx;
		}
	} else if (source->u.flags & HASH_FLAG_PACKED) {
		target->u.flags = (source->u.flags & ~(HASH_FLAG_PERSISTENT|ZEND_HASH_APPLY_COUNT_MASK)) | HASH_FLAG_APPLY_PROTECTION;
		target->nTableMask = source->nTableMask;
		target->nNumUsed = source->nNumUsed;
		target->nNumOfElements = source->nNumOfElements;
		target->nNextFreeElement = source->nNextFreeElement;
		HT_SET_DATA_ADDR(target, emalloc(HT_SIZE(target)));
		target->nInternalPointer = source->nInternalPointer;
		HT_HASH_RESET_PACKED(target);

		if (target->nNumUsed == target->nNumOfElements) {
			zend_array_dup_packed_elements(source, target, 0);
		} else {
			zend_array_dup_packed_elements(source, target, 1);
		}
		if (target->nNumOfElements > 0 &&
		    target->nInternalPointer == HT_INVALID_IDX) {
			idx = 0;
			while (Z_TYPE(target->arData[idx].val) == IS_UNDEF) {
				idx++;
			}
			target->nInternalPointer = idx;
		}
	} else {
		target->u.flags = (source->u.flags & ~(HASH_FLAG_PERSISTENT|ZEND_HASH_APPLY_COUNT_MASK)) | HASH_FLAG_APPLY_PROTECTION;
		target->nTableMask = source->nTableMask;
		target->nNextFreeElement = source->nNextFreeElement;
		target->nInternalPointer = source->nInternalPointer;

		HT_SET_DATA_ADDR(target, emalloc(HT_SIZE(target)));
		HT_HASH_RESET(target);

		if (target->u.flags & HASH_FLAG_STATIC_KEYS) {
			if (source->nNumUsed == source->nNumOfElements) {
				idx = zend_array_dup_elements(source, target, 1, 0);
			} else {
				idx = zend_array_dup_elements(source, target, 1, 1);
			}
		} else {
			if (source->nNumUsed == source->nNumOfElements) {
				idx = zend_array_dup_elements(source, target, 0, 0);
			} else {
				idx = zend_array_dup_elements(source, target, 0, 1);
			}
		}
		target->nNumUsed = idx;
		target->nNumOfElements = idx;
		if (idx > 0 && target->nInternalPointer == HT_INVALID_IDX) {
			target->nInternalPointer = 0;
		}
	}
	return target;
}

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.