static void ZEND_FASTCALL zend_hash_do_resize(HashTable *ht)
{

	IS_CONSISTENT(ht);
	HT_ASSERT(GC_REFCOUNT(ht) == 1);

	if (ht->nNumUsed > ht->nNumOfElements + (ht->nNumOfElements >> 5)) { /* additional term is there to amortize the cost of compaction */
		HANDLE_BLOCK_INTERRUPTIONS();
		zend_hash_rehash(ht);
		HANDLE_UNBLOCK_INTERRUPTIONS();
	} else if (ht->nTableSize < HT_MAX_SIZE) {	/* Let's double the table size */
		void *new_data, *old_data = HT_GET_DATA_ADDR(ht);
		uint32_t nSize = ht->nTableSize + ht->nTableSize;
		Bucket *old_buckets = ht->arData;

		HANDLE_BLOCK_INTERRUPTIONS();
		new_data = pemalloc(HT_SIZE_EX(nSize, -nSize), ht->u.flags & HASH_FLAG_PERSISTENT);
		ht->nTableSize = nSize;
		ht->nTableMask = -ht->nTableSize;
		HT_SET_DATA_ADDR(ht, new_data);
		memcpy(ht->arData, old_buckets, sizeof(Bucket) * ht->nNumUsed);
		pefree(old_data, ht->u.flags & HASH_FLAG_PERSISTENT);
		zend_hash_rehash(ht);
		HANDLE_UNBLOCK_INTERRUPTIONS();
	} else {
		zend_error_noreturn(E_ERROR, "Possible integer overflow in memory allocation (%zu * %zu + %zu)", ht->nTableSize * 2, sizeof(Bucket) + sizeof(uint32_t), sizeof(Bucket));
	}
}

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.