diff --git a/helper/chksum.c b/helper/chksum.c
index b7eef67e..f740618d 100644
--- a/helper/chksum.c
+++ b/helper/chksum.c
@@ -49,7 +49,7 @@ static uint32_t data_seg_sum(uint8_t   *data8_ptr,
 		data_len--;
 	}
 
-	data16_ptr = (uint16_t *)data8_ptr;
+	data16_ptr = (uint16_t *)(void *)data8_ptr;
 
 	/* The following code tries to gain a modest performance enhancement by
 	 * unrolling the normal 16 bits at a time loop eight times.  Even
@@ -216,7 +216,7 @@ static inline int odph_process_l3_hdr(odp_packet_t odp_pkt,
 			ipv6_hdr_ptr = &ipv6_hdr;
 		}
 
-		addrs_ptr        = (uint16_t *)&ipv6_hdr_ptr->src_addr;
+		addrs_ptr        = (uint16_t *)(void *)&ipv6_hdr_ptr->src_addr;
 		addrs_len        = 2 * ODPH_IPV6ADDR_LEN;
 		protocol         = ipv6_hdr_ptr->next_hdr;
 		ipv6_payload_len = odp_be_to_cpu_16(ipv6_hdr_ptr->payload_len);
diff --git a/helper/cuckootable.c b/helper/cuckootable.c
index 83647ec2..396e7f53 100644
--- a/helper/cuckootable.c
+++ b/helper/cuckootable.c
@@ -148,18 +148,6 @@ align32pow2(uint32_t x)
 	return x + 1;
 }
 
-/**
- * Returns true if n is a power of 2
- * @param n
- *     Number to check
- * @return 1 if true, 0 otherwise
- */
-static inline int
-is_power_of_2(uint32_t n)
-{
-	return n && !(n & (n - 1));
-}
-
 odph_table_t
 odph_cuckoo_table_lookup(const char *name)
 {
@@ -209,7 +197,7 @@ odph_cuckoo_table_create(
 	}
 
 	/* Guarantee there's no existing */
-	tbl = (odph_cuckoo_table_impl *)odph_cuckoo_table_lookup(name);
+	tbl = (odph_cuckoo_table_impl *)(void *)odph_cuckoo_table_lookup(name);
 	if (tbl != NULL) {
 		ODPH_DBG("cuckoo hash table %s already exists\n", name);
 		return NULL;
@@ -240,7 +228,7 @@ odph_cuckoo_table_create(
 	/* header of this mem block is the table impl struct,
 	 * then the bucket pool.
 	 */
-	tbl->buckets = (struct cuckoo_table_bucket *)(
+	tbl->buckets = (void *)(
 			(char *)tbl + impl_size);
 
 	/* initialize key-value buffer pool */
@@ -309,17 +297,18 @@ odph_cuckoo_table_create(
 int
 odph_cuckoo_table_destroy(odph_table_t tbl)
 {
-	int ret, i, j;
+	int ret;
 	odph_cuckoo_table_impl *impl = NULL;
 	char pool_name[ODPH_TABLE_NAME_LEN + 3];
 	odp_event_t ev;
 	odp_shm_t shm;
 	odp_pool_t pool;
+	uint32_t i, j;
 
 	if (tbl == NULL)
 		return -1;
 
-	impl = (odph_cuckoo_table_impl *)tbl;
+	impl = (odph_cuckoo_table_impl *)(void *)tbl;
 
 	/* check magic word */
 	if (impl->magicword != ODPH_CUCKOO_TABLE_MAGIC_WORD) {
@@ -578,11 +567,14 @@ cuckoo_table_add_key_with_hash(
 int
 odph_cuckoo_table_put_value(odph_table_t tbl, void *key, void *value)
 {
+	odph_cuckoo_table_impl *impl;
+	int ret;
+
 	if ((tbl == NULL) || (key == NULL))
 		return -EINVAL;
 
-	odph_cuckoo_table_impl *impl = (odph_cuckoo_table_impl *)tbl;
-	int ret = cuckoo_table_add_key_with_hash(
+	impl = (odph_cuckoo_table_impl *)(void *)tbl;
+	ret = cuckoo_table_add_key_with_hash(
 			impl, key, hash(impl, key), value);
 
 	if (ret < 0)
@@ -651,17 +643,16 @@ cuckoo_table_lookup_with_hash(
 	return -ENOENT;
 }
 
-int
-odph_cuckoo_table_get_value(
-		odph_table_t tbl, void *key, void *buffer, uint32_t buffer_size)
+int odph_cuckoo_table_get_value(odph_table_t tbl, void *key,
+				void *buffer, uint32_t buffer_size ODP_UNUSED)
 {
-	if ((tbl == NULL) || (key == NULL))
-		return -EINVAL;
-
-	odph_cuckoo_table_impl *impl = (odph_cuckoo_table_impl *)tbl;
+	odph_cuckoo_table_impl *impl = (odph_cuckoo_table_impl *)(void *)tbl;
 	void *tmp = NULL;
 	int ret;
 
+	if ((tbl == NULL) || (key == NULL))
+		return -EINVAL;
+
 	ret = cuckoo_table_lookup_with_hash(impl, key, hash(impl, key), &tmp);
 
 	if (ret < 0)
@@ -734,13 +725,13 @@ cuckoo_table_del_key_with_hash(
 int
 odph_cuckoo_table_remove_value(odph_table_t tbl, void *key)
 {
+	odph_cuckoo_table_impl *impl = (void *)tbl;
+	int ret;
+
 	if ((tbl == NULL) || (key == NULL))
 		return -EINVAL;
 
-	odph_cuckoo_table_impl *impl = (odph_cuckoo_table_impl *)tbl;
-	int ret =  cuckoo_table_del_key_with_hash(
-			impl, key, hash(impl, key));
-
+	ret = cuckoo_table_del_key_with_hash(impl, key, hash(impl, key));
 	if (ret < 0)
 		return -1;
 
diff --git a/helper/hashtable.c b/helper/hashtable.c
index 983b3da9..1c2b8523 100644
--- a/helper/hashtable.c
+++ b/helper/hashtable.c
@@ -101,9 +101,9 @@ odph_table_t odph_hash_table_create(const char *name, uint32_t capacity,
 	 * the last part is the element node pool
 	 */
 
-	tbl->lock_pool = (odp_rwlock_t *)((char *)tbl
+	tbl->lock_pool = (odp_rwlock_t *)(void *)((char *)tbl
 			+ sizeof(odph_hash_table_imp));
-	tbl->list_head_pool = (odph_list_head *)((char *)tbl->lock_pool
+	tbl->list_head_pool = (odph_list_head *)(void *)((char *)tbl->lock_pool
 			+ ODPH_MAX_BUCKET_NUM * sizeof(odp_rwlock_t));
 
 	node_mem = tbl->init_cap - sizeof(odph_hash_table_imp)
@@ -112,8 +112,9 @@ odph_table_t odph_hash_table_create(const char *name, uint32_t capacity,
 
 	node_num = node_mem / (sizeof(odph_hash_node) + key_size + value_size);
 	tbl->hash_node_num = node_num;
-	tbl->hash_node_pool = (odph_hash_node *)((char *)tbl->list_head_pool
-				+ ODPH_MAX_BUCKET_NUM * sizeof(odph_list_head));
+	tbl->hash_node_pool =
+		(odph_hash_node *)(void *)((char *)tbl->list_head_pool
+		+ ODPH_MAX_BUCKET_NUM * sizeof(odph_list_head));
 
 	/* init every list head and rw lock */
 	for (i = 0; i < ODPH_MAX_BUCKET_NUM; i++) {
@@ -130,8 +131,9 @@ int odph_hash_table_destroy(odph_table_t table)
 	int ret;
 
 	if (table != NULL) {
-		odph_hash_table_imp *hash_tbl = (odph_hash_table_imp *)table;
+		odph_hash_table_imp *hash_tbl;
 
+		hash_tbl = (odph_hash_table_imp *)(void *)table;
 		if (hash_tbl->magicword != ODPH_HASH_TABLE_MAGIC_WORD)
 			return ODPH_FAIL;
 
@@ -164,7 +166,7 @@ odph_table_t odph_hash_table_lookup(const char *name)
  * This hash algorithm is the most simple one, so we choose it as an DEMO
  * User can use any other algorithm, like CRC...
  */
-uint16_t odp_key_hash(void *key, uint32_t key_size)
+static uint16_t odp_key_hash(void *key, uint32_t key_size)
 {
 	register uint32_t hash = 0;
 	uint32_t idx = (key_size == 0 ? 1 : key_size);
@@ -181,18 +183,19 @@ uint16_t odp_key_hash(void *key, uint32_t key_size)
 /**
  * Get an available node from pool
  */
-odph_hash_node *odp_hashnode_take(odph_table_t table)
+static odph_hash_node *hashnode_take(odph_table_t table)
 {
-	odph_hash_table_imp *tbl = (odph_hash_table_imp *)table;
+	odph_hash_table_imp *tbl;
 	uint32_t idx;
 	odph_hash_node *node;
 
+	tbl = (odph_hash_table_imp *)(void *)table;
 	for (idx = 0; idx < tbl->hash_node_num; idx++) {
 		/** notice: memory of one hash_node is
 		 * not only sizeof(odph_hash_node)
 		 * should add the size of Flexible Array
 		 */
-		node = (odph_hash_node *)((char *)tbl->hash_node_pool
+		node = (odph_hash_node *)(void *)((char *)tbl->hash_node_pool
 				+ idx * (sizeof(odph_hash_node)
 						+ tbl->key_size
 						+ tbl->value_size));
@@ -208,13 +211,15 @@ odph_hash_node *odp_hashnode_take(odph_table_t table)
 /**
  * Release an node to the pool
  */
-void odp_hashnode_give(odph_table_t table, odph_hash_node *node)
+static void hashnode_give(odph_table_t table, odph_hash_node *node)
 {
-	odph_hash_table_imp *tbl = (odph_hash_table_imp *)table;
+	odph_hash_table_imp *tbl;
 
 	if (node == NULL)
 		return;
 
+	tbl = (odph_hash_table_imp *)(void *)table;
+
 	odph_list_del(&node->list_node);
 	memset(node, 0,
 	       (sizeof(odph_hash_node) + tbl->key_size + tbl->value_size));
@@ -223,7 +228,7 @@ void odp_hashnode_give(odph_table_t table, odph_hash_node *node)
 /* should make sure the input table exists and is available */
 int odph_hash_put_value(odph_table_t table, void *key, void *value)
 {
-	odph_hash_table_imp *tbl = (odph_hash_table_imp *)table;
+	odph_hash_table_imp *tbl;
 	uint16_t hash = 0;
 	odph_hash_node *node = NULL;
 	char *tmp = NULL;
@@ -231,6 +236,7 @@ int odph_hash_put_value(odph_table_t table, void *key, void *value)
 	if (table == NULL || key == NULL || value == NULL)
 		return ODPH_FAIL;
 
+	tbl = (odph_hash_table_imp *)(void *)table;
 	/* hash value is just the index of the list head in pool */
 	hash = odp_key_hash(key, tbl->key_size);
 
@@ -249,7 +255,7 @@ int odph_hash_put_value(odph_table_t table, void *key, void *value)
 	}
 
 	/*if the key is a new one, get a new hash node form the pool */
-	node = odp_hashnode_take(table);
+	node = hashnode_take(table);
 	if (node == NULL) {
 		odp_rwlock_write_unlock(&tbl->lock_pool[hash]);
 		return ODPH_FAIL;
@@ -271,11 +277,13 @@ int odph_hash_put_value(odph_table_t table, void *key, void *value)
 int odph_hash_get_value(odph_table_t table, void *key, void *buffer,
 			uint32_t buffer_size)
 {
-	odph_hash_table_imp *tbl = (odph_hash_table_imp *)table;
+	odph_hash_table_imp *tbl;
 	uint16_t hash = 0;
 	odph_hash_node *node;
 	char *tmp = NULL;
 
+	tbl = (odph_hash_table_imp *)(void *)table;
+
 	if (table == NULL || key == NULL || buffer == NULL ||
 	    buffer_size < tbl->value_size)
 		return ODPH_FAIL;
@@ -308,13 +316,15 @@ int odph_hash_get_value(odph_table_t table, void *key, void *buffer,
 /* should make sure the input table exists and is available */
 int odph_hash_remove_value(odph_table_t table, void *key)
 {
-	odph_hash_table_imp *tbl = (odph_hash_table_imp *)table;
+	odph_hash_table_imp *tbl;
 	uint16_t hash = 0;
 	odph_hash_node *node;
 
 	if (table == NULL || key == NULL)
 		return ODPH_FAIL;
 
+	tbl = (odph_hash_table_imp *)(void *)table;
+
 	/* hash value is just the index of the list head in pool */
 	hash = odp_key_hash(key, tbl->key_size);
 
@@ -324,7 +334,7 @@ int odph_hash_remove_value(odph_table_t table, void *key)
 			   list_node)
 	{
 		if (memcmp(node->content, key, tbl->key_size) == 0) {
-			odp_hashnode_give(table, node);
+			hashnode_give(table, node);
 			odp_rwlock_write_unlock(&tbl->lock_pool[hash]);
 			return ODPH_SUCCESS;
 		}
diff --git a/helper/iplookuptable.c b/helper/iplookuptable.c
index f6d6f880..e59d1e22 100644
--- a/helper/iplookuptable.c
+++ b/helper/iplookuptable.c
@@ -60,7 +60,7 @@ typedef struct {
 } prefix_entry_t;
 
 #define ENTRY_SIZE (sizeof(prefix_entry_t) + sizeof(odp_buffer_t))
-#define ENTRY_BUFF_ARR(x) ((odp_buffer_t *)((char *)x \
+#define ENTRY_BUFF_ARR(x) ((odp_buffer_t *)(void *)((char *)x \
 			+ sizeof(prefix_entry_t) * ENTRY_NUM_SUBTREE))
 
 /** @internal trie node struct
@@ -434,16 +434,15 @@ odph_iplookup_table_lookup(const char *name)
 	return NULL;
 }
 
-odph_table_t
-odph_iplookup_table_create(
-		const char *name, uint32_t ODP_IGNORED_1,
-		uint32_t ODP_IGNORED_2, uint32_t value_size)
+odph_table_t odph_iplookup_table_create(const char *name,
+					uint32_t p1 ODP_UNUSED,
+					uint32_t p2 ODP_UNUSED,
+					uint32_t value_size)
 {
 	odph_iplookup_table_impl *tbl;
 	odp_shm_t shm_tbl;
 	odp_queue_t queue;
 	odp_queue_param_t qparam;
-
 	unsigned i;
 	uint32_t impl_size, l1_size;
 	char queue_name[ODPH_TABLE_NAME_LEN + 2];
@@ -455,7 +454,7 @@ odph_iplookup_table_create(
 	}
 
 	/* Guarantee there's no existing */
-	tbl = (odph_iplookup_table_impl *)odph_iplookup_table_lookup(name);
+	tbl = (void *)odph_iplookup_table_lookup(name);
 	if (tbl != NULL) {
 		ODPH_DBG("IP prefix table %s already exists\n", name);
 		return NULL;
@@ -482,7 +481,7 @@ odph_iplookup_table_create(
 	/* header of this mem block is the table impl struct,
 	 * then the l1 entries array.
 	 */
-	tbl->l1e = (prefix_entry_t *)((char *)tbl + impl_size);
+	tbl->l1e = (prefix_entry_t *)(void *)((char *)tbl + impl_size);
 	for (i = 0; i < ENTRY_NUM_L1; i++)
 		tbl->l1e[i].nexthop = ODP_BUFFER_INVALID;
 
@@ -528,7 +527,7 @@ odph_iplookup_table_destroy(odph_table_t tbl)
 	if (tbl == NULL)
 		return -1;
 
-	impl = (odph_iplookup_table_impl *)tbl;
+	impl = (odph_iplookup_table_impl *)(void *)tbl;
 
 	/* check magic word */
 	if (impl->magicword != ODPH_IP_LOOKUP_TABLE_MAGIC_WORD) {
@@ -664,15 +663,15 @@ prefix_insert_iter(
 int
 odph_iplookup_table_put_value(odph_table_t tbl, void *key, void *value)
 {
-	if ((tbl == NULL) || (key == NULL) || (value == NULL))
-		return -1;
-
-	odph_iplookup_table_impl *impl = (odph_iplookup_table_impl *)tbl;
+	odph_iplookup_table_impl *impl = (void *)tbl;
 	odph_iplookup_prefix_t *prefix = (odph_iplookup_prefix_t *)key;
 	prefix_entry_t *l1e = NULL;
 	odp_buffer_t nexthop = *((odp_buffer_t *)value);
 	int ret = 0;
 
+	if ((tbl == NULL) || (key == NULL) || (value == NULL))
+		return -1;
+
 	if (prefix->cidr == 0)
 		return -1;
 	prefix->ip = prefix->ip & (0xffffffff << (IP_LENGTH - prefix->cidr));
@@ -704,18 +703,18 @@ odph_iplookup_table_put_value(odph_table_t tbl, void *key, void *value)
 	return ret;
 }
 
-int
-odph_iplookup_table_get_value(
-		odph_table_t tbl, void *key, void *buffer, uint32_t buffer_size)
+int odph_iplookup_table_get_value(odph_table_t tbl, void *key,
+				  void *buffer ODP_UNUSED,
+				  uint32_t buffer_size ODP_UNUSED)
 {
-	if ((tbl == NULL) || (key == NULL) || (buffer == NULL))
-		return -EINVAL;
-
-	odph_iplookup_table_impl *impl = (odph_iplookup_table_impl *)tbl;
+	odph_iplookup_table_impl *impl = (void *)tbl;
 	uint32_t ip = *((uint32_t *)key);
 	prefix_entry_t *entry = &impl->l1e[ip >> 16];
 	odp_buffer_t *buff = (odp_buffer_t *)buffer;
 
+	if ((tbl == NULL) || (key == NULL) || (buffer == NULL))
+		return -EINVAL;
+
 	if (entry == NULL) {
 		ODPH_DBG("failed to get L1 entry.\n");
 		return -1;
@@ -880,14 +879,14 @@ prefix_delete_iter(
 int
 odph_iplookup_table_remove_value(odph_table_t tbl, void *key)
 {
-	if ((tbl == NULL) || (key == NULL))
-		return -EINVAL;
-
-	odph_iplookup_table_impl *impl = (odph_iplookup_table_impl *)tbl;
+	odph_iplookup_table_impl *impl = (void *)tbl;
 	odph_iplookup_prefix_t *prefix = (odph_iplookup_prefix_t *)key;
 	uint32_t ip = prefix->ip;
 	uint8_t cidr = prefix->cidr;
 
+	if ((tbl == NULL) || (key == NULL))
+		return -EINVAL;
+
 	if (prefix->cidr < 0)
 		return -EINVAL;
 
diff --git a/helper/lineartable.c b/helper/lineartable.c
index 89179014..e1a396c1 100644
--- a/helper/lineartable.c
+++ b/helper/lineartable.c
@@ -41,9 +41,10 @@ typedef struct {
  */
 
 odph_table_t odph_linear_table_create(const char *name, uint32_t capacity,
-				      uint32_t ODP_IGNORED, uint32_t value_size)
+				      uint32_t un ODPH_UNUSED,
+				      uint32_t value_size)
 {
-	int idx;
+	uint32_t idx;
 	uint32_t node_num;
 	odp_shm_t shmem;
 	odph_linear_table_imp *tbl;
@@ -90,8 +91,10 @@ odph_table_t odph_linear_table_create(const char *name, uint32_t capacity,
 
 	/* initialize rwlock*/
 	for (idx = 0; idx < tbl->node_sum; idx++) {
-		odp_rwlock_t *lock = (odp_rwlock_t *)((char *)tbl->value_array
-				+ idx * tbl->value_size);
+		odp_rwlock_t *lock;
+
+		lock = (odp_rwlock_t *)(void *)((char *)tbl->value_array
+		       + idx * tbl->value_size);
 		odp_rwlock_init(lock);
 	}
 
@@ -106,7 +109,7 @@ int odph_linear_table_destroy(odph_table_t table)
 	odph_linear_table_imp *linear_tbl = NULL;
 
 	if (table != NULL) {
-		linear_tbl = (odph_linear_table_imp *)table;
+		linear_tbl = (odph_linear_table_imp *)(void *)table;
 
 		/* check magicword, make sure the memory is used by a table */
 		if (linear_tbl->magicword != ODPH_LINEAR_TABLE_MAGIC_WORD)
@@ -142,9 +145,10 @@ odph_table_t odph_linear_table_lookup(const char *name)
 }
 
 /* should make sure the input table exists and is available */
-int odph_lineartable_put_value(odph_table_t table, void *key, void *value)
+static int odph_lineartable_put_value(odph_table_t table,
+				      void *key, void *value)
 {
-	odph_linear_table_imp *tbl = (odph_linear_table_imp *)table;
+	odph_linear_table_imp *tbl;
 	uint32_t ikey = 0;
 	void *entry = NULL;
 	odp_rwlock_t *lock = NULL;
@@ -152,6 +156,7 @@ int odph_lineartable_put_value(odph_table_t table, void *key, void *value)
 	if (table == NULL || key == NULL || value == NULL)
 		return ODPH_FAIL;
 
+	tbl = (odph_linear_table_imp *)(void *)table;
 	ikey = *(uint32_t *)key;
 	if (ikey >= tbl->node_sum)
 		return ODPH_FAIL;
@@ -170,10 +175,11 @@ int odph_lineartable_put_value(odph_table_t table, void *key, void *value)
 }
 
 /* should make sure the input table exists and is available */
-int odph_lineartable_get_value(odph_table_t table, void *key, void *buffer,
-			       uint32_t buffer_size)
+static int odph_lineartable_get_value(odph_table_t table,
+				      void *key, void *buffer,
+				      uint32_t buffer_size ODPH_UNUSED)
 {
-	odph_linear_table_imp *tbl = (odph_linear_table_imp *)table;
+	odph_linear_table_imp *tbl;
 	uint32_t ikey = 0;
 	void *entry = NULL;
 	odp_rwlock_t *lock = NULL;
@@ -181,6 +187,7 @@ int odph_lineartable_get_value(odph_table_t table, void *key, void *buffer,
 	if (table == NULL || key == NULL || buffer == NULL)
 		return ODPH_FAIL;
 
+	tbl = (odph_linear_table_imp *)(void *)table;
 	ikey = *(uint32_t *)key;
 	if (ikey >= tbl->node_sum)
 		return ODPH_FAIL;
diff --git a/helper/threads.c b/helper/threads.c
index fe5d2bde..cb747e5b 100644
--- a/helper/threads.c
+++ b/helper/threads.c
@@ -419,7 +419,7 @@ int odph_parse_options(int argc, char *argv[],
 		{0, 0, 0, 0}
 		};
 
-	static char *helper_short_options = "";
+	static const char *helper_short_options = "";
 
 	/* defaults: */
 	helper_options.proc = false;
