diff --git a/include/logging/log_msg.h b/include/logging/log_msg.h
index 9292b49dbff..6d99c4a6b5e 100644
--- a/include/logging/log_msg.h
+++ b/include/logging/log_msg.h
@@ -347,7 +347,7 @@ static inline struct log_msg *_log_msg_std_alloc(void)
 {
 	struct  log_msg *msg = (struct  log_msg *)log_msg_chunk_alloc();
 
-	if (msg) {
+	if (msg != NULL) {
 		/* all fields reset to 0, reference counter to 1 */
 		msg->hdr.ref_cnt = 1;
 		msg->hdr.params.raw = 0;
diff --git a/kernel/include/ksched.h b/kernel/include/ksched.h
index f93e5bc4596..f950e961c0f 100644
--- a/kernel/include/ksched.h
+++ b/kernel/include/ksched.h
@@ -240,7 +240,7 @@ static inline void _ready_one_thread(_wait_q_t *wq)
 {
 	struct k_thread *th = _unpend_first_thread(wq);
 
-	if (th) {
+	if (th != NULL) {
 		_ready_thread(th);
 	}
 }
@@ -285,7 +285,7 @@ static inline struct k_thread *_unpend1_no_timeout(_wait_q_t *wait_q)
 {
 	struct k_thread *thread = _find_first_thread_to_unpend(wait_q, NULL);
 
-	if (thread) {
+	if (thread != NULL) {
 		_unpend_thread_no_timeout(thread);
 	}
 
diff --git a/kernel/include/timeout_q.h b/kernel/include/timeout_q.h
index e40234e12db..ad6cf0b5e61 100644
--- a/kernel/include/timeout_q.h
+++ b/kernel/include/timeout_q.h
@@ -68,7 +68,7 @@ _init_thread_timeout(struct _thread_base *thread_base)
 static inline void _unpend_thread_timing_out(struct k_thread *thread,
 					     struct _timeout *timeout_obj)
 {
-	if (timeout_obj->wait_q) {
+	if (timeout_obj->wait_q != NULL) {
 		_unpend_thread_no_timeout(thread);
 		thread->base.timeout.wait_q = NULL;
 	}
@@ -88,14 +88,14 @@ static inline void _handle_one_expired_timeout(struct _timeout *timeout)
 	timeout->delta_ticks_from_prev = _INACTIVE;
 
 	K_DEBUG("timeout %p\n", timeout);
-	if (thread) {
+	if (thread != NULL) {
 		_unpend_thread_timing_out(thread, timeout);
 		_mark_thread_as_started(thread);
 		_ready_thread(thread);
 		irq_unlock(key);
 	} else {
 		irq_unlock(key);
-		if (timeout->func) {
+		if (timeout->func != NULL) {
 			timeout->func(timeout);
 		}
 	}
diff --git a/kernel/mem_slab.c b/kernel/mem_slab.c
index 8a845219338..76b009aa963 100644
--- a/kernel/mem_slab.c
+++ b/kernel/mem_slab.c
@@ -117,7 +117,7 @@ void k_mem_slab_free(struct k_mem_slab *slab, void **mem)
 	int key = irq_lock();
 	struct k_thread *pending_thread = _unpend_first_thread(&slab->wait_q);
 
-	if (pending_thread) {
+	if (pending_thread != NULL) {
 		_set_thread_return_value_with_data(pending_thread, 0, *mem);
 		_ready_thread(pending_thread);
 		_reschedule(key);
diff --git a/kernel/mempool.c b/kernel/mempool.c
index 6b6a140bf62..61d48c73a71 100644
--- a/kernel/mempool.c
+++ b/kernel/mempool.c
@@ -209,7 +209,7 @@ void *z_thread_malloc(size_t size)
 {
 	void *ret;
 
-	if (_current->resource_pool) {
+	if (_current->resource_pool != NULL) {
 		ret = k_mem_pool_malloc(_current->resource_pool, size);
 	} else {
 		ret = NULL;
diff --git a/kernel/msg_q.c b/kernel/msg_q.c
index 4cbf0a3784a..6b2da3a980d 100644
--- a/kernel/msg_q.c
+++ b/kernel/msg_q.c
@@ -76,7 +76,7 @@ int _impl_k_msgq_alloc_init(struct k_msgq *q, size_t msg_size,
 		ret = -EINVAL;
 	} else {
 		buffer = z_thread_malloc(total_size);
-		if (buffer) {
+		if (buffer != NULL) {
 			k_msgq_init(q, buffer, msg_size, max_msgs);
 			q->flags = K_MSGQ_FLAG_ALLOC;
 			ret = 0;
@@ -119,7 +119,7 @@ int _impl_k_msgq_put(struct k_msgq *q, void *data, s32_t timeout)
 	if (q->used_msgs < q->max_msgs) {
 		/* message queue isn't full */
 		pending_thread = _unpend_first_thread(&q->wait_q);
-		if (pending_thread) {
+		if (pending_thread != NULL) {
 			/* give message to waiting thread */
 			(void)memcpy(pending_thread->base.swap_data, data,
 			       q->msg_size);
diff --git a/kernel/pipes.c b/kernel/pipes.c
index c30e80e0dcc..66333090368 100644
--- a/kernel/pipes.c
+++ b/kernel/pipes.c
@@ -347,7 +347,7 @@ static bool pipe_xfer_prepare(sys_dlist_t      *xfer_list,
 	sys_dlist_init(xfer_list);
 	num_bytes = 0;
 
-	while ((thread = _waitq_head(wait_q))) {
+	while ((thread = _waitq_head(wait_q)) != NULL) {
 		desc = (struct k_pipe_desc *)thread->base.swap_data;
 		num_bytes += desc->bytes_to_xfer;
 
diff --git a/kernel/sem.c b/kernel/sem.c
index eb32515719e..3a0c38f2d10 100644
--- a/kernel/sem.c
+++ b/kernel/sem.c
@@ -101,7 +101,7 @@ static void do_sem_give(struct k_sem *sem)
 {
 	struct k_thread *thread = _unpend_first_thread(&sem->wait_q);
 
-	if (thread) {
+	if (thread != NULL) {
 		_ready_thread(thread);
 		_set_thread_return_value(thread, 0);
 	} else {
diff --git a/kernel/stack.c b/kernel/stack.c
index 8088659a966..fccb5a8364f 100644
--- a/kernel/stack.c
+++ b/kernel/stack.c
@@ -62,7 +62,7 @@ int _impl_k_stack_alloc_init(struct k_stack *stack, unsigned int num_entries)
 	int ret;
 
 	buffer = z_thread_malloc(num_entries);
-	if (buffer) {
+	if (buffer != NULL) {
 		k_stack_init(stack, buffer, num_entries);
 		stack->flags = K_STACK_FLAG_ALLOC;
 		ret = 0;
@@ -105,7 +105,7 @@ void _impl_k_stack_push(struct k_stack *stack, u32_t data)
 
 	first_pending_thread = _unpend_first_thread(&stack->wait_q);
 
-	if (first_pending_thread) {
+	if (first_pending_thread != NULL) {
 		_ready_thread(first_pending_thread);
 
 		_set_thread_return_value_with_data(first_pending_thread,
diff --git a/kernel/thread.c b/kernel/thread.c
index 9042920e963..606380b2675 100644
--- a/kernel/thread.c
+++ b/kernel/thread.c
@@ -394,7 +394,7 @@ void _setup_new_thread(struct k_thread *new_thread,
 #endif
 #ifdef CONFIG_USERSPACE
 	/* New threads inherit any memory domain membership by the parent */
-	if (_current->mem_domain_info.mem_domain) {
+	if (_current->mem_domain_info.mem_domain != NULL) {
 		k_mem_domain_add_thread(_current->mem_domain_info.mem_domain,
 					new_thread);
 	}
diff --git a/kernel/userspace.c b/kernel/userspace.c
index f5c45a70e10..a1b6dfc31d1 100644
--- a/kernel/userspace.c
+++ b/kernel/userspace.c
@@ -513,7 +513,8 @@ void k_object_access_all_grant(void *object)
 int _k_object_validate(struct _k_object *ko, enum k_objects otype,
 		       enum _obj_init_check init)
 {
-	if (unlikely(!ko || (otype != K_OBJ_ANY && ko->type != otype))) {
+	if (unlikely((ko == NULL) ||
+		(otype != K_OBJ_ANY && ko->type != otype))) {
 		return -EBADF;
 	}