diff --git a/lib/cpus/aarch64/cortex_a75_pubsub.c b/lib/cpus/aarch64/cortex_a75_pubsub.c
index 16f62f4..f4ca486 100644
--- a/lib/cpus/aarch64/cortex_a75_pubsub.c
+++ b/lib/cpus/aarch64/cortex_a75_pubsub.c
@@ -12,14 +12,16 @@
 {
 	if (midr_match(CORTEX_A75_MIDR) != 0)
 		cpuamu_context_save(CORTEX_A75_AMU_NR_COUNTERS);
-	return 0;
+
+	return (void *)0;
 }
 
 static void *cortex_a75_context_restore(const void *arg)
 {
 	if (midr_match(CORTEX_A75_MIDR) != 0)
 		cpuamu_context_restore(CORTEX_A75_AMU_NR_COUNTERS);
-	return 0;
+
+	return (void *)0;
 }
 
 SUBSCRIBE_TO_EVENT(psci_suspend_pwrdown_start, cortex_a75_context_save);
diff --git a/lib/cpus/aarch64/cortex_ares_pubsub.c b/lib/cpus/aarch64/cortex_ares_pubsub.c
index c7d850a..9566223 100644
--- a/lib/cpus/aarch64/cortex_ares_pubsub.c
+++ b/lib/cpus/aarch64/cortex_ares_pubsub.c
@@ -12,14 +12,16 @@
 {
 	if (midr_match(CORTEX_ARES_MIDR) != 0)
 		cpuamu_context_save(CORTEX_ARES_AMU_NR_COUNTERS);
-	return 0;
+
+	return (void *)0;
 }
 
 static void *cortex_ares_context_restore(const void *arg)
 {
 	if (midr_match(CORTEX_ARES_MIDR) != 0)
 		cpuamu_context_restore(CORTEX_ARES_AMU_NR_COUNTERS);
-	return 0;
+
+	return (void *)0;
 }
 
 SUBSCRIBE_TO_EVENT(psci_suspend_pwrdown_start, cortex_ares_context_save);
diff --git a/lib/cpus/errata_report.c b/lib/cpus/errata_report.c
index c679336..42603cb 100644
--- a/lib/cpus/errata_report.c
+++ b/lib/cpus/errata_report.c
@@ -12,6 +12,7 @@
 #include <debug.h>
 #include <errata_report.h>
 #include <spinlock.h>
+#include <stdbool.h>
 #include <utils.h>
 
 #ifdef IMAGE_BL1
@@ -35,10 +36,10 @@
  */
 int errata_needs_reporting(spinlock_t *lock, uint32_t *reported)
 {
-	int report_now;
+	bool report_now;
 
 	/* If already reported, return false. */
-	if (*reported)
+	if (*reported != 0U)
 		return 0;
 
 	/*
@@ -46,7 +47,7 @@
 	 * report status to true.
 	 */
 	spin_lock(lock);
-	report_now = !(*reported);
+	report_now = (*reported == 0U);
 	if (report_now)
 		*reported = 1;
 	spin_unlock(lock);
@@ -75,8 +76,8 @@
 
 
 	assert(status < ARRAY_SIZE(errata_status_str));
-	assert(cpu);
-	assert(id);
+	assert(cpu != NULL);
+	assert(id != NULL);
 
 	msg = errata_status_str[status];