diff --git a/hw/mcu/native/src/hal_timer.c b/hw/mcu/native/src/hal_timer.c
index 098ab8ddd5..77d3d0efea 100644
--- a/hw/mcu/native/src/hal_timer.c
+++ b/hw/mcu/native/src/hal_timer.c
@@ -331,7 +331,7 @@ int
 hal_timer_stop(struct hal_timer *timer)
 {
     struct native_timer *nt;
-    struct hal_timer *ht;
+    struct hal_timer *ht = NULL;
     int reset_ocmp;
     os_sr_t sr;
 
diff --git a/hw/mcu/nordic/nrf51xxx/src/hal_timer.c b/hw/mcu/nordic/nrf51xxx/src/hal_timer.c
index a99be65cb1..abcd7a9a47 100644
--- a/hw/mcu/nordic/nrf51xxx/src/hal_timer.c
+++ b/hw/mcu/nordic/nrf51xxx/src/hal_timer.c
@@ -939,7 +939,7 @@ hal_timer_stop(struct hal_timer *timer)
 {
     uint32_t ctx;
     int reset_ocmp;
-    struct hal_timer *entry;
+    struct hal_timer *entry = NULL;
     struct nrf51_hal_timer *bsptimer;
 
     if (timer == NULL) {
diff --git a/hw/mcu/nordic/nrf52xxx/src/hal_timer.c b/hw/mcu/nordic/nrf52xxx/src/hal_timer.c
index fc6fe834d1..75dec3c382 100644
--- a/hw/mcu/nordic/nrf52xxx/src/hal_timer.c
+++ b/hw/mcu/nordic/nrf52xxx/src/hal_timer.c
@@ -908,7 +908,7 @@ hal_timer_stop(struct hal_timer *timer)
 {
     uint32_t ctx;
     int reset_ocmp;
-    struct hal_timer *entry;
+    struct hal_timer *entry = NULL;
     struct nrf52_hal_timer *bsptimer;
 
     if (timer == NULL) {
diff --git a/hw/mcu/nordic/nrf5340/src/hal_timer.c b/hw/mcu/nordic/nrf5340/src/hal_timer.c
index cdc6c1ed0e..082567b9c4 100644
--- a/hw/mcu/nordic/nrf5340/src/hal_timer.c
+++ b/hw/mcu/nordic/nrf5340/src/hal_timer.c
@@ -860,7 +860,7 @@ hal_timer_stop(struct hal_timer *timer)
 {
     uint32_t ctx;
     int reset_ocmp;
-    struct hal_timer *entry;
+    struct hal_timer *entry = NULL;
     struct nrf5340_hal_timer *bsptimer;
 
     if (timer == NULL) {
diff --git a/hw/mcu/nordic/nrf5340_net/src/hal_timer.c b/hw/mcu/nordic/nrf5340_net/src/hal_timer.c
index 06884c61b3..9f6701520e 100644
--- a/hw/mcu/nordic/nrf5340_net/src/hal_timer.c
+++ b/hw/mcu/nordic/nrf5340_net/src/hal_timer.c
@@ -860,7 +860,7 @@ hal_timer_stop(struct hal_timer *timer)
 {
     uint32_t ctx;
     int reset_ocmp;
-    struct hal_timer *entry;
+    struct hal_timer *entry = NULL;
     struct nrf5340_hal_timer *bsptimer;
 
     if (timer == NULL) {
diff --git a/hw/mcu/nordic/nrf91xx/src/hal_timer.c b/hw/mcu/nordic/nrf91xx/src/hal_timer.c
index 61f87a10ed..5547a32818 100644
--- a/hw/mcu/nordic/nrf91xx/src/hal_timer.c
+++ b/hw/mcu/nordic/nrf91xx/src/hal_timer.c
@@ -894,7 +894,7 @@ hal_timer_stop(struct hal_timer *timer)
 {
     uint32_t ctx;
     int reset_ocmp;
-    struct hal_timer *entry;
+    struct hal_timer *entry = NULL;
     struct nrf91_hal_timer *bsptimer;
 
     if (timer == NULL) {
diff --git a/hw/mcu/nxp/kinetis/src/hal_timer.c b/hw/mcu/nxp/kinetis/src/hal_timer.c
index 4fadd01a2c..58cc02e3ee 100644
--- a/hw/mcu/nxp/kinetis/src/hal_timer.c
+++ b/hw/mcu/nxp/kinetis/src/hal_timer.c
@@ -405,7 +405,7 @@ int
 hal_timer_stop(struct hal_timer *timer)
 {
     struct kinetis_hal_tmr *tmr;
-    struct hal_timer *entry;
+    struct hal_timer *entry = NULL;
     bool reset_period;
     os_sr_t sr;
 
diff --git a/hw/mcu/stm/stm32_common/src/hal_timer.c b/hw/mcu/stm/stm32_common/src/hal_timer.c
index e5f4ed7ac9..b7c2206746 100644
--- a/hw/mcu/stm/stm32_common/src/hal_timer.c
+++ b/hw/mcu/stm/stm32_common/src/hal_timer.c
@@ -784,7 +784,7 @@ int
 hal_timer_stop(struct hal_timer *timer)
 {
     struct stm32_hal_tmr *tmr;
-    struct hal_timer *ht;
+    struct hal_timer *ht = NULL;
     int sr;
     int reset_ocmp;