diff --git a/src/common/printf.c b/src/common/printf.c
index 93dc00d387..993340be6a 100644
--- a/src/common/printf.c
+++ b/src/common/printf.c
@@ -45,7 +45,7 @@
 #include "typeconversion.h"
 #endif
 
-serialPort_t *printfSerialPort;
+static serialPort_t *printfSerialPort;
 
 #ifdef REQUIRE_CC_ARM_PRINTF_SUPPORT
 
diff --git a/src/drivers/pwm_output.c b/src/drivers/pwm_output.c
index 4a340c7cce..0099d9e225 100644
--- a/src/drivers/pwm_output.c
+++ b/src/drivers/pwm_output.c
@@ -28,7 +28,7 @@ typedef struct {
     pwmWriteFuncPtr pwmWritePtr;
 } pwmOutputPort_t;
 
-pwmOutputPort_t pwmOutputPorts[MAX_PWM_OUTPUT_PORTS];
+static pwmOutputPort_t pwmOutputPorts[MAX_PWM_OUTPUT_PORTS];
 
 static pwmOutputPort_t *motors[MAX_PWM_MOTORS];
 static pwmOutputPort_t *servos[MAX_PWM_SERVOS];
diff --git a/src/drivers/timer_common.c b/src/drivers/timer_common.c
index 91c8e90b46..2f6b1629ed 100644
--- a/src/drivers/timer_common.c
+++ b/src/drivers/timer_common.c
@@ -146,7 +146,7 @@ typedef struct timerConfig_s {
     uint8_t reference;
 } timerConfig_t;
 
-timerConfig_t timerConfig[MAX_TIMERS * CC_CHANNELS_PER_TIMER];
+static timerConfig_t timerConfig[MAX_TIMERS * CC_CHANNELS_PER_TIMER];
 
 static uint8_t lookupTimerIndex(const TIM_TypeDef *tim)
 {
diff --git a/src/sensors_acceleration.c b/src/sensors_acceleration.c
index 1c7b7832e5..e2abd098ea 100644
--- a/src/sensors_acceleration.c
+++ b/src/sensors_acceleration.c
@@ -28,7 +28,7 @@ extern bool AccInflightCalibrationMeasurementDone;
 extern bool AccInflightCalibrationSavetoEEProm;
 extern bool AccInflightCalibrationActive;
 
-int16_flightDynamicsTrims_t *accelerationTrims;
+static int16_flightDynamicsTrims_t *accelerationTrims;
 
 void accSetCalibrationCycles(uint16_t calibrationCyclesRequired)
 {