diff --git a/cpu/atmega_common/periph/rtt.c b/cpu/atmega_common/periph/rtt.c
index 0719117c34..ffce508d40 100644
--- a/cpu/atmega_common/periph/rtt.c
+++ b/cpu/atmega_common/periph/rtt.c
@@ -42,6 +42,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <avr/interrupt.h>
 
 #include "byteorder.h"
diff --git a/cpu/atmega_common/periph/timer.c b/cpu/atmega_common/periph/timer.c
index eadfc4ddc5..1fab2f62ee 100644
--- a/cpu/atmega_common/periph/timer.c
+++ b/cpu/atmega_common/periph/timer.c
@@ -20,6 +20,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <avr/interrupt.h>
 
 #include "board.h"
diff --git a/cpu/atmega_common/periph/wdt.c b/cpu/atmega_common/periph/wdt.c
index 4debf87926..5c9925dab9 100644
--- a/cpu/atmega_common/periph/wdt.c
+++ b/cpu/atmega_common/periph/wdt.c
@@ -19,6 +19,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "periph/pm.h"
 #include "periph/wdt.h"
diff --git a/cpu/cc2538/periph/gpio.c b/cpu/cc2538/periph/gpio.c
index 464921dcad..ebabb742cf 100644
--- a/cpu/cc2538/periph/gpio.c
+++ b/cpu/cc2538/periph/gpio.c
@@ -21,6 +21,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stdint.h>
 
 #include "cpu.h"
diff --git a/cpu/cc2538/periph/rtt.c b/cpu/cc2538/periph/rtt.c
index 98be86fa0f..6177b6dc18 100644
--- a/cpu/cc2538/periph/rtt.c
+++ b/cpu/cc2538/periph/rtt.c
@@ -19,6 +19,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stdint.h>
 
 #include "cpu.h"
diff --git a/cpu/cc2538/periph/uart.c b/cpu/cc2538/periph/uart.c
index a1c160430e..c4e894b0dd 100644
--- a/cpu/cc2538/periph/uart.c
+++ b/cpu/cc2538/periph/uart.c
@@ -20,6 +20,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stddef.h>
 
 #include "board.h"
diff --git a/cpu/cc2538/periph/wdt.c b/cpu/cc2538/periph/wdt.c
index cd46fc2b65..2e7c7edbcd 100644
--- a/cpu/cc2538/periph/wdt.c
+++ b/cpu/cc2538/periph/wdt.c
@@ -20,6 +20,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cc2538.h"
 #include "periph/wdt.h"
 
diff --git a/cpu/cc2538/radio/cc2538_rf_radio_ops.c b/cpu/cc2538/radio/cc2538_rf_radio_ops.c
index 36863ea493..cd250392db 100644
--- a/cpu/cc2538/radio/cc2538_rf_radio_ops.c
+++ b/cpu/cc2538/radio/cc2538_rf_radio_ops.c
@@ -19,6 +19,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <errno.h>
 #include <stdio.h>
 
diff --git a/cpu/cc26xx_cc13xx/periph/uart.c b/cpu/cc26xx_cc13xx/periph/uart.c
index 12f70891f0..18965a68ad 100644
--- a/cpu/cc26xx_cc13xx/periph/uart.c
+++ b/cpu/cc26xx_cc13xx/periph/uart.c
@@ -22,6 +22,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "periph/uart.h"
 #include "periph_conf.h"
diff --git a/cpu/efm32/periph/adc.c b/cpu/efm32/periph/adc.c
index c743f23cca..536a063e0e 100644
--- a/cpu/efm32/periph/adc.c
+++ b/cpu/efm32/periph/adc.c
@@ -19,6 +19,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "mutex.h"
 
diff --git a/cpu/efm32/periph/pwm.c b/cpu/efm32/periph/pwm.c
index 70d00560f5..f8c2f2432e 100644
--- a/cpu/efm32/periph/pwm.c
+++ b/cpu/efm32/periph/pwm.c
@@ -17,6 +17,8 @@
  * @author      Bas Stottelaar <basstottelaar@gmail.com>
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 
 #include "periph_conf.h"
diff --git a/cpu/efm32/periph/spi.c b/cpu/efm32/periph/spi.c
index 299ad009d1..2b7ab3e7f5 100644
--- a/cpu/efm32/periph/spi.c
+++ b/cpu/efm32/periph/spi.c
@@ -20,6 +20,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "sched.h"
 #include "thread.h"
diff --git a/cpu/esp32/periph/can.c b/cpu/esp32/periph/can.c
index 103772896c..e3701589f5 100644
--- a/cpu/esp32/periph/can.c
+++ b/cpu/esp32/periph/can.c
@@ -15,6 +15,7 @@
  * @{
  */
 
+#include <assert.h>
 #include <errno.h>
 #include <string.h>
 
diff --git a/cpu/esp32/periph/gpio.c b/cpu/esp32/periph/gpio.c
index 8739718a66..d8941e055f 100644
--- a/cpu/esp32/periph/gpio.c
+++ b/cpu/esp32/periph/gpio.c
@@ -21,6 +21,7 @@
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
+#include <assert.h>
 #include <stdbool.h>
 
 #include "log.h"
diff --git a/cpu/esp8266/periph/pwm.c b/cpu/esp8266/periph/pwm.c
index c8ff89b6b6..f70bdcef05 100644
--- a/cpu/esp8266/periph/pwm.c
+++ b/cpu/esp8266/periph/pwm.c
@@ -18,6 +18,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
diff --git a/cpu/esp_common/freertos/queue.c b/cpu/esp_common/freertos/queue.c
index 53feb5b8cc..725c18a9ce 100644
--- a/cpu/esp_common/freertos/queue.c
+++ b/cpu/esp_common/freertos/queue.c
@@ -13,6 +13,7 @@
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
+#include <assert.h>
 #include <string.h>
 
 #include "esp_common.h"
diff --git a/cpu/esp_common/freertos/semphr.c b/cpu/esp_common/freertos/semphr.c
index 8769624b88..ad27be6388 100644
--- a/cpu/esp_common/freertos/semphr.c
+++ b/cpu/esp_common/freertos/semphr.c
@@ -13,6 +13,7 @@
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
+#include <assert.h>
 #include <string.h>
 
 #include "esp_common.h"
diff --git a/cpu/esp_common/freertos/task.c b/cpu/esp_common/freertos/task.c
index 78920c7d24..5ac936cd7b 100644
--- a/cpu/esp_common/freertos/task.c
+++ b/cpu/esp_common/freertos/task.c
@@ -13,6 +13,7 @@
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
+#include <assert.h>
 #include <string.h>
 
 #include "esp_common.h"
diff --git a/cpu/esp_common/freertos/timers.c b/cpu/esp_common/freertos/timers.c
index b134de96c1..d49b65df90 100644
--- a/cpu/esp_common/freertos/timers.c
+++ b/cpu/esp_common/freertos/timers.c
@@ -13,6 +13,7 @@
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
+#include <assert.h>
 #include <string.h>
 
 #include "esp_common.h"
diff --git a/cpu/esp_common/periph/flash.c b/cpu/esp_common/periph/flash.c
index 718df800aa..a34b25a90f 100644
--- a/cpu/esp_common/periph/flash.c
+++ b/cpu/esp_common/periph/flash.c
@@ -20,6 +20,7 @@
 
 #if MODULE_MTD
 
+#include <assert.h>
 #include <errno.h>
 #include <string.h>
 #include <stdlib.h>
diff --git a/cpu/esp_common/periph/spi.c b/cpu/esp_common/periph/spi.c
index b450999878..8c8fbafafa 100644
--- a/cpu/esp_common/periph/spi.c
+++ b/cpu/esp_common/periph/spi.c
@@ -19,13 +19,14 @@
  * @}
  */
 
+#include <assert.h>
+#include <string.h>
+
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 #include "esp_common.h"
 #include "log.h"
 
-#include <string.h>
-
 #include "cpu.h"
 #include "mutex.h"
 #include "periph/spi.h"
diff --git a/cpu/esp_common/periph/uart.c b/cpu/esp_common/periph/uart.c
index de9f2556a1..059b5cdd5a 100644
--- a/cpu/esp_common/periph/uart.c
+++ b/cpu/esp_common/periph/uart.c
@@ -19,6 +19,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
diff --git a/cpu/esp_common/syscalls.c b/cpu/esp_common/syscalls.c
index a4d44ec0b3..64d39cffb7 100644
--- a/cpu/esp_common/syscalls.c
+++ b/cpu/esp_common/syscalls.c
@@ -18,6 +18,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <string.h>
 #include <stdio_ext.h>
 #include <sys/unistd.h>
diff --git a/cpu/fe310/context_frame.c b/cpu/fe310/context_frame.c
index c3700ebaad..68c6d553e8 100644
--- a/cpu/fe310/context_frame.c
+++ b/cpu/fe310/context_frame.c
@@ -18,6 +18,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "context_frame.h"
 #include "thread.h"
 
diff --git a/cpu/fe310/periph/plic.c b/cpu/fe310/periph/plic.c
index a0c94e5344..e36f7fddf3 100644
--- a/cpu/fe310/periph/plic.c
+++ b/cpu/fe310/periph/plic.c
@@ -17,6 +17,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "vendor/encoding.h"
 #include "vendor/platform.h"
 #include "cpu.h"
diff --git a/cpu/kinetis/periph/uart.c b/cpu/kinetis/periph/uart.c
index f1c5edf378..d9ba1afb4f 100644
--- a/cpu/kinetis/periph/uart.c
+++ b/cpu/kinetis/periph/uart.c
@@ -24,6 +24,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "bit.h"
 #include "periph_conf.h"
diff --git a/cpu/lm4f120/periph/spi.c b/cpu/lm4f120/periph/spi.c
index f9e879f151..535a901773 100644
--- a/cpu/lm4f120/periph/spi.c
+++ b/cpu/lm4f120/periph/spi.c
@@ -17,6 +17,9 @@
  *
  * @}
  */
+
+#include <assert.h>
+
 #include "cpu.h"
 #include "mutex.h"
 #include "periph/gpio.h"
diff --git a/cpu/lpc1768/periph/gpio.c b/cpu/lpc1768/periph/gpio.c
index 3ac26d15c6..ba2775eb06 100644
--- a/cpu/lpc1768/periph/gpio.c
+++ b/cpu/lpc1768/periph/gpio.c
@@ -18,6 +18,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "periph/gpio.h"
 
diff --git a/cpu/lpc1768/periph/uart.c b/cpu/lpc1768/periph/uart.c
index 395c9c46ae..dc9df24b22 100644
--- a/cpu/lpc1768/periph/uart.c
+++ b/cpu/lpc1768/periph/uart.c
@@ -18,6 +18,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stdint.h>
 
 #include "cpu.h"
diff --git a/cpu/lpc23xx/mci/lpc23xx-mci.c b/cpu/lpc23xx/mci/lpc23xx-mci.c
index 967b8f0363..f7c74ed375 100644
--- a/cpu/lpc23xx/mci/lpc23xx-mci.c
+++ b/cpu/lpc23xx/mci/lpc23xx-mci.c
@@ -12,6 +12,7 @@
 /
 /---------------------------------------------------------------------------*/
 
+#include <assert.h>
 #include <string.h>
 #include "cpu.h"
 #include "VIC.h"
diff --git a/cpu/mips32r2_common/thread_arch.c b/cpu/mips32r2_common/thread_arch.c
index 56d434e99a..449ce1e203 100644
--- a/cpu/mips32r2_common/thread_arch.c
+++ b/cpu/mips32r2_common/thread_arch.c
@@ -6,6 +6,8 @@
  * General Public License v2.1. See the file LICENSE in the top level
  * directory for more details.
  */
+
+#include <assert.h>
 #include <mips/cpu.h>
 #include <mips/hal.h>
 #include <unistd.h>
diff --git a/cpu/mips_pic32_common/periph/timer.c b/cpu/mips_pic32_common/periph/timer.c
index 5b9bd40762..316f06f568 100644
--- a/cpu/mips_pic32_common/periph/timer.c
+++ b/cpu/mips_pic32_common/periph/timer.c
@@ -17,6 +17,7 @@
   * @}
   */
 
+#include <assert.h>
 #include <mips/cpu.h>
 #include <mips/m32c0.h>
 #include <mips/regdef.h>
diff --git a/cpu/msp430_common/periph/flashpage.c b/cpu/msp430_common/periph/flashpage.c
index 8a5b2fa5b6..4eaffe13bf 100644
--- a/cpu/msp430_common/periph/flashpage.c
+++ b/cpu/msp430_common/periph/flashpage.c
@@ -20,6 +20,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "irq.h"
 #include "periph/flashpage.h"
diff --git a/cpu/native/periph/pwm.c b/cpu/native/periph/pwm.c
index d0d936d723..a57f35754e 100644
--- a/cpu/native/periph/pwm.c
+++ b/cpu/native/periph/pwm.c
@@ -18,6 +18,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <errno.h>
 
 #include "periph/pwm.h"
diff --git a/cpu/nrf51/periph/pwm.c b/cpu/nrf51/periph/pwm.c
index d6ffc9f2d0..90741e8483 100644
--- a/cpu/nrf51/periph/pwm.c
+++ b/cpu/nrf51/periph/pwm.c
@@ -18,6 +18,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stdint.h>
 #include <string.h>
 #include <inttypes.h>
diff --git a/cpu/nrf52/periph/adc.c b/cpu/nrf52/periph/adc.c
index 4559c351f6..658c522141 100644
--- a/cpu/nrf52/periph/adc.c
+++ b/cpu/nrf52/periph/adc.c
@@ -20,6 +20,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "mutex.h"
 #include "periph/adc.h"
diff --git a/cpu/nrf52/periph/usbdev.c b/cpu/nrf52/periph/usbdev.c
index ec43b6c694..d7798b085b 100644
--- a/cpu/nrf52/periph/usbdev.c
+++ b/cpu/nrf52/periph/usbdev.c
@@ -22,6 +22,7 @@
 
 #define USB_H_USER_IS_RIOT_INTERNAL
 
+#include <assert.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <errno.h>
diff --git a/cpu/nrf52/radio/nrf802154/nrf802154.c b/cpu/nrf52/radio/nrf802154/nrf802154.c
index cbfeb9f69a..42455816ba 100644
--- a/cpu/nrf52/radio/nrf802154/nrf802154.c
+++ b/cpu/nrf52/radio/nrf802154/nrf802154.c
@@ -21,6 +21,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <string.h>
 #include <errno.h>
 
diff --git a/cpu/nrf52/radio/nrf802154/nrf802154_radio.c b/cpu/nrf52/radio/nrf802154/nrf802154_radio.c
index 2424e1b54e..60bb14b6b8 100644
--- a/cpu/nrf52/radio/nrf802154/nrf802154_radio.c
+++ b/cpu/nrf52/radio/nrf802154/nrf802154_radio.c
@@ -16,6 +16,8 @@
  * @author      José I. Alamos <jose.alamos@haw-hamburg.de>
  * @}
  */
+
+#include <assert.h>
 #include <string.h>
 #include <errno.h>
 
diff --git a/cpu/nrf52/spi_twi_irq.c b/cpu/nrf52/spi_twi_irq.c
index eb32412741..73fa24751d 100644
--- a/cpu/nrf52/spi_twi_irq.c
+++ b/cpu/nrf52/spi_twi_irq.c
@@ -20,6 +20,9 @@
  *
  * @}
  */
+
+#include <assert.h>
+
 #include "cpu.h"
 #include "periph_cpu.h"
 
diff --git a/cpu/nrf5x_common/periph/gpio.c b/cpu/nrf5x_common/periph/gpio.c
index 5aa017051e..dc91a1241e 100644
--- a/cpu/nrf5x_common/periph/gpio.c
+++ b/cpu/nrf5x_common/periph/gpio.c
@@ -28,6 +28,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "periph/gpio.h"
 #include "periph_cpu.h"
diff --git a/cpu/nrf5x_common/periph/uart.c b/cpu/nrf5x_common/periph/uart.c
index 878c49154b..9f798ccaff 100644
--- a/cpu/nrf5x_common/periph/uart.c
+++ b/cpu/nrf5x_common/periph/uart.c
@@ -28,6 +28,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stdint.h>
 #include <string.h>
 
diff --git a/cpu/nrf5x_common/periph/wdt.c b/cpu/nrf5x_common/periph/wdt.c
index aa34e505c7..834ad95a65 100644
--- a/cpu/nrf5x_common/periph/wdt.c
+++ b/cpu/nrf5x_common/periph/wdt.c
@@ -19,6 +19,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "timex.h"
 #include "periph/wdt.h"
diff --git a/cpu/nrf5x_common/radio/nrfmin/nrfmin_gnrc.c b/cpu/nrf5x_common/radio/nrfmin/nrfmin_gnrc.c
index 329df1816b..8390f2f8a4 100644
--- a/cpu/nrf5x_common/radio/nrfmin/nrfmin_gnrc.c
+++ b/cpu/nrf5x_common/radio/nrfmin/nrfmin_gnrc.c
@@ -18,6 +18,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "net/gnrc.h"
 #include "thread.h"
 #include "net/gnrc/netif.h"
diff --git a/cpu/sam0_common/periph/dac.c b/cpu/sam0_common/periph/dac.c
index 92e7aa9c35..b333acc601 100644
--- a/cpu/sam0_common/periph/dac.c
+++ b/cpu/sam0_common/periph/dac.c
@@ -18,6 +18,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "periph/dac.h"
 #include "periph/gpio.h"
diff --git a/cpu/sam0_common/periph/pwm.c b/cpu/sam0_common/periph/pwm.c
index dec6ebe691..eb707776cd 100644
--- a/cpu/sam0_common/periph/pwm.c
+++ b/cpu/sam0_common/periph/pwm.c
@@ -22,6 +22,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "board.h"
 #include "periph/gpio.h"
diff --git a/cpu/sam0_common/periph/timer.c b/cpu/sam0_common/periph/timer.c
index fe9dc8f60e..a156e2ccbd 100644
--- a/cpu/sam0_common/periph/timer.c
+++ b/cpu/sam0_common/periph/timer.c
@@ -20,6 +20,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
 
diff --git a/cpu/sam0_common/periph/usbdev.c b/cpu/sam0_common/periph/usbdev.c
index 68f04689ee..5c1d6c1a71 100644
--- a/cpu/sam0_common/periph/usbdev.c
+++ b/cpu/sam0_common/periph/usbdev.c
@@ -18,6 +18,7 @@
 
 #define USB_H_USER_IS_RIOT_INTERNAL
 
+#include <assert.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <errno.h>
diff --git a/cpu/sam3/periph/adc.c b/cpu/sam3/periph/adc.c
index 7cd58b652e..76ffc119bc 100644
--- a/cpu/sam3/periph/adc.c
+++ b/cpu/sam3/periph/adc.c
@@ -18,6 +18,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <stdio.h>
 
 
diff --git a/cpu/samd5x/cpu.c b/cpu/samd5x/cpu.c
index 1eefed9b4b..c14d6d90bb 100644
--- a/cpu/samd5x/cpu.c
+++ b/cpu/samd5x/cpu.c
@@ -17,6 +17,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "macros/units.h"
 #include "periph_conf.h"
diff --git a/cpu/saml21/cpu.c b/cpu/saml21/cpu.c
index 4f9a904689..bf407e9176 100644
--- a/cpu/saml21/cpu.c
+++ b/cpu/saml21/cpu.c
@@ -18,6 +18,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "periph/init.h"
 #include "periph_conf.h"
diff --git a/cpu/stm32/periph/can.c b/cpu/stm32/periph/can.c
index 41ca14a2ea..5b296088a7 100644
--- a/cpu/stm32/periph/can.c
+++ b/cpu/stm32/periph/can.c
@@ -17,6 +17,7 @@
  * @}
  */
 
+#include <assert.h>
 #include <string.h>
 #include <errno.h>
 #include <limits.h>
diff --git a/cpu/stm32/periph/eth.c b/cpu/stm32/periph/eth.c
index c5d0f8bdcd..2f8b1da536 100644
--- a/cpu/stm32/periph/eth.c
+++ b/cpu/stm32/periph/eth.c
@@ -19,6 +19,8 @@
  *
  * @}
  */
+
+#include <assert.h>
 #include <errno.h>
 #include <string.h>
 
diff --git a/cpu/stm32/periph/rtt_all.c b/cpu/stm32/periph/rtt_all.c
index 375d7bc562..1b62bdfd6f 100644
--- a/cpu/stm32/periph/rtt_all.c
+++ b/cpu/stm32/periph/rtt_all.c
@@ -19,6 +19,8 @@
  * @}
  */
 
+#include <assert.h>
+
 #include "cpu.h"
 #include "irq.h"
 #include "periph/rtt.h"
diff --git a/cpu/stm32/periph/usbdev.c b/cpu/stm32/periph/usbdev.c
index b3f5ecfb00..1e12802150 100644
--- a/cpu/stm32/periph/usbdev.c
+++ b/cpu/stm32/periph/usbdev.c
@@ -18,6 +18,7 @@
 
 #define USB_H_USER_IS_RIOT_INTERNAL
 
+#include <assert.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <errno.h>