diff --git a/components/esp_adc_cal/include/esp_adc_cal.h b/components/esp_adc_cal/include/esp_adc_cal.h
index b1798847bd..b5a869e28a 100644
--- a/components/esp_adc_cal/include/esp_adc_cal.h
+++ b/components/esp_adc_cal/include/esp_adc_cal.h
@@ -15,14 +15,14 @@
 #ifndef __ESP_ADC_CAL_H__
 #define __ESP_ADC_CAL_H__
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 #include <stdint.h>
 #include "esp_err.h"
 #include "driver/adc.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * @brief Type of calibration value used in characterization
  */