diff --git a/ports/esp32/machine_pin.c b/ports/esp32/machine_pin.c
index 89ff9d8b77..2a26d6bfb0 100644
--- a/ports/esp32/machine_pin.c
+++ b/ports/esp32/machine_pin.c
@@ -38,8 +38,6 @@
 #include "machine_rtc.h"
 #include "modesp32.h"
 
-extern machine_rtc_config_t machine_rtc_config;
-
 typedef struct _machine_pin_obj_t {
     mp_obj_base_t base;
     gpio_num_t id;
diff --git a/ports/esp32/machine_rtc.h b/ports/esp32/machine_rtc.h
index c2016ca792..e34deb9be6 100644
--- a/ports/esp32/machine_rtc.h
+++ b/ports/esp32/machine_rtc.h
@@ -39,4 +39,6 @@ typedef struct {
     bool ext1_level : 1;
 } machine_rtc_config_t;
 
+extern machine_rtc_config_t machine_rtc_config;
+
 #endif
diff --git a/ports/esp32/modesp32.c b/ports/esp32/modesp32.c
index db78248f82..6d18e0add1 100644
--- a/ports/esp32/modesp32.c
+++ b/ports/esp32/modesp32.c
@@ -40,8 +40,6 @@
 #include "machine_rtc.h"
 #include "modesp32.h"
 
-extern machine_rtc_config_t machine_rtc_config;
-
 STATIC mp_obj_t esp32_wake_on_touch(const mp_obj_t wake) {
 
     if (machine_rtc_config.ext0_pin != -1) {
diff --git a/ports/esp32/modmachine.c b/ports/esp32/modmachine.c
index 72211a2c53..2d59e137ef 100644
--- a/ports/esp32/modmachine.c
+++ b/ports/esp32/modmachine.c
@@ -49,8 +49,6 @@
 
 #if MICROPY_PY_MACHINE
 
-extern machine_rtc_config_t machine_rtc_config;
-
 typedef enum {
     MP_PWRON_RESET = 1,
     MP_HARD_RESET,