diff --git a/esp8266/mpconfigport.h b/esp8266/mpconfigport.h
index 1a9e54ee05..269882d0dc 100644
--- a/esp8266/mpconfigport.h
+++ b/esp8266/mpconfigport.h
@@ -24,7 +24,7 @@
 #define MICROPY_ENABLE_SOURCE_LINE  (1)
 #define MICROPY_MODULE_WEAK_LINKS   (1)
 #define MICROPY_CAN_OVERRIDE_BUILTINS (1)
-#define MICROPY_USE_INTERNAL_ERRNO  (0)
+#define MICROPY_USE_INTERNAL_ERRNO  (1)
 #define MICROPY_PY_BUILTINS_COMPLEX (0)
 #define MICROPY_PY_BUILTINS_STR_UNICODE (1)
 #define MICROPY_PY_BUILTINS_BYTEARRAY (1)