diff -u -r a/cores/arduino/main.cpp b/cores/arduino/main.cpp
--- a/cores/arduino/main.cpp	2019-05-16 15:52:01.000000000 +0300
+++ b/cores/arduino/main.cpp	2020-11-17 18:56:01.243474508 +0300
@@ -30,6 +30,7 @@
 void setupUSB() __attribute__((weak));
 void setupUSB() { }
 
+/*
 int main(void)
 {
 	init();
@@ -49,4 +50,5 @@
         
 	return 0;
 }
+*/