diff --git a/demod_afsk.c b/demod_afsk.c
index c5d248a..b769e21 100644
--- a/demod_afsk.c
+++ b/demod_afsk.c
@@ -720,7 +720,7 @@ static void emit_macro (char *name, int size, float *coeff)
 	dw_printf ("\n");
 }
 
-int main ()
+int main (void)
 {
 	//int n;
 	char fff_profile;