diff --git a/armsrc/optimized_cipher.c b/armsrc/optimized_cipher.c
index 0f762a8d6..24bb8d7ee 100644
--- a/armsrc/optimized_cipher.c
+++ b/armsrc/optimized_cipher.c
@@ -245,7 +245,6 @@ void opt_doReaderMAC(uint8_t *cc_nr_p, uint8_t *div_key_p, uint8_t mac[4]) {
     uint8_t dest [] = {0, 0, 0, 0, 0, 0, 0, 0};
     opt_MAC(div_key_p, cc_nr_p, dest);
     memcpy(mac, dest, 4);
-    return;
 }
 
 void opt_doTagMAC(uint8_t *cc_p, const uint8_t *div_key_p, uint8_t mac[4]) {
@@ -257,7 +256,6 @@ void opt_doTagMAC(uint8_t *cc_p, const uint8_t *div_key_p, uint8_t mac[4]) {
     };
     opt_suc(div_key_p, &_init, cc_p, 12, true);
     opt_output(div_key_p, &_init, mac);
-    return;
 }
 
 /**
@@ -291,5 +289,4 @@ State opt_doTagMAC_1(uint8_t *cc_p, const uint8_t *div_key_p) {
 void opt_doTagMAC_2(State _init,  uint8_t *nr, uint8_t mac[4], const uint8_t *div_key_p) {
     opt_suc(div_key_p, &_init, nr, 4, true);
     opt_output(div_key_p, &_init, mac);
-    return;
 }