Fix Python warnings.

prrt/proto/socket.c

@@ -273,7 +273,6 @@ bool PrrtSocket_closing(PrrtSocket *s) {
 }
 
 int32_t PrrtSocket_receive_asap(PrrtSocket *s, void *buf_ptr) {
-    prrtPacketLength_t len = 0;
     check(s->isSender == false, "Cannot receive on sender socket.")
 
     PrrtPacket *packet;
@@ -319,8 +318,6 @@ int32_t PrrtSocket_recv(PrrtSocket *s, void *buf_ptr) {
 }
 
 int32_t PrrtSocket_receive_ordered(PrrtSocket *s, void *buf_ptr, prrtTimedelta_t time_window_us) {
-    prrtPacketLength_t len = 0;
-
     check(s->isSender == false, "Cannot receive on sender socket.")
 
     prrtTimestamp_t now = PrrtClock_get_current_time_us();

prrt/util/mpsc_queue.c

@@ -3,7 +3,7 @@
 #include <stdio.h>
 #include <assert.h>
 
-MPSCQueue* MPSCQueue_create()
+MPSCQueue* MPSCQueue_create(void)
 {
     MPSCQueue* self = calloc(1, sizeof(MPSCQueue));
     mpscq_node_t* stub = calloc(1, sizeof(mpscq_node_t));

prrt/util/mpsc_queue.h

@@ -22,7 +22,7 @@ typedef struct mpscq_t
     volatile int size;
 } MPSCQueue;
 
-MPSCQueue* MPSCQueue_create();
+MPSCQueue* MPSCQueue_create(void);
 void MPSCQueue_push(MPSCQueue *self, void *value);
 void* MPSCQueue_pop(MPSCQueue* self);
 void MPSCQueue_destroy(MPSCQueue *self);