diff --git a/sys/chardev_thread.c b/sys/chardev_thread.c
index a4be247d4f018bf72cbd370233f89d6ebfaa9a8b..cd3180c713a8812e468ae8ea906b7c32cf6fec00 100644
--- a/sys/chardev_thread.c
+++ b/sys/chardev_thread.c
@@ -107,7 +107,7 @@ void chardev_loop(ringbuffer_t *rb)
             DEBUG("Data is available\n");
             unsigned state = disableIRQ();
             int nbytes = min(r->nbytes, rb->avail);
-            DEBUG("uart0_thread [%i]: sending %i bytes received from %" PRIkernel_pid " to pid %" PRIkernel_pid "\n", pid, nbytes, m.sender_pid, reader_pid);
+            DEBUG("uart0_thread [%i]: sending %i bytes received from %" PRIkernel_pid " to pid %" PRIkernel_pid "\n", thread_getpid(), nbytes, m.sender_pid, reader_pid);
             ringbuffer_get(rb, r->buffer, nbytes);
             r->nbytes = nbytes;
 
diff --git a/sys/include/timex.h b/sys/include/timex.h
index 846cbe9deb8ac6eda257db83668f211f5ad093be..a860331cfa95d0aec71561e139c2d19179a7aecc 100644
--- a/sys/include/timex.h
+++ b/sys/include/timex.h
@@ -123,7 +123,7 @@ static inline void timex_normalize(timex_t *time)
  * @return true for a normalized timex_t
  * @return false otherwise
  */
-static inline int timex_isnormalized(timex_t *time)
+static inline int timex_isnormalized(const timex_t *time)
 {
     return (time->microseconds < SEC_IN_USEC);
 }
diff --git a/sys/timex/timex.c b/sys/timex/timex.c
index 9ba47ed92ee267984032614e9c217a12ac8c5be2..a2aa49fc40d17171677637777ea1de1b10b756b2 100644
--- a/sys/timex/timex.c
+++ b/sys/timex/timex.c
@@ -29,7 +29,7 @@
 timex_t timex_add(const timex_t a, const timex_t b)
 {
 #if ENABLE_DEBUG
-    if (!timex_isnormalized(a) || !timex_isnormalized(b)) {
+    if (!timex_isnormalized(&a) || !timex_isnormalized(&b)) {
         puts("timex_add on denormalized value");
     }
 #endif
@@ -53,7 +53,7 @@ timex_t timex_set(uint32_t seconds, uint32_t microseconds)
     result.microseconds = microseconds;
 
 #if ENABLE_DEBUG
-    if (!timex_isnormalized(result)) {
+    if (!timex_isnormalized(&result)) {
         puts("timex_set on denormalized value");
     }
 #endif
@@ -64,7 +64,7 @@ timex_t timex_set(uint32_t seconds, uint32_t microseconds)
 timex_t timex_sub(const timex_t a, const timex_t b)
 {
 #if ENABLE_DEBUG
-    if (!timex_isnormalized(a) || !timex_isnormalized(b)) {
+    if (!timex_isnormalized(&a) || !timex_isnormalized(&b)) {
         puts("timex_sub on denormalized value");
     }
 #endif
@@ -86,7 +86,7 @@ timex_t timex_sub(const timex_t a, const timex_t b)
 int timex_cmp(const timex_t a, const timex_t b)
 {
 #if ENABLE_DEBUG
-    if (!timex_isnormalized(a) || !timex_isnormalized(b)) {
+    if (!timex_isnormalized(&a) || !timex_isnormalized(&b)) {
         puts("timex_cmp on denormalized value");
     }
 #endif
diff --git a/sys/vtimer/vtimer.c b/sys/vtimer/vtimer.c
index 2cf0f638308dd8cfb186726e6b8ca03b382c9157..4662ac8821555f601646f17d2c34f97ef9918589 100644
--- a/sys/vtimer/vtimer.c
+++ b/sys/vtimer/vtimer.c
@@ -423,11 +423,11 @@ int vtimer_msg_receive_timeout(msg_t *m, timex_t timeout) {
 
 #if ENABLE_DEBUG
 
-void vtimer_print_short_queue(){
+void vtimer_print_short_queue(void){
     priority_queue_print(&shortterm_priority_queue_root);
 }
 
-void vtimer_print_long_queue(){
+void vtimer_print_long_queue(void){
     priority_queue_print(&longterm_priority_queue_root);
 }