core: added assert to cib_init()

core/include/cib.h

@@ -51,6 +51,9 @@ typedef struct {
  */
 static inline void cib_init(cib_t *__restrict cib, unsigned int size)
 {
+    /* check if size is a power of 2 by comparing it to its complement */
+    assert(!(size & (size - 1)));
+
     cib_t c = CIB_INIT(size);
     *cib = c;
 }