Index: libmpdemux/demux_mkv.c
===================================================================
--- libmpdemux/demux_mkv.c	(revision 29731)
+++ libmpdemux/demux_mkv.c	(working copy)
@@ -203,16 +203,25 @@
 extern int dvdsub_id;
 
 /**
- * \brief ensures there is space for at least one additional element
+ * \brief ensures there is space for at least one additional uint64_t
  * \param array array to grow
  * \param nelem current number of elements in array
- * \param elsize size of one array element
  */
-static void grow_array(void **array, int nelem, size_t elsize) {
+static void grow_array_uint64(uint64_t **array, int nelem) {
   if (!(nelem & 31))
-    *array = realloc(*array, (nelem + 32) * elsize);
+    *array = realloc(*array, (nelem + 32) * sizeof(uint64_t));
 }
 
+/**
+ * \brief ensures there is space for at least one additional mkv_index_t
+ * \param array array to grow
+ * \param nelem current number of elements in array
+ */
+static void grow_array_mkv_index(mkv_index_t **array, int nelem) {
+  if (!(nelem & 31))
+    *array = realloc(*array, (nelem + 32) * sizeof(mkv_index_t));
+}
+
 static mkv_track_t *
 demux_mkv_find_track_by_num (mkv_demuxer_t *d, int n, int type)
 {
@@ -235,8 +244,7 @@
     if (mkv_d->cluster_positions[i] == position)
       return;
 
-  grow_array((void **)&mkv_d->cluster_positions, mkv_d->num_cluster_pos,
-             sizeof(uint64_t));
+  grow_array_uint64(&mkv_d->cluster_positions, mkv_d->num_cluster_pos);
   mkv_d->cluster_positions[mkv_d->num_cluster_pos++] = position;
 }
 
@@ -1079,7 +1087,7 @@
       if (time != EBML_UINT_INVALID && track != EBML_UINT_INVALID
           && pos != EBML_UINT_INVALID)
         {
-          grow_array((void **)&mkv_d->indexes, mkv_d->num_indexes, sizeof(mkv_index_t));
+          grow_array_mkv_index(&mkv_d->indexes, mkv_d->num_indexes);
           mkv_d->indexes[mkv_d->num_indexes].tnum = track;
           mkv_d->indexes[mkv_d->num_indexes].timecode = time;
           mkv_d->indexes[mkv_d->num_indexes].filepos =mkv_d->segment_start+pos;