/src/lib/util/huffman.c

529  //-------------------------------------------------
530  //  tree_node_compare - compare two tree nodes
531  //  by weight
532  //-------------------------------------------------
533  
534  int CLIB_DECL huffman_context_base::tree_node_compare(const void *item1, const void *item2)
535  {
536      const node_t *node1 = *(const node_t **)item1;
537      const node_t *node2 = *(const node_t **)item2;
538      return node2->m_weight - node1->m_weight;
539  }

...

565      // sort the list by weight, largest weight first
566      qsort(list, listitems, sizeof(list[0]), tree_node_compare); 

Quote:

---

Warning: If two objects compare as equal, their order after sorting is unpredictable. That is to say, the sorting is not stable. This can make a difference when the comparison considers only part of the elements. Two elements with the same sort key may differ in other respects.

If you want the effect of a stable sort, you can get this result by writing the comparison function so that, lacking other reason distinguish between two elements, it compares them by their addresses. Note that doing this may make the sorting algorithm less efficient, so do it only if necessary.

Quote:

---

glibc normally uses merge sort for implementing qsort(), hence it's
usually stable. It only uses a real quicksort when using merge sort would
require too much memory (defined as more than one quarter of physical
RAM). I.e. in practice it's stable.

Index: src/lib/util/chd.c
===================================================================
--- src/lib/util/chd.c	(revision 15463)
+++ src/lib/util/chd.c	(working copy)
@@ -1788,6 +1788,7 @@
 		compressed[12] = lengthbits;
 		compressed[13] = selfbits;
 		compressed[14] = parentbits;
+		compressed[15] = 0;
 
 		// write the result
 		m_mapoffset = file_append(compressed, complen + 16);

Index: src/lib/util/cdrom.c
===================================================================
--- src/lib/util/cdrom.c	(revision 15463)
+++ src/lib/util/cdrom.c	(working copy)
@@ -734,6 +734,7 @@
 		{
 			/* parse the metadata */
 			type[0] = subtype[0] = 0;
+			pgtype[0] = pgsub[0] = 0;
 			if (sscanf(metadata, CDROM_TRACK_METADATA_FORMAT, &tracknum, type, subtype, &frames) != 4)
 				return CHDERR_INVALID_DATA;
 			if (tracknum == 0 || tracknum > CD_MAX_TRACKS)