===================================================================
@@ -30,12 +30,14 @@
unsigned int n_bytes = sizeof (struct sparseset_def)
+ ((n_elms - 1) * 2 * sizeof (SPARSESET_ELT_TYPE));
- /* We use xcalloc rather than xmalloc to silence some valgrind uninitialized
+ sparseset set = XNEWVAR(struct sparseset_def, n_bytes);
+
+ /* Mark the sparseset as defined to silence some valgrind uninitialized
read errors when accessing set->sparse[n] when "n" is not, and never has
been, in the set. These uninitialized reads are expected, by design and
- harmless. If this turns into a performance problem due to some future
- additional users of sparseset, we can revisit this decision. */
- sparseset set = (sparseset) xcalloc (1, n_bytes);
+ harmless. */
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_DEFINED (set, n_bytes));
+
set->dense = &(set->elms[0]);
set->sparse = &(set->elms[n_elms]);
set->size = n_elms;