From Kovarththanan Rajaratnam: dfilter: Fix for bug #3490:

"Purify reports an uninitialized memory read in dfw_append_const() when
accessing the 'next_const_id' member. This seems to be caused by dfwork_new()
which doesn't properly initialize the member."

svn path=/trunk/; revision=28486

epan/dfilter/dfilter.c

@@ -179,6 +179,7 @@ dfwork_new(void)
 	dfw->loaded_fields = NULL;
 	dfw->interesting_fields = NULL;
 	dfw->next_insn_id = 0;
+	dfw->next_const_id = 0;
 	dfw->next_register = 0;
 	dfw->first_constant = -1;