Index: utils.c
===================================================================
--- utils.c	(revision 353316)
+++ utils.c	(working copy)
@@ -736,10 +736,16 @@
 		return;
 	}
 
-	if ((symbols = backtrace_symbols(bt->addresses, bt->num_frames))) {
+	/* There is no locking so the backtrace buffer can be filling as we
+	   are working.  Make sure we use the same frame count for everything
+	   as outputting more frames than we have formatted can produce a 
+	   crash.  A reduction should just produce garbled addresses. */ 
+	int num_frames_snapshot = bt->num_frames;
+
+	if ((symbols = backtrace_symbols(bt->addresses, num_frames_snapshot))) {
 		int frame_iterator;
 		
-		for (frame_iterator = 0; frame_iterator < bt->num_frames; ++frame_iterator) {
+		for (frame_iterator = 0; frame_iterator < num_frames_snapshot; ++frame_iterator) {
 			ast_str_append(str, 0, "\t%s\n", symbols[frame_iterator]);
 		}