diff --git a/[refs] b/[refs]
index 4f0b8c5bda69..0dd5ec9b81e5 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 56f3bae70638b33477a6015fd362ccfe354fd3ee
+refs/heads/master: 19f4740255668ca297dcf9f02d80eb9bc87a1d66
diff --git a/trunk/tools/perf/builtin-stat.c b/trunk/tools/perf/builtin-stat.c
index a43c68051078..af0d65b41416 100644
--- a/trunk/tools/perf/builtin-stat.c
+++ b/trunk/tools/perf/builtin-stat.c
@@ -254,8 +254,13 @@ static double avg_stats(struct stats *stats)
  */
 static double stddev_stats(struct stats *stats)
 {
-	double variance = stats->M2 / (stats->n - 1);
-	double variance_mean = variance / stats->n;
+	double variance, variance_mean;
+
+	if (!stats->n)
+		return 0.0;
+
+	variance = stats->M2 / (stats->n - 1);
+	variance_mean = variance / stats->n;
 
 	return sqrt(variance_mean);
 }