From f8d609fee54e03d5f2667c1fcdd5b248f18b39f4 Mon Sep 17 00:00:00 2001
From: Miroslav Lichvar <mlichvar@redhat.com>
Date: Wed, 19 Jun 2013 10:22:49 +0200
Subject: [PATCH] Add minimum skew limit to sourcestats

---
 sourcestats.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/sourcestats.c b/sourcestats.c
index 616b326..8df7740 100644
--- a/sourcestats.c
+++ b/sourcestats.c
@@ -51,6 +51,9 @@ int min_samples;
    2000ppm, which would be pretty bad */
 #define WORST_CASE_FREQ_BOUND (2000.0/1.0e6)
 
+/* The minimum allowed skew */
+#define MIN_SKEW 1.0e-12
+
 /* ================================================== */
 
 static LOG_FileID logfileid;
@@ -453,6 +456,9 @@ SST_DoNewRegression(SST_Stats inst)
     inst->variance = est_var;
     inst->nruns = nruns;
 
+    if (inst->skew < MIN_SKEW)
+      inst->skew = MIN_SKEW;
+
     stress = fabs(old_freq - inst->estimated_frequency) / old_skew;
 
     if (best_start > 0) {