From: Simon Tatham <anakin@pobox.com>
Date: Sun, 9 Mar 2014 23:14:24 +0000 (+0000)
Subject: Fix occasional 'min fragment 1.11022e-16' glitch.
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=13849e71956f8a3a2142cadd24c4f2006a328a04;p=matchsticks-search.git

Fix occasional 'min fragment 1.11022e-16' glitch.

Seems to happen in multicore mode when the first worker reports a
near-zero value of 'best', and then set_best reduces it to a negative
number when it applies the rounding fudge, leading to the max_frags
limits being set to negative things and all other workers' results
being thrown away in preconsider_ok().
---

diff --git a/main.c b/main.c
index a57bd72..8259c35 100644
--- a/main.c
+++ b/main.c
@@ -147,8 +147,10 @@ static void set_best(double new_best) {
    * subtract a fudge factor from our target.
    */
   double near_best = best * 0.98 - 0.02;
-  n_max_frags = ceil(n / near_best) - 1;
-  m_max_frags = ceil(m / near_best) - 1;
+  if (near_best > 0) {
+    n_max_frags = ceil(n / near_best) - 1;
+    m_max_frags = ceil(m / near_best) - 1;
+  }
 }
 
 /*----- multicore support -----*/