From: Augustin Degomme <augustin.degomme@unibas.ch>
Date: Sat, 2 Sep 2017 15:28:39 +0000 (+0200)
Subject: avoid potential division by 0... But not sure 0 is right as an answer here
X-Git-Tag: v3_17~171
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/b98b530ed10d60d9c350bf4919896a0c50b649f3

avoid potential division by 0... But not sure 0 is right as an answer here
---

diff --git a/src/smpi/colls/coll_tuned_topo.cpp b/src/smpi/colls/coll_tuned_topo.cpp
index aa797a9884..db88a997bb 100644
--- a/src/smpi/colls/coll_tuned_topo.cpp
+++ b/src/smpi/colls/coll_tuned_topo.cpp
@@ -52,7 +52,10 @@ static int calculate_num_nodes_up_to_level( int fanout, int level )
 {
     /* just use geometric progression formula for sum:
        a^0+a^1+...a^(n-1) = (a^n-1)/(a-1) */
-    return ((pown(fanout,level) - 1)/(fanout - 1));
+  if(fanout > 1)  
+   return ((pown(fanout,level) - 1)/(fanout - 1));
+  else
+   return 0; // is this right ?
 }
 
 /*