From 35e0a53d62f3098b627f1d8d48e99d9b707a96dd Mon Sep 17 00:00:00 2001
From: Hrvoje Jasak <h.jasak@wikki.co.uk>
Date: Thu, 8 Nov 2018 19:32:34 +0000
Subject: [PATCH] Bugfix: Reading of zone meshes in parallel; load balancing

---
 .../meshes/polyMesh/zones/ZoneMesh/ZoneMesh.C | 30 +++++++++++--------
 1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/src/foam/meshes/polyMesh/zones/ZoneMesh/ZoneMesh.C b/src/foam/meshes/polyMesh/zones/ZoneMesh/ZoneMesh.C
index 0323fdaed..3172453da 100644
--- a/src/foam/meshes/polyMesh/zones/ZoneMesh/ZoneMesh.C
+++ b/src/foam/meshes/polyMesh/zones/ZoneMesh/ZoneMesh.C
@@ -164,24 +164,28 @@ ZoneMesh<ZoneType, MeshType>::ZoneMesh
     mesh_(mesh),
     zoneMapPtr_(NULL)
 {
-    PtrList<ZoneType>& zones = *this;
-
     PtrList<entry> zoneEntries(is);
-    zones.setSize(zoneEntries.size());
 
-    forAll(zones, zoneI)
+    if (!zoneEntries.empty())
     {
-        zones.set
-        (
-            zoneI,
-            ZoneType::New
+        PtrList<ZoneType>& zones = *this;
+
+        zones.setSize(zoneEntries.size());
+
+        forAll(zones, zoneI)
+        {
+            zones.set
             (
-                zoneEntries[zoneI].keyword(),
-                zoneEntries[zoneI].dict(),
                 zoneI,
-                *this
-            )
-        );
+                ZoneType::New
+                (
+                    zoneEntries[zoneI].keyword(),
+                    zoneEntries[zoneI].dict(),
+                    zoneI,
+                    *this
+                )
+            );
+        }
     }
 }