From fa7612374ad996fac6340e7478d47eb2db8bbc11 Mon Sep 17 00:00:00 2001
From: vsr <vsr@opencascade.com>
Date: Fri, 22 Apr 2011 14:44:29 +0000
Subject: [PATCH] Fix problem in DifferenceList() function: when group becomes
 empty, an invalid compound is created by error.

---
 src/GEOMImpl/GEOMImpl_IGroupOperations.cxx | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/src/GEOMImpl/GEOMImpl_IGroupOperations.cxx b/src/GEOMImpl/GEOMImpl_IGroupOperations.cxx
index cf81ed23c..86ed5fbe7 100644
--- a/src/GEOMImpl/GEOMImpl_IGroupOperations.cxx
+++ b/src/GEOMImpl/GEOMImpl_IGroupOperations.cxx
@@ -485,14 +485,20 @@ void GEOMImpl_IGroupOperations::DifferenceList (Handle(GEOM_Object) theGroup,
 
   if (mapIDsToRemove.Extent() > 0) {
     Standard_Integer k = 1, aRemLength = mapIDsToRemove.Extent();
-    Handle(TColStd_HArray1OfInteger) aNewSeq = new TColStd_HArray1OfInteger(1, aLength - aRemLength);
-
-    for (j = 1; j <= aLength; j++) {
-      if (!mapIDsToRemove.Contains(aSeq->Value(j))) {
-        aNewSeq->SetValue(k, aSeq->Value(j));
-        k++;
+    Handle(TColStd_HArray1OfInteger) aNewSeq;
+    if ( aLength - aRemLength > 0 ) {
+      aNewSeq = new TColStd_HArray1OfInteger(1, aLength - aRemLength);
+      for (j = 1; j <= aLength; j++) {
+	if (!mapIDsToRemove.Contains(aSeq->Value(j))) {
+	  aNewSeq->SetValue(k, aSeq->Value(j));
+	  k++;
+	}
       }
     }
+    else {
+      aNewSeq = new TColStd_HArray1OfInteger(1,1);
+      aNewSeq->SetValue(1, -1);
+    }
 
     aSSI.SetIndices(aNewSeq);
 
-- 
2.39.2