don't throw an exception if attributes are not defined -- just issue an error

Geo/Makefile

-# $Id: Makefile,v 1.120 2006-11-29 20:40:47 geuzaine Exp $
+# $Id: Makefile,v 1.121 2006-12-03 03:19:55 geuzaine Exp $
 #
 # Copyright (C) 1997-2007 C. Geuzaine, J.-F. Remacle
 #
@@ -124,7 +124,7 @@ gmshRegion.o: gmshRegion.cpp GModel.h GVertex.h GEntity.h Range.h \
   MFace.h ../Numeric/Numeric.h ../Common/Context.h ../DataStr/List.h \
   ExtrudeParams.h GFace.h GEdgeLoop.h Pair.h GRegion.h \
   ../Common/SmoothNormals.h gmshFace.h Geo.h ../DataStr/Tree.h \
-  ../DataStr/avl.h gmshVertex.h gmshRegion.h
+  ../DataStr/avl.h gmshVertex.h gmshRegion.h ../Common/Message.h
 OCCVertex.o: OCCVertex.cpp GModel.h GVertex.h GEntity.h Range.h SPoint3.h \
   SBoundingBox3d.h ../Common/GmshDefines.h MVertex.h GPoint.h SPoint2.h \
   GEdge.h SVector3.h MElement.h MEdge.h ../Common/Hash.h MFace.h \

Geo/gmshFace.cpp

-// $Id: gmshFace.cpp,v 1.28 2006-12-03 01:36:20 geuzaine Exp $
+// $Id: gmshFace.cpp,v 1.29 2006-12-03 03:19:55 geuzaine Exp $
 //
 // Copyright (C) 1997-2007 C. Geuzaine, J.-F. Remacle
 //
@@ -76,8 +76,10 @@ gmshFace::gmshFace(GModel *m, Surface *face)
       Vertex *corn;
       List_Read(s->TrsfPoints, i, &corn);
       GVertex *gv = m->vertexByTag(corn->Num);
-      if(!gv) throw;
+      if(gv)
 	meshAttributes.corners.push_back(gv);
+      else
+	Msg(GERROR, "Unknown vertex %d in transfinite attributes", corn->Num);
     }
   }
 }

Geo/gmshRegion.cpp

-// $Id: gmshRegion.cpp,v 1.11 2006-12-02 19:29:36 geuzaine Exp $
+// $Id: gmshRegion.cpp,v 1.12 2006-12-03 03:19:55 geuzaine Exp $
 //
 // Copyright (C) 1997-2007 C. Geuzaine, J.-F. Remacle
 //
@@ -23,6 +23,7 @@
 #include "gmshFace.h"
 #include "gmshRegion.h"
 #include "Geo.h"
+#include "Message.h"
 
 extern Mesh *THEM;
 
@@ -47,8 +48,10 @@ gmshRegion::gmshRegion(GModel *m, ::Volume * volume)
       Vertex *corn;
       List_Read(volume->TrsfPoints, i, &corn);
       GVertex *gv = m->vertexByTag(corn->Num);
-      if(!gv) throw;
+      if(gv)
 	meshAttributes.corners.push_back(gv);
+      else
+	Msg(GERROR, "Unknown vertex %d in transfinite attributes", corn->Num);
     }
   }
 }