Skip non-driven nodes during DFS.

src/base/wlc/wlcNdr.c

@@ -469,6 +469,7 @@ Wlc_Ntk_t * Wlc_NtkFromNdr( void * pData )
         assert( !fFound && i == NameId );
     }
     //Ndr_NtkPrintNodes( pNtk );
+    //Wlc_WriteVer( pNtk, "temp_ndr.v", 0, 0 );
     // derive topological order
     pNtk = Wlc_NtkDupDfs( pTemp = pNtk, 0, 1 );
     Wlc_NtkFree( pTemp );

src/base/wlc/wlcNtk.c

@@ -866,6 +866,8 @@ void Wlc_NtkDupDfs_rec( Wlc_Ntk_t * pNew, Wlc_Ntk_t * p, int iObj, Vec_Int_t * v
 {
     Wlc_Obj_t * pObj;
     int i, iFanin;
+    if ( iObj == 0 )
+        return;
     if ( Wlc_ObjCopy(p, iObj) )
         return;
     //printf( "Visiting node %d\n", iObj );