Fixing support for CYGWIN

src/VCluster/VCluster.cpp

 #define PRINT_STACKTRACE
 
 #include "VCluster.hpp"
+#ifndef __CYGWIN__
 #include <execinfo.h>
+#endif
 
 #include "util/print_stack.hpp"
 

src/VCluster/VCluster_base.hpp

@@ -242,7 +242,7 @@ public:
 		MPI_Comm_rank(MPI_COMM_WORLD, &m_rank);
 
 #ifdef SE_CLASS2
-			process_v_cl = rank;
+			process_v_cl = m_rank;
 #endif
 
 		// create and fill map scatter with one