Hi, I got gcc42,gcc43,and gcc34,seperately in /usr/local/gcc42 , /usr/local/gcc43 , /usr/local/gcc34 directory on my server. I use gcc43 to compile PARSEC benchmark,but i got the following error: /usr/local/libstdc++.so: undefined reference to '_Unwind_GetIPInfo@xxxxxxxxx' /usr/local/libstdc++.so: undefined reference to ... ... I have link /usr/local/lib64/libstdc++.so TO /usr/local/gcc43/libstdc++.so.6.0.10 , and I don't know what's going wrong? Could u guys help me fix this? Thanks -- LuLu He Cluster and Grid Computing Lab (CGCL) Services Computing Technology and System Lab (SCTS) School of Computer Science and Technology (CS) Huazhong University of Science and Technology (HUST) Wuhan, 430074, China