I am currently using a shared library (whose source i don't have access to) that is linked against libstdc++.so.5. For reasons that i am not into explaining we must compile and link against this library on RedHat Linux EL 5 that comes with a gcc > 4 and defaults its c++ runtime to version 6 ( libstdc++.so.6). This results in memory leaks because memory allocated on one runtime cannot be freed on the other. Is there a way to force linking on libstdc++.so.5? From an internet search it seems to me that the only way is to build gcc 3.3 on my development box. If this is the answer then i would like to know how can the built gcc version be able to use libstdc++.so.5 since the default runtime is libstdc++.so.6. Thanks in advance, Luca Regini