Hi -- I've installed GCC 4.6.0 on my MacBook Pro (running Snow Leopard), and have compiled a simple hello world c++ program with it. Unfortunately, when I try to do something more complex using the Boost Serialization library, the code compiles and links, but I get the following error when I run it: run_features(2872) malloc: *** error for object 0x100502060: pointer being freed was not allocated *** set a breakpoint in malloc_error_break to debug This occurs when I try to create an xml archive with a stringstream. The code compiles fine under GCC 4.2, it's only with 4.6.0 that I get this error. I reinstalled Boost with GCC 4.6.0 (by fixing symlinks to cc, gcc, and g++ & using homebrew) to be sure that it wasn't something there. For reference, the error is caused by line 24 of this file: https://gist.github.com/923262 I'm just learning C++ & GCC development, so I'm a bit stumped, now, as to what I can do next -- could anyone advise me on how I might resolve this, or where I might look for information to help me? Thanks very much, Doug.