__gnu_cxx::__mt_alloc(3cxx) on Linux
The text e0a8f1a7ecdb, as Debian 6.0 (Squeeze) shipped it.
This is a fixed size (power of 2) allocator which - when compiled with thread support - will maintain one freelist per size per thread plus a 'global' one. Steps are taken to limit the per thread freelist sizes (by returning excess back to the 'global' list). Further details: http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt12ch32.html.