libc {
  GLIBC_2.0 {
    # variables used for detecting cthreads
    _cthread_exit_routine; _cthread_init_routine;

    # cthreads functions with stubs in libc
    cthread_keycreate; cthread_getspecific; cthread_setspecific;
    __libc_getspecific;

    # functions with a weak definition in the dynamic linker
    __getcwd; __mmap;
  }
}