int
default_fast_tracepoint_valid_at (struct gdbarch *gdbarch, CORE_ADDR addr,
- char **msg)
+ std::string *msg)
{
/* We don't know if maybe the target has some way to do fast
tracepoints that doesn't need gdbarch, so always say yes. */
if (msg)
- *msg = NULL;
+ msg->clear ();
return 1;
}