}
int
-gdbarch_fast_tracepoint_valid_at (struct gdbarch *gdbarch, CORE_ADDR addr, char **msg)
+gdbarch_fast_tracepoint_valid_at (struct gdbarch *gdbarch, CORE_ADDR addr, std::string *msg)
{
gdb_assert (gdbarch != NULL);
gdb_assert (gdbarch->fast_tracepoint_valid_at != NULL);