```cpp
#if defined(_LIBUNWIND_TARGET_X86_64)
  addr_t signal_handler = (((addr_t*)__gCommPageAddress)[COMMPAGE_ENTRY_X86_SIGNAL_HANDLER] + (addr_t)__gCommPageAddress);
  addr_t signal_handler_ret = signal_handler + 45;
#endif
```

again, how did you get these magic numbers?
(for signal frame unwinding on libunwind)