In b1ad1a1d0266a20bb we introduced an implicit (but safe) long-to-int shortening that clang didn't like. Warning not in any released version of Tor.
@@ -3347,7 +3347,7 @@ format_helper_exit_status(unsigned char child_state, int saved_errno,
*cur++ = '\n';
*cur++ = '\0';
- res = cur - hex_errno - 1;
+ res = (int)(cur - hex_errno - 1);
goto done;