Debug support in fiddle?

kojix2 provides the fiddle-bindings for libui here:

https://github.com/kojix2/LibUI

Libui is very easy to use; I ported many of my ruby-gtk3 widgets already,
even though libui is quite limited compared to ruby-gtk3. Anyway, in my own
project i modify Fiddle::Pointer to fake-"simulate" OOP.

My biggest problem with fiddle so far is the debug-support. Due to doing
tons of mistakes I get lots of segfaults, and while it is fun to find out why,
in the long run I'd love to be able to more easily and quickly find the error
I did. But when things segfault, I don't seem to get good quality information.

If segfaults happen in ruby, then I often get the exact name, stack tracke
and call stack; and I can use caller(). With fiddle I do not seem to get the
same information or at the least not as much as I think may be useful.

Would it be possible to improve the debug support in fiddle in general?
Perhaps a better stack trace showing where errors happened, a bit
like how ruby does. Or perhaps I just don't know how to debug this,
in which case it would be nice if the main README could provide a
few helpful pointers. Please feel free to close this issue at any moment
in time - I understand that this may not be a trivial change but if anyone
finds some time in the future, keeping better debug-support would be
super-useful. Right now I seem to do random changes and hope for
the best. :D (See also kojix2' comment in regards to having to assign
to variables to avoid the GC terminate the program. Would be nice
if this could all become more transparent when working via ruby.)

メインのREADMEとissueで説明されているFiddle::Pointerの動作から始め、次にFiddle呼び出しで利用できるデバッグ情報をRubyのcallerおよびスタックトレースと比較します。実行可能な成果が診断の改善なのか、デバッグ手順の文書化なのかを判断します。完了とは、これらのいずれかの方針が明確に指定され、テストまたはREADMEの変更によって裏付けられていることを意味します。