GCable symbol and keyword may cause an error (or SEGV)

[Takashi Kato]

Reported by Seth Alves.

Part of original message.

I'm hitting a bug in Sagittarius, but I'm having a hard time nailing it down.  Would you mind checking this out:

  https://github.com/sethalves/snow2-client

and running:

  ./snow2-client-sagittarius.scm search '(seth snow2 types)'

Since 0.5.10, Sagittarius has GCable symbol and keyword and their table (weak hashtable) causes this error during its finalizer invocation. (if the key is string and it's already GCed.) There are 2 ways to avoid this:

1. check if the key is still string when the table requires string key
2. add extra flag not to raise an error when key requirement doesn't match

To think about generic hashtable, option #2 would be better.

[Takashi Kato]

Adding extra argument to hash/treemap core search C API. Modifying value_finalizer not to raise an error when key is GCed (Fixes #91)

→ <<cset a9fc2012e0ab>>