gc crash caused by improper use of GC_general_register_disappearing_link

Fri Nov 12 18:35:00 GMT 2004

I had a crash inside the gc. It turns out that someone made a weak
reference to an instance of class Class. However, some instances of
Class are statically allocated, and the doc for
GC_general_register_disappearing_link says
"Obj must be a pointer to the first word of an object we allocated."
So, this call to GC_general_register_disappearing_link is illegal. 
Is there some reasonably easy way we can do something like
 if (thing points to something that is gc allocated)
 GC_general_register_disappearing_link(thing)
We intend to heap allocate instances of Class in the future, but I'd
prefer not to have to do so right now.
Thanks,
Andrew.