bug#36149: 26.1; "Apparently circular structure being printed" (when closing Gnus)

[Noam Postavsky]

merge 36149 31978
quit

Gour <gour@atmarama.com> writes:

> I get the message when I try to exit from the Gnus.
>
> Here is the backtrace:
>
> Debugger entered--Lisp error: (error "Apparently circular structure being 
> printed")
>   prin1(#<hash-table eql 4/100 0x469f219>)
>   eieio-override-prin1(#<hash-table eql 4/100 0x185729d>)

>   eieio-persistent-save(#<registry-db registry-db> "~/.gnus.registry.eieio")
>   gnus-registry-save()

I guess this is the same as Bug#31978.