Re: Refcount struct dictionary ?

[Ben Pfaff]

On Sun, Sep 23, 2018 at 03:02:34PM +0200, John Darrington wrote:
> The following patch fixes some (potentially fatal) use-after-free errors in 
> the gui.
> It does however do a lot more copying of dictionary which is in most 
> instances 
> unnecessary.
> 
> An alternative would be to refcount the dictionary in much the same way as we 
> do
> struct ccase.

It seems like refcounting the dictionary will require a lot of care to
find all the places where a dictionary gets modified to un-share.  I
seem to recall that the variables in a dictionary have a reference
upward to the dictionary, too.

I'm not saying that refcounting the dictionary is the wrong choice but
it needs to be done carefully.