bug#23926: defcustom with STANDARD=<non-pure-expression> gives confusing results

[npostavs]

Eli Zaretskii <eliz@gnu.org> writes:
> Of course, I do.  Maybe you don't realize how many times Emacs
> evaluates the value of a defcustom, but I do.

What about making Emacs evaluate it less? e.g. replace occurences of
(eval (car (get var 'standard-value))) with

(or (get var 'original-value)
    (let ((val (eval (car (get var 'standard-value)))))
      (put var 'original-value val)
      val))

Wrapped in a function of course, call it custom-get-standard-value?