Using something like
(for old-val = (atomic-decf ...))
in SBCL gives a warning that (sb-ext:truly-the ...) isn't known.
So perhaps there should be a
#+sbcl (sb-ext:truly-the . walk-cddr)
just below the "the" handling case.
I've reported that as https://bugs.launchpad.net/sbcl/+bug/771673, too.
Regards,
Phil
--
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