DEFSTRUCT should signal error/warning if :PREDICATE + :TYPE without :NAMED

[Tobias C. Rittweiler]

CLHS says

  A predicate can be defined only if the structure is named;
  if :type is supplied and :named is not supplied, then
  :predicate must either be unsupplied or have the value nil.

Yet SBCL compiles

(defstruct (typed-struct (:type list) (:predicate typed-struct-p))
  (a 42 :type fixnum))

silently, and it seems to ignore the :PREDICATE clause.

[Roman Marynchak (roman-marynchak)]

The patch for this problem, with the regression test.

[Nikodemus Siivola (nikodemus)]

Doesn't handle

  (defstruct (foo (:type list) (:predicate nil)))

correctly.

[Nikodemus Siivola (nikodemus)]

Adjusted patch in my pending tree.

[Nikodemus Siivola (nikodemus)]

In 1.0.46.9.