(cl-defstruct): Improve handling of unknown options

Until now `cl-defstruct` signaled an error when encountering an
unknown option.  It's easy to code and it does the job, but it
doesn't give good location info in the compiler's output,
and it makes it more painful to use not-yet-supported options.
So just signal a warning instead.

* lisp/emacs-lisp/cl-macs.el (cl-defstruct): Warn about unknown
options, instead of signaling an error.

(cherry picked from commit 484b0979099d91e286c248e32b2f693111fac2ad)

diff --git a/lisp/emacs-lisp/cl-macs.el b/lisp/emacs-lisp/cl-macs.el
index 1350e474d6aebdd28703d4d2c7f6934e49992855..2e501005bf7cab13a715e5aad1dae95472f53eba 100644 (file)
--- a/lisp/emacs-lisp/cl-macs.el
+++ b/lisp/emacs-lisp/cl-macs.el
@@ -3010,6 +3010,7 @@ To see the documentation for a defined struct type, use
              ;; All the above is for the following def-form.
              &rest &or symbolp (symbolp &optional def-form &rest sexp))))
   (let* ((name (if (consp struct) (car struct) struct))
+        (warning nil)
         (opts (cdr-safe struct))
         (slots nil)
         (defaults nil)
@@ -3094,7 +3095,10 @@ To see the documentation for a defined struct type, use
               (setq descs (nconc (make-list (car args) '(cl-skip-slot))
                                  descs)))
              (t
-              (error "Structure option %s unrecognized" opt)))))
+              (setq warning
+                    (macroexp-warn-and-return
+                     (format "Structure option %S unrecognized" opt)
+                     warning nil nil (list opt struct)))))))
     (unless (or include-name type
                 ;; Don't create a bogus parent to `cl-structure-object'
                 ;; while compiling the (cl-defstruct cl-structure-object ..)
@@ -3333,6 +3337,7 @@ To see the documentation for a defined struct type, use
          (cl-struct-define ',name ,docstring ',include-name
                            ',(or type 'record) ,(eq named t) ',descs
                            ',tag-symbol ',tag ',print-auto))
+       ,warning
        ',name)))
 
 ;;; Add cl-struct support to pcase