- (let ((prognlist ()))
- (while forms
- (let* ((sym (pop forms))
- (sym-new (or (cdr (assq sym env)) sym))
- (value-in-list
- (and forms
- (list (cconv-convert (pop forms) env extend)))))
- (push (pcase sym-new
- ((pred symbolp) `(setq ,sym-new ,@value-in-list))
- (`(car-safe ,iexp) `(setcar ,iexp ,@value-in-list))
- ;; This "should never happen", but for variables which are
- ;; mutated+captured+unused, we may end up trying to `setq'
- ;; on a closed-over variable, so just drop the setq.
- (_ ;; (byte-compile-report-error
- ;; (format "Internal error in cconv of (setq %s ..)"
- ;; sym-new))
- (car value-in-list)))
- prognlist)))
- (if (cdr prognlist)
- `(progn . ,(nreverse prognlist))
- (car prognlist))))
+ (if (= (logand (length forms) 1) 1)
+ ;; With an odd number of args, let bytecomp.el handle the error.
+ form
+ (let ((prognlist ()))
+ (while forms
+ (let* ((sym (pop forms))
+ (sym-new (or (cdr (assq sym env)) sym))
+ (value (cconv-convert (pop forms) env extend)))
+ (push (pcase sym-new
+ ((pred symbolp) `(setq ,sym-new ,value))
+ (`(car-safe ,iexp) `(setcar ,iexp ,value))
+ ;; This "should never happen", but for variables which are
+ ;; mutated+captured+unused, we may end up trying to `setq'
+ ;; on a closed-over variable, so just drop the setq.
+ (_ ;; (byte-compile-report-error
+ ;; (format "Internal error in cconv of (setq %s ..)"
+ ;; sym-new))
+ value))
+ prognlist)))
+ (if (cdr prognlist)
+ `(progn . ,(nreverse prognlist))
+ (car prognlist)))))