(define (read-response-v2-body port backend operation)
  (let ((response-length (read-response-v2 port backend operation)))
    (if response-length
        (read-u8vector response-length port)
        #f)))


  /home/alaric/chickens/master/bin/csc -feature compiling-extension -setup-mode    -s -O3 -d1 ugarit-backend.scm -j ugarit-backend

Warning: in toplevel procedure `ugarit-backend#read-response-v2-body':
  access to variable `response-length' which has an undefined value

Warning: in toplevel procedure `ugarit-backend#read-response-v2-body':
  access to variable `response-length' which has an undefined value

(define (read-response-v2 port backend operation)
  (let ((response (read port)))
   (match response
          (("error" err) (protocol-error (sprintf "Error from backend: ~s" err) backend operation))
          ((log value)
           (for-each (lambda (logentry)
                       ((backend-log!) (car logentry) (cdr logentry)))
                     log)
           value)
          ((log)
           (for-each (lambda (logentry)
                       ((backend-log!) (car logentry) (cdr logentry)))
                     log)
           (void))
          (else (error "Malformed response from backend" response)))))