This behaviour is expected according to `test-ol/make-string'.
---
lisp/ol.el | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/lisp/ol.el b/lisp/ol.el
index 1837bf37c..2e954a57f 100644
--- a/lisp/ol.el
+++ b/lisp/ol.el
@@ -999,7 +999,9 @@ (defun org-link-make-string (link &optional description)
(replace-regexp-in-string "]\\'"
(concat "\\&" zero-width-space)
(org-trim description))))))
- (if (not (org-string-nw-p link)) description
+ (if (not (org-string-nw-p link))
+ (or description
+ (error "Empty link"))
(format "[[%s]%s]"
(org-link-escape link)
(if description (format "[%s]" description) "")))))
