* lisp/emacs-lisp/syntax.el (syntax-begin-function): Make obsolete

etc/NEWS

@@ -867,7 +867,8 @@ a typographically-correct documents.
 
 * Incompatible Lisp Changes in Emacs 25.1
 
-** Removed font-lock-beginning-of-syntax-function and the SYNTAX-BEGIN
+** `syntax-begin-function' is declared obsolete.
+Removed font-lock-beginning-of-syntax-function and the SYNTAX-BEGIN
 slot in font-lock-defaults.
 
 +++

lisp/emacs-lisp/syntax.el

@@ -374,6 +374,7 @@ from each other, to avoid keeping too much useless info.")
   "Function to move back outside of any comment/string/paren.
 This function should move the cursor back to some syntactically safe
 point (where the PPSS is equivalent to nil).")
+(make-obsolete-variable 'syntax-begin-function nil "25.1")
 
 (defvar syntax-ppss-cache nil
   "List of (POS . PPSS) pairs, in decreasing POS order.")