diff --git a/lisp/progmodes/cc-fonts.el b/lisp/progmodes/cc-fonts.el
index fa9b8f354ef..39d167f0190 100644
--- a/lisp/progmodes/cc-fonts.el
+++ b/lisp/progmodes/cc-fonts.el
@@ -1279,12 +1279,14 @@ casts and declarations are fontified.  Used on level 2 and higher."
 	   (c-put-char-property (1- match-pos)
 				'c-type 'c-decl-arg-start)
 	   (cons 'decl nil))
-	  ;; Got an open paren preceded by an arith operator.
+	  ;; Got (an) open paren(s) preceded by an arith operator.
 	  ((and (eq (char-before match-pos) ?\()
 		(save-excursion
 		  (goto-char match-pos)
-		  (and (zerop (c-backward-token-2 2))
-		       (looking-at c-arithmetic-op-regexp))))
+		  (while
+		      (progn (c-backward-token-2)
+			     (eq (char-after) ?\()))
+		  (looking-at c-arithmetic-op-regexp)))
 	   (cons nil nil))
 	  ;; In a C++ member initialization list.
 	  ((and (eq (char-before match-pos) ?,)