diff --git a/src/fns.c b/src/fns.c
index ef6922c137b..0ad27dbc256 100644
--- a/src/fns.c
+++ b/src/fns.c
@@ -1924,6 +1924,15 @@ The value is actually the tail of LIST whose car is ELT.  */)
   return Qnil;
 }
 
+Lisp_Object
+memq_no_quit (Lisp_Object elt, Lisp_Object list)
+{
+  for (; CONSP (list); list = XCDR (list))
+    if (EQ (XCAR (list), elt))
+      return list;
+  return Qnil;
+}
+
 DEFUN ("memql", Fmemql, Smemql, 2, 2, 0,
        doc: /* Return non-nil if ELT is an element of LIST.  Comparison done with `eql'.
 The value is actually the tail of LIST whose car is ELT.  */)
diff --git a/src/lisp.h b/src/lisp.h
index 832a1755c04..bf6b023fc2a 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -4340,6 +4340,7 @@ extern Lisp_Object plist_put (Lisp_Object plist, Lisp_Object prop,
 extern Lisp_Object plist_member (Lisp_Object plist, Lisp_Object prop);
 extern void syms_of_fns (void);
 extern void mark_fns (void);
+Lisp_Object memq_no_quit (Lisp_Object elt, Lisp_Object list);
 
 /* Defined in sort.c  */
 extern void tim_sort (Lisp_Object, Lisp_Object, Lisp_Object *, const ptrdiff_t,
diff --git a/src/xdisp.c b/src/xdisp.c
index 91db3a87aae..ceb727d1135 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -17455,7 +17455,7 @@ redisplay_internal (void)
 
 	      /* Remember tty root frames which we've seen.  */
 	      if (!FRAME_PARENT_FRAME (f)
-		  && NILP (assq_no_quit (frame, tty_root_frames)))
+		  && NILP (memq_no_quit (frame, tty_root_frames)))
 		tty_root_frames = Fcons (frame, tty_root_frames);
 	    }