--- src/render.c.orig	2002-04-11 09:50:46.000000000 +0900
+++ src/render.c	2020-11-21 15:53:11.000000000 +0900
@@ -60,6 +60,7 @@
 #include "v5d.h"
 
 extern int vis5d_verbose;
+extern void stereo_set_buff( int );
 
 #define MAX(A,B)  ( (A) > (B) ? (A) : (B) )
 #define MIN(A,B)  ( (A) < (B) ? (A) : (B) )