diff --git a/src/acconfig.h b/src/acconfig.h
index 1ba4e8495bab49f19528264e474044e4797f4ee5..92f230b212f454d816c0432c39c5bcf8f5b90811 100644
--- a/src/acconfig.h
+++ b/src/acconfig.h
@@ -1,5 +1,5 @@
 /*
- * $Id: acconfig.h,v 1.36 1999/01/07 13:59:56 hubbe Exp $
+ * $Id: acconfig.h,v 1.37 1999/02/06 19:00:44 grubba Exp $
  */
 #ifndef MACHINE_H
 #define MACHINE_H
@@ -15,6 +15,9 @@
 /* Define this if you want run time self tests */
 #undef PIKE_DEBUG
 
+/* Define this if you are going to use a memory access checker (like Purify) */
+#undef __CHECKER__
+
 /* Define this if you want malloc debugging */
 #undef DEBUG_MALLOC