diff --git a/libguile/tags.h b/libguile/tags.h
index 4192b4778..cc37e704e 100644
--- a/libguile/tags.h
+++ b/libguile/tags.h
@@ -439,6 +439,8 @@ enum scm_tags
 #define SCM_MAKISYM(n) 		(((n)<<9)+0x74L)
 #define SCM_MAKIFLAG(n) 	(((n)<<9)+0x174L)
 
+extern char *scm_isymnames[];   /* defined in print.c */
+
 /* This table must agree with the declarations
  * in repl.c: {Names of immediate symbols}.
  *