diff --git a/libguile/ChangeLog b/libguile/ChangeLog
index eb8a51143..8123b7241 100644
--- a/libguile/ChangeLog
+++ b/libguile/ChangeLog
@@ -1,3 +1,8 @@
+2001-01-29  Mikael Djurfeldt  <mdj@linnaeus.mit.edu>
+
+	* eval.c (SCM_APPLY): Check that primitives which take 1 arg
+	really get that arg.
+
 2001-01-26  Keisuke Nishida  <kxn30@po.cwru.edu>
 
 	* goops.c (s_scm_get_keyword): Bug fix.
diff --git a/libguile/eval.c b/libguile/eval.c
index 62bef0b4b..eaef7570e 100644
--- a/libguile/eval.c
+++ b/libguile/eval.c
@@ -3302,6 +3302,7 @@ tail:
       SCM_ASRTGO (SCM_UNBNDP (arg1), wrongnumargs);
       RETURN (SCM_SUBRF (proc) ())
     case scm_tc7_subr_1:
+      SCM_ASRTGO (!SCM_UNBNDP (arg1), wrongnumargs);
     case scm_tc7_subr_1o:
       SCM_ASRTGO (SCM_NULLP (args), wrongnumargs);
       RETURN (SCM_SUBRF (proc) (arg1))