1 files changed, 1 insertions, 1 deletions
diff --git a/object.c b/object.c
index 97419b03d6..3bcad9fea7 100644
--- a/object.c
+++ b/object.c
@@ -1519,7 +1519,7 @@ rb_class_inherited_p(VALUE mod, VALUE arg)
     VALUE start = mod;
 
     if (mod == arg) return Qtrue;
-    if (!CLASS_OR_MODULE_P(arg)) {
+    if (!CLASS_OR_MODULE_P(arg) && !RB_TYPE_P(arg, T_ICLASS)) {
 	rb_raise(rb_eTypeError, "compared with non class/module");
     }
     arg = RCLASS_ORIGIN(arg);