diff --git a/ext/bsdcontrol.rb/context.h b/ext/bsdcontrol.rb/context.h
index e262313..ea83079 100644
--- a/ext/bsdcontrol.rb/context.h
+++ b/ext/bsdcontrol.rb/context.h
@@ -5,6 +5,6 @@ struct bsdcontrol_ctx_t {
   hbsdctrl_ctx_t *ctx;
 };
 
-VALUE bsdcontrol_context_alloc(VALUE klass);
-VALUE bsdcontrol_context_library_version(VALUE self);
-VALUE bsdcontrol_context_available_features(VALUE self);
+VALUE bsdcontrol_context_alloc(VALUE);
+VALUE bsdcontrol_context_library_version(VALUE);
+VALUE bsdcontrol_context_available_features(VALUE);