diff --git a/test/api/test-font.c b/test/api/test-font.c
index 5ceb131..3d81cf9 100644
--- a/test/api/test-font.c
+++ b/test/api/test-font.c
@@ -367,7 +367,7 @@
 static hb_bool_t
 nominal_glyph_func (hb_font_t *font HB_UNUSED,
 		    void *font_data HB_UNUSED,
-		    hb_codepoint_t unicode,
+		    hb_codepoint_t unicode HB_UNUSED,
 		    hb_codepoint_t *glyph,
 		    void *user_data HB_UNUSED)
 {