Fix warnings
diff --git a/src/hb-open-type-private.hh b/src/hb-open-type-private.hh
index 52afd6b..adbd4c7 100644
--- a/src/hb-open-type-private.hh
+++ b/src/hb-open-type-private.hh
@@ -154,7 +154,7 @@
};
template <> /* Optimize when tracing is disabled */
struct hb_trace_t<0> {
- explicit hb_trace_t (unsigned int *pdepth, const char *what, const char *function, const void *obj) {}
+ explicit hb_trace_t (unsigned int *pdepth HB_UNUSED, const char *what HB_UNUSED, const char *function HB_UNUSED, const void *obj HB_UNUSED) {}
};