diff --git a/src/OT/Layout/Common/Coverage.hh b/src/OT/Layout/Common/Coverage.hh
index a7befd61c..000e78146 100644
--- a/src/OT/Layout/Common/Coverage.hh
+++ b/src/OT/Layout/Common/Coverage.hh
@@ -225,7 +225,7 @@ struct Coverage
     static constexpr bool is_sorted_iterator = true;
     iter_t (const Coverage &c_ = Null (Coverage))
     {
-      memset (this, 0, sizeof (*this));
+      hb_memset (this, 0, sizeof (*this));
       format = c_.u.format;
       switch (format)
       {
diff --git a/src/hb-buffer-deserialize-json.rl b/src/hb-buffer-deserialize-json.rl
index d5e3c138d..d6fbfe89c 100644
--- a/src/hb-buffer-deserialize-json.rl
+++ b/src/hb-buffer-deserialize-json.rl
@@ -36,8 +36,8 @@ alphtype unsigned char;
 write data;
 
 action clear_item {
-	memset (&info, 0, sizeof (info));
-	memset (&pos , 0, sizeof (pos ));
+	hb_memset (&info, 0, sizeof (info));
+	hb_memset (&pos , 0, sizeof (pos ));
 }
 
 action add_item {
diff --git a/src/hb-buffer-deserialize-text.rl b/src/hb-buffer-deserialize-text.rl
index f7399018d..f82d5ab82 100644
--- a/src/hb-buffer-deserialize-text.rl
+++ b/src/hb-buffer-deserialize-text.rl
@@ -36,8 +36,8 @@ alphtype unsigned char;
 write data;
 
 action clear_item {
-	memset (&info, 0, sizeof (info));
-	memset (&pos , 0, sizeof (pos ));
+	hb_memset (&info, 0, sizeof (info));
+	hb_memset (&pos , 0, sizeof (pos ));
 }
 
 action add_item {