diff --git a/lib/client.c b/lib/client.c
index 0481aaa0..a52bb4c3 100644
--- a/lib/client.c
+++ b/lib/client.c
@@ -730,7 +730,7 @@ check_accept:
 	}
 	lwsl_info("Allocating client RX buffer %d\n", n);
 
-	if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF,  &n, sizeof n)) {
+	if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF, (const char *)&n, sizeof n)) {
 		lwsl_warn("Failed to set SNDBUF to %d", n);
 		goto bail3;
 	}
diff --git a/lib/handshake.c b/lib/handshake.c
index 720ee685..c7989c55 100644
--- a/lib/handshake.c
+++ b/lib/handshake.c
@@ -398,7 +398,7 @@ cleanup:
 			}
 			lwsl_info("Allocating RX buffer %d\n", n);
 
-			if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF,  &n, sizeof n)) {
+			if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF, (const char *)&n, sizeof n)) {
 				lwsl_warn("Failed to set SNDBUF to %d", n);
 				goto bail;
 			}