1 files changed, 4 insertions, 0 deletions
diff --git a/src/syntax.c b/src/syntax.c
index f17312f..ee9fec1 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -78,6 +78,10 @@ sord_inserter_write_statement(SordInserter*      inserter,
 	SordNode* o = sord_node_from_serd_node(world, env, object,
 	                                       object_datatype, object_lang);
 
+	if (!s || !p || !o) {
+		return SERD_ERR_BAD_ARG;
+	}
+
 	const SordQuad tup = { s, p, o, g };
 	sord_add(inserter->model, tup);