diff --git a/libiptc/libiptc.c b/libiptc/libiptc.c
index f0f7815..004b0ec 100644
--- a/libiptc/libiptc.c
+++ b/libiptc/libiptc.c
@@ -502,7 +502,8 @@ static int iptcc_chain_index_alloc(struct xtc_handle *h)
 	h->chain_index = malloc(array_mem);
 	if (h->chain_index == NULL && array_mem > 0) {
 		h->chain_index_sz = 0;
-		return -ENOMEM;
+		errno = ENOMEM;
+		return -1;
 	}
 	memset(h->chain_index, 0, array_mem);
 	h->chain_index_sz = array_elems;