diff --git a/girepository/gitypelib.c b/girepository/gitypelib.c
index 3c88a79e6..57411a86b 100644
--- a/girepository/gitypelib.c
+++ b/girepository/gitypelib.c
@@ -316,7 +316,8 @@ strsplit_iter_next (StrSplitIter  *iter,
     }
   else
     {
-      g_string_overwrite_len (&iter->buf, 0, s, (gssize)len);
+      g_string_overwrite_len (&iter->buf, 0, s, (gssize)len + 1);
+      iter->buf.str[len] = '\0';
       *out_val = iter->buf.str;
     }
   return TRUE;