diff --git a/libostree/ostree-repo.c b/libostree/ostree-repo.c
index 2d94e0d0..0d345312 100644
--- a/libostree/ostree-repo.c
+++ b/libostree/ostree-repo.c
@@ -546,7 +546,7 @@ write_gvariant_to_tmp (OstreeRepo  *self,
   char *dest_name = NULL;
   int fd = -1;
   GUnixOutputStream *stream = NULL;
-  GChecksum *checksum;
+  GChecksum *checksum = NULL;
 
   serialized = g_variant_new ("(uv)", GUINT32_TO_BE ((guint32)type), variant);