object: validate that `odb_obj` was set
diff --git a/src/libgit2/object.c b/src/libgit2/object.c
index 7bc256f..b828f88 100644
--- a/src/libgit2/object.c
+++ b/src/libgit2/object.c
@@ -250,6 +250,7 @@ int git_object_lookup_prefix(
if (error < 0)
return error;
+ GIT_ASSERT(odb_obj);
error = git_object__from_odb_object(object_out, repo, odb_obj, type);
git_odb_object_free(odb_obj);