thodg/libgit2

diff --git a/src/delta.c b/src/delta.c
index 1ff7752..2d2c5fa 100644
--- a/src/delta.c
+++ b/src/delta.c
@@ -256,7 +256,7 @@ void git_delta_index_free(git_delta_index *index)
 
 size_t git_delta_index_size(git_delta_index *index)
 {
-	assert(index);
+	GIT_ASSERT_ARG(index);
 
 	return index->memsize;
 }