int compare_commits_by_gen_then_commit_date(const void *a_, const void *b_, void *unused)
{
const struct commit *a = a_, *b = b_;
- const uint32_t generation_a = commit_graph_generation(a),
- generation_b = commit_graph_generation(b);
+ const timestamp_t generation_a = commit_graph_generation(a),
+ generation_b = commit_graph_generation(b);
/* newer commits first */
if (generation_a < generation_b)