diff --git a/src/engine.c b/src/engine.c
index 6fdc5ee88e1343d4ce0c53e7a346729207d41b4b..289f488461f8fc7897f079c1e5d7431b5a78ac83 100644
--- a/src/engine.c
+++ b/src/engine.c
@@ -133,7 +133,7 @@ struct end_of_step_data {
 void engine_addlink(struct engine *e, struct link **l, struct task *t) {
 
   /* Get the next free link. */
-  const int ind = atomic_inc(&e->nr_links);
+  const size_t ind = atomic_inc(&e->nr_links);
   if (ind >= e->size_links) {
     error("Link table overflow.");
   }
@@ -3105,15 +3105,15 @@ void engine_maketasks(struct engine *e) {
  * and 2 (density, force) self.
  */
 #ifdef EXTRA_HYDRO_LOOP
-  const int hydro_tasks_per_cell = 27 * 3;
+  const size_t hydro_tasks_per_cell = 27 * 3;
 #else
-  const int hydro_tasks_per_cell = 27 * 2;
+  const size_t hydro_tasks_per_cell = 27 * 2;
 #endif
-  const int self_grav_tasks_per_cell = 125;
-  const int ext_grav_tasks_per_cell = 1;
+  const size_t self_grav_tasks_per_cell = 125;
+  const size_t ext_grav_tasks_per_cell = 1;
 
   if (e->policy & engine_policy_hydro)
-    e->size_links += s->tot_cells * hydro_tasks_per_cell;
+      e->size_links += s->tot_cells * hydro_tasks_per_cell;
   if (e->policy & engine_policy_external_gravity)
     e->size_links += s->tot_cells * ext_grav_tasks_per_cell;
   if (e->policy & engine_policy_self_gravity)
@@ -5436,7 +5436,6 @@ void engine_init(struct engine *e, struct space *s, struct swift_params *params,
       parser_get_param_double(params, "Statistics:delta_time");
   e->ti_next_stats = 0;
   e->verbose = verbose;
-  e->count_step = 0;
   e->wallclock_time = 0.f;
   e->physical_constants = physical_constants;
   e->cosmology = cosmo;
diff --git a/src/engine.h b/src/engine.h
index 7fdc3c9b3ddffbc19065ca2eaddfa9759261d3c8..064493df710ed2d67607f302c19f7cb41a56bc57 100644
--- a/src/engine.h
+++ b/src/engine.h
@@ -234,9 +234,6 @@ struct engine {
   /* The current step number. */
   int step;
 
-  /* The number of particles updated in the previous step. */
-  int count_step;
-
   /* Data for the threads' barrier. */
   swift_barrier_t wait_barrier;
   swift_barrier_t run_barrier;
@@ -282,11 +279,11 @@ struct engine {
 
   /* Linked list for cell-task association. */
   struct link *links;
-  int nr_links, size_links;
+  size_t nr_links, size_links;
 
   /* Average number of tasks per cell. Used to estimate the sizes
    * of the various task arrays. */
-  int tasks_per_cell;
+  size_t tasks_per_cell;
 
   /* Are we talkative ? */
   int verbose;