Apply Clang's padding advice to structures.

src/engine.c

@@ -2434,7 +2434,7 @@ void engine_collect_timestep(struct engine *e) {
     ti_end_min = in_i[0];
   }
   {
-    unsigned long long in_ll[2], out_ll[2];
+    long long in_ll[2], out_ll[2];
     out_ll[0] = updates;
     out_ll[1] = g_updates;
     if (MPI_Allreduce(out_ll, in_ll, 2, MPI_LONG_LONG_INT, MPI_SUM,

src/gravity/Default/gravity_part.h

@@ -25,6 +25,10 @@
 /* Gravity particle. */
 struct gpart {
 
+  /* Particle ID. If negative, it is the negative offset of the #part with
+     which this gpart is linked. */
+  long long id_or_neg_offset;
+
   /* Particle position. */
   double x[3];
 
@@ -49,10 +53,6 @@ struct gpart {
   /* Particle time of end of time-step. */
   int ti_end;
 
-  /* Particle ID. If negative, it is the negative offset of the #part with
-     which this gpart is linked. */
-  long long id_or_neg_offset;
-
 } SWIFT_STRUCT_ALIGN;
 
 #endif /* SWIFT_DEFAULT_GRAVITY_PART_H */

src/threadpool.h

@@ -32,9 +32,6 @@ typedef void (*threadpool_map_function)(void *map_data, int num_elements,
 /* Data of a threadpool. */
 struct threadpool {
 
-  /* Number of threads in this pool. */
-  int num_threads;
-
   /* The threads themselves. */
   pthread_t *threads;
 
@@ -48,6 +45,9 @@ struct threadpool {
       map_data_chunk;
   volatile threadpool_map_function map_function;
 
+  /* Number of threads in this pool. */
+  int num_threads;
+
   /* Counter for the number of threads that are done. */
   volatile int num_threads_waiting, num_threads_running;
 };