 
     // Determine the right place to output this buffer.
     if (cg_group.thread_rank() == 0) {
-      static_assert(sizeof(uint64_t) == sizeof(unsigned long long int));
-      compression_args.comp_chunk_offsets[this_ix_chunk] = atomicAdd(
+        static_assert(sizeof(uint64_t) == sizeof(unsigned long long int),
+          "The cast below requires that the sizes are the same.");
+        compression_args.comp_chunk_offsets[this_ix_chunk] = atomicAdd(
           reinterpret_cast<unsigned long long int*>(compression_args.ix_output), 
           compression_args.comp_chunk_sizes[this_ix_chunk]);
     }

#include <cassert>
#include <cooperative_groups.h>
#include <stdio.h>

#include "nvcomp/shared_types.h"
#include "hlif_shared_types.hpp"

    CompressT&& compressor,
    GroupT&& cg_group)
{
  if (blockIdx.x == 0 && cg::this_thread_block().thread_rank() == 0) {
    fill_common_header(
        compression_args, 
        compressor.get_format_type());
