Found the following significant warnings:
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/concurrent_vector.h:88:20: warning: ‘void* memset(void*, int, size_t)’ clearing an object of type ‘class std::tuple<unsigned int, unsigned int, double>’ with no trivial copy-assignment; use assignment instead [-Wclass-memaccess]
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/internal/_concurrent_unordered_impl.h:1481:24: warning: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘tbb::interface5::internal::concurrent_unordered_base<tbb::interface5::concurrent_unordered_set_traits<std::vector<unsigned int>, tbb::interface5::internal::hash_compare<std::vector<unsigned int>, quanteda::hash_ngram, quanteda::equal_ngram>, tbb::tbb_allocator<std::vector<unsigned int> >, false> >::raw_iterator’ {aka ‘class tbb::interface5::internal::flist_iterator<tbb::interface5::internal::split_ordered_list<std::vector<unsigned int>, tbb::tbb_allocator<std::vector<unsigned int> > >, std::vector<unsigned int> >’}; use assignment or value-initialization instead [-Wclass-memaccess]
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/internal/_concurrent_unordered_impl.h:1481:24: warning: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘tbb::interface5::internal::concurrent_unordered_base<tbb::interface5::concurrent_unordered_map_traits<std::vector<unsigned int>, tbb::atomic<unsigned int>, tbb::interface5::internal::hash_compare<std::vector<unsigned int>, quanteda::hash_ngram, quanteda::equal_ngram>, tbb::tbb_allocator<std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> > >, false> >::raw_iterator’ {aka ‘class tbb::interface5::internal::flist_iterator<tbb::interface5::internal::split_ordered_list<std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> >, tbb::tbb_allocator<std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> > > >, std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> > >’}; use assignment or value-initialization instead [-Wclass-memaccess]
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/internal/_concurrent_unordered_impl.h:1481:24: warning: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘tbb::interface5::internal::concurrent_unordered_base<tbb::interface5::concurrent_unordered_map_traits<std::vector<unsigned int>, std::pair<tbb::atomic<unsigned int>, tbb::atomic<unsigned int> >, tbb::interface5::internal::hash_compare<std::vector<unsigned int>, quanteda::hash_ngram, quanteda::equal_ngram>, tbb::tbb_allocator<std::pair<const std::vector<unsigned int>, std::pair<tbb::atomic<unsigned int>, tbb::atomic<unsigned int> > > >, false> >::raw_iterator’ {aka ‘class tbb::interface5::internal::flist_iterator<tbb::interface5::internal::split_ordered_list<std::pair<const std::vector<unsigned int>, std::pair<tbb::atomic<unsigned int>, tbb::atomic<unsigned int> > >, tbb::tbb_allocator<std::pair<const std::vector<unsigned int>, std::pair<tbb::atomic<unsigned int>, tbb::atomic<unsigned int> > > > >, std::pair<const std::vector<unsigned int>, std::pair<tbb::atomic<unsigned int>, tbb::atomic<unsigned int> > > >’}; use assignment or value-initialization instead [-Wclass-memaccess]
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/concurrent_vector.h:88:20: warning: ‘void* memset(void*, int, size_t)’ clearing an object of type ‘struct std::pair<std::vector<unsigned int>, tbb::atomic<unsigned int> >’ with no trivial copy-assignment; use assignment instead [-Wclass-memaccess]
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/concurrent_vector.h:88:20: warning: ‘void* memset(void*, int, size_t)’ clearing an object of type ‘class std::vector<unsigned int>’ with no trivial copy-assignment; use assignment or value-initialization instead [-Wclass-memaccess]
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/internal/_concurrent_unordered_impl.h:1481:24: warning: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘tbb::interface5::internal::concurrent_unordered_base<tbb::interface5::concurrent_unordered_set_traits<unsigned int, tbb::interface5::internal::hash_compare<unsigned int, tbb::tbb_hash<unsigned int>, std::equal_to<unsigned int> >, tbb::tbb_allocator<unsigned int>, false> >::raw_iterator’ {aka ‘class tbb::interface5::internal::flist_iterator<tbb::interface5::internal::split_ordered_list<unsigned int, tbb::tbb_allocator<unsigned int> >, unsigned int>’}; use assignment or value-initialization instead [-Wclass-memaccess]
  /home/hornik/tmp/R.check/r-release-gcc/Work/build/Packages/RcppParallel/include/tbb/internal/_concurrent_unordered_impl.h:1481:24: warning: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘tbb::interface5::internal::concurrent_unordered_base<tbb::interface5::concurrent_unordered_map_traits<std::vector<unsigned int>, tbb::atomic<unsigned int>, tbb::interface5::internal::hash_compare<std::vector<unsigned int>, quanteda::hash_ngram, quanteda::equal_ngram>, tbb::tbb_allocator<std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> > >, true> >::raw_iterator’ {aka ‘class tbb::interface5::internal::flist_iterator<tbb::interface5::internal::split_ordered_list<std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> >, tbb::tbb_allocator<std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> > > >, std::pair<const std::vector<unsigned int>, tbb::atomic<unsigned int> > >’}; use assignment or value-initialization instead [-Wclass-memaccess]
See ‘/home/hornik/tmp/R.check/r-release-gcc/Work/PKGS/quanteda.Rcheck/00install.out’ for details.