* installing *source* package ‘multiLMMsel’ ...
** this is package ‘multiLMMsel’ version ‘0.0.4’
** using staged installation
** libs
using C++ compiler: ‘Debian clang version 21.1.8 (1+b1)’
clang++-21 -std=gnu++20 -I"/home/hornik/tmp/R-d-clang-21/include" -DNDEBUG -DARMA_64BIT_WORD -I'/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/Rcpp/include' -I'/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include' -I/usr/local/include -DUSE_TYPE_CHECKING_STRICT -D_FORTIFY_SOURCE=3   -fpic  -g -O3 -Wall -pedantic   -c RcppExports.cpp -o RcppExports.o
clang++-21 -std=gnu++20 -I"/home/hornik/tmp/R-d-clang-21/include" -DNDEBUG -DARMA_64BIT_WORD -I'/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/Rcpp/include' -I'/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include' -I/usr/local/include -DUSE_TYPE_CHECKING_STRICT -D_FORTIFY_SOURCE=3   -fpic  -g -O3 -Wall -pedantic   -c main.cpp -o main.o
main.cpp:25:16: error: reference to 'span' is ambiguous
   25 |         result(span(i * m, (i + 1) * m - 1),i) = v;
      |                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:25:16: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
   25 |         result(span(i * m, (i + 1) * m - 1),i) = v;
      |                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:61:39: error: reference to 'span' is ambiguous
   61 |     arma::mat zik = Z(result_i_k - 1, span(result_k_start,result_k_end));
      |                                       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:61:39: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
   61 |     arma::mat zik = Z(result_i_k - 1, span(result_k_start,result_k_end));
      |                                       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:62:39: error: reference to 'span' is ambiguous
   62 |     arma::mat zij = Z(result_i_j - 1, span(result_j_start,result_j_end));
      |                                       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:62:39: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
   62 |     arma::mat zij = Z(result_i_j - 1, span(result_j_start,result_j_end));
      |                                       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:91:41: error: reference to 'span' is ambiguous
   91 |             arma::mat submatrix = block(span((i - 1) * q, i * q - 1),span((j - 1) * q, j * q - 1));
      |                                         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:91:41: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
   91 |             arma::mat submatrix = block(span((i - 1) * q, i * q - 1),span((j - 1) * q, j * q - 1));
      |                                         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:91:70: error: reference to 'span' is ambiguous
   91 |             arma::mat submatrix = block(span((i - 1) * q, i * q - 1),span((j - 1) * q, j * q - 1));
      |                                                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:91:70: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
   91 |             arma::mat submatrix = block(span((i - 1) * q, i * q - 1),span((j - 1) * q, j * q - 1));
      |                                                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:93:24: error: reference to 'span' is ambiguous
   93 |             big_matrix(span((i - 1) * d * q, i * d * q - 1),
      |                        ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:93:24: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
   93 |             big_matrix(span((i - 1) * d * q, i * d * q - 1),
      |                        ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:94:24: error: reference to 'span' is ambiguous
   94 |                        span((j - 1) * d * q, j * d * q - 1)) = new_block;
      |                        ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:94:24: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
   94 |                        span((j - 1) * d * q, j * d * q - 1)) = new_block;
      |                        ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:136:51: error: reference to 'span' is ambiguous
  136 |             arma::mat submatrix = Z(result_i - 1, span(result_j_start,result_j_end));
      |                                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:136:51: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
  136 |             arma::mat submatrix = Z(result_i - 1, span(result_j_start,result_j_end));
      |                                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:164:59: error: reference to 'span' is ambiguous
  164 |                     arma::mat submatrix_j = Z(result_i_j, span(result_j_start,result_j_end));
      |                                                           ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
main.cpp:164:59: error: no viable constructor or deduction guide for deduction of template arguments of 'span'
  164 |                     arma::mat submatrix_j = Z(result_i_j, span(result_j_start,result_j_end));
      |                                                           ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: candidate template ignored: couldn't infer template argument '_Type'
  185 |         span(_It __first, size_type __count)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:185:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It> requires __is_compatible_ref<iter_reference_t<_It>>::value explicit(extent != dynamic_extent) span(_It __first, size_type __count) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: candidate template ignored: couldn't infer template argument '_Type'
  194 |         span(_It __first, _End __last)
      |         ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:194:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, contiguous_iterator<> _It, sized_sentinel_for<_It> _End> requires __is_compatible_ref<iter_reference_t<_It>>::value && (! is_convertible_v<_End, size_type>) explicit(extent != dynamic_extent) span(_It __first, _End __last) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:492:5: note: candidate template ignored: constraints not satisfied [with _Iter = int, _End = int]
  492 |     span(_Iter, _End)
      |     ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:491:12: note: because 'int' does not satisfy 'contiguous_iterator'
  491 |   template<contiguous_iterator _Iter, typename _End>
      |            ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:735:35: note: because 'int' does not satisfy 'random_access_iterator'
  735 |     concept contiguous_iterator = random_access_iterator<_Iter>
      |                                   ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:719:38: note: because 'int' does not satisfy 'bidirectional_iterator'
  719 |     concept random_access_iterator = bidirectional_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:709:38: note: because 'int' does not satisfy 'forward_iterator'
  709 |     concept bidirectional_iterator = forward_iterator<_Iter>
      |                                      ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:704:32: note: because 'int' does not satisfy 'input_iterator'
  704 |     concept forward_iterator = input_iterator<_Iter>
      |                                ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:693:30: note: because 'int' does not satisfy 'input_or_output_iterator'
  693 |     concept input_iterator = input_or_output_iterator<_Iter>
      |                              ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/iterator_concepts.h:672:33: note: because '*__i' would be invalid: indirection requires pointer operand ('int' invalid)
  672 |       = requires(_Iter __i) { { *__i } -> __detail::__can_reference; }
      |                                 ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  203 |         span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:203:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, size_t _ArrayExtent> requires (_Extent == dynamic_extent || _ArrayExtent == _Extent) span(type_identity_t<element_type> (&__arr)[_ArrayExtent]) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  210 |         span(array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:210:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<_Tp, _ArrayExtent>::value span(array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: candidate function template not viable: requires single argument '__arr', but 2 arguments were provided
  217 |         span(const array<_Tp, _ArrayExtent>& __arr) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:217:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Tp, size_t _ArrayExtent> requires __is_compatible_array<const _Tp, _ArrayExtent>::value span(const array<_Tp, _ArrayExtent> &__arr) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: candidate function template not viable: requires single argument '__range', but 2 arguments were provided
  229 |         span(_Range&& __range)
      |         ^    ~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:229:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _Range> requires (! __detail::__is_span<remove_cvref_t<_Range>>) && (! __detail::__is_std_array<remove_cvref_t<_Range>>) && (! is_array_v<remove_cvref_t<_Range>>) && ranges::contiguous_range<_Range> && ranges::sized_range<_Range> && (ranges::borrowed_range<_Range> || is_const_v<element_type>) && __is_compatible_ref<ranges::range_reference_t<_Range>>::value explicit(extent != dynamic_extent) span(_Range &&__range) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: candidate function template not viable: requires 1 argument, but 2 were provided
  248 |       span(const span&) noexcept = default;
      |       ^    ~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:248:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(const span<_Type, _Extent> &) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: candidate function template not viable: requires single argument '__s', but 2 arguments were provided
  256 |         span(const span<_OType, _OExtent>& __s) noexcept
      |         ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:256:2: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent, typename _OType, size_t _OExtent> requires (_Extent == dynamic_extent || _OExtent == dynamic_extent || _Extent == _OExtent) && (__is_array_convertible<_Type, _OType>::value) explicit(extent != dynamic_extent && _OExtent == dynamic_extent) span(const span<_OType, _OExtent> &__s) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: candidate function template not viable: requires single argument '__ptr', but 2 arguments were provided
  470 |       span(_SizedPtr __ptr) noexcept
      |       ^    ~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:470:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> explicit span(_SizedPtr __ptr) -> span<_Type, _Extent> requires (extent != dynamic_extent)'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate function template not viable: requires 1 argument, but 2 were provided
  124 |     class span
      |           ^~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span(span<_Type, _Extent>) -> span<_Type, _Extent>'
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:482:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  482 |     span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:485:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  485 |     span(array<_Type, _ArrayExtent>&) -> span<_Type, _ArrayExtent>;
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:488:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  488 |     span(const array<_Type, _ArrayExtent>&)
      |     ^    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:496:5: note: candidate function template not viable: requires 1 argument, but 2 were provided
  496 |     span(_Range &&)
      |     ^    ~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: candidate function template not viable: requires 0 arguments, but 2 were provided
  177 |       span() noexcept
      |       ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:177:7: note: implicit deduction guide declared as 'template <typename _Type, size_t _Extent = dynamic_extent> span() -> span<_Type, _Extent> requires (_Extent == dynamic_extent || _Extent == 0)'
main.cpp:165:59: error: reference to 'span' is ambiguous
  165 |                     arma::mat submatrix_k = Z(result_i_k, span(result_k_start,result_k_end));
      |                                                           ^
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/span:124:11: note: candidate found by name lookup is 'std::span'
  124 |     class span
      |           ^
/home/hornik/lib/R/Library/4.6/x86_64-linux-gnu/RcppArmadillo/include/current/armadillo_bits/span.hpp:38:8: note: candidate found by name lookup is 'arma::span'
   38 | struct span : public span_base<>
      |        ^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
make: *** [/home/hornik/tmp/R-d-clang-21/etc/Makeconf:201: main.o] Error 1
ERROR: compilation failed for package ‘multiLMMsel’
* removing ‘/srv/hornik/tmp/CRAN_pretest/multiLMMsel.Rcheck/multiLMMsel’