#include <linalg> causes compiler error in VS2022 #266
Description
Putting
#include <linalg>
in a source file in Visual Studio 2022, using the VS compiler, results in a compiler error. There is no error when I switch to the LLVM Platform Toolset in my project settings, however.
Details and repro follow:
My VS project name is lin_alg_examples (VS creates a directory of the same name). Under this directory, I created the following subdirectory:
...lin_alg_examples\kokkos\experimental
Under experimental, I placed the mdspan and linalg header files, and the __p0009_bits and __p1673_bits directories:
In the project settings, I am using the VS compiler with the latest C++ working draft:
I then write an empty main() function:
#include <experimental/mdspan>
#include <experimental/linalg>
#include <vector>#include <cstdlib>
#include <iostream>#include <format>
using std::vector, std::size_t, std::cout, std::format;
namespace stdex = std::experimental;
int main()
{
}
When I build the project, I get the following compiler error messages:
\lin_alg_examples\kokkos\experimental\__p1673_bits\transposed.hpp(255,57): error C2653: 'original_mapping_type': is not a class or namespace name
\lin_alg_examples\kokkos\experimental\__p1673_bits\transposed.hpp(253,17): message : This diagnostic occurred in the compiler generated function 'auto std::experimental::__p1673_version_0::linalg::impl::transposed_layout<std::experimental::layout_stride>::mapping(const std::experimental::layout_stride::mapping<Extents> &)'
It identifies lines 253 and 255 in transposed.hpp; lines 252-255 are as follows:
template<class OriginalExtents>
static auto mapping(const typename layout_stride::template mapping<OriginalExtents>& orig_map) {
using original_mapping_type = typename layout_stride::template mapping<OriginalExtents>;
using extents_type = transpose_extents_t<typename original_mapping_type::extents_type>;
I tried inserting the "ugly hack" referenced in Issue #242, but this did not fix the problem, even though it seemed it might be related.
If I comment out #include <experimental/linalg>, however, the project builds successfully.
Furthermore, if I restore the file so that the linalg file is included again, and I change the compiler Platform Toolset to the LLVM setting:
the code will compile successfully.
One final remark is that the exact same behavior is seen after changing the C++ Language Standard setting to C++20:
