VS: 17.1.2 MSVC: 19.31.31105

Missing header <array>

(E2500 is a false positive error from the editor, it doesn't affect the compiler)

Fix:

#include <array>

Missing appropriate constructor for msvc_c7599_false_positive_workaround

1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\xmemory(676,18): error C2672: 'std::construct_at': no matching overloaded function found
1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\vector(602): message : see reference to function template instantiation 'void std::_Default_allocator_traits<_Alloc>::construct<_Ty,std::thread,std::span<const std::byte,18446744073709551615>>(_Alloc &,_Objty *const ,std::thread &&,std::span<const std::byte,18446744073709551615> &&)' being compiled
1>        with
1>        [
1>            _Alloc=std::allocator<sigmatch::multi_threaded_searcher::thread_info>,
1>            _Ty=sigmatch::multi_threaded_searcher::thread_info,
1>            _Objty=sigmatch::multi_threaded_searcher::thread_info
1>        ]
1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\vector(607): message : see reference to function template instantiation 'void std::_Default_allocator_traits<_Alloc>::construct<_Ty,std::thread,std::span<const std::byte,18446744073709551615>>(_Alloc &,_Objty *const ,std::thread &&,std::span<const std::byte,18446744073709551615> &&)' being compiled
1>        with
1>        [
1>            _Alloc=std::allocator<sigmatch::multi_threaded_searcher::thread_info>,
1>            _Ty=sigmatch::multi_threaded_searcher::thread_info,
1>            _Objty=sigmatch::multi_threaded_searcher::thread_info
1>        ]
1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\vector(620): message : see reference to function template instantiation '_Ty &std::vector<_Ty,std::allocator<_Ty>>::_Emplace_back_with_unused_capacity<std::thread,std::span<const std::byte,18446744073709551615>>(std::thread &&,std::span<const std::byte,18446744073709551615> &&)' being compiled
1>        with
1>        [
1>            _Ty=sigmatch::multi_threaded_searcher::thread_info
1>        ]
1>C:\sigmatch\include\sigmatch/sigmatch.hpp(2159): message : see reference to function template instantiation '_Ty &std::vector<_Ty,std::allocator<_Ty>>::emplace_back<std::thread,std::span<const std::byte,18446744073709551615>>(std::thread &&,std::span<const std::byte,18446744073709551615> &&)' being compiled
1>        with
1>        [
1>            _Ty=sigmatch::multi_threaded_searcher::thread_info
1>        ]
1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\xmemory(676,18): error C2783: '_Ty *std::construct_at(_Ty *const ,_Types &&...) noexcept(<expr>)': could not deduce template argument for '<unnamed-symbol>'
1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\xutility(134): message : see declaration of 'std::construct_at'
1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\xmemory(680,47): error C2440: 'initializing': cannot convert from 'initializer list' to 'sigmatch::multi_threaded_searcher::thread_info'
1>C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\xmemory(680,47): message : Invalid aggregate initialization

Test code:

1>C:\sigmatch\include\sigmatch/sigmatch.hpp(2165,1): error C2665: 'sigmatch::impl::msvc_c7599_false_positive_workaround::msvc_c7599_false_positive_workaround': none of the 3 overloads could convert all the argument types
1>C:\sigmatch\include\sigmatch/sigmatch.hpp(955,1): message : could be 'sigmatch::impl::msvc_c7599_false_positive_workaround::msvc_c7599_false_positive_workaround(sigmatch::impl::msvc_c7599_false_positive_workaround &&)'
1>C:\sigmatch\include\sigmatch/sigmatch.hpp(955,1): message : or       'sigmatch::impl::msvc_c7599_false_positive_workaround::msvc_c7599_false_positive_workaround(const sigmatch::impl::msvc_c7599_false_positive_workaround &)'
1>C:\sigmatch\include\sigmatch/sigmatch.hpp(955,1): message : or       'sigmatch::impl::msvc_c7599_false_positive_workaround::msvc_c7599_false_positive_workaround(void)'
1>C:\sigmatch\include\sigmatch/sigmatch.hpp(2165,1): message : or       'sigmatch::impl::msvc_c7599_false_positive_workaround::msvc_c7599_false_positive_workaround<const std::byte,18446744073709551615>(const std::span<const std::byte,18446744073709551615> &)', which inherits 'std::span<const std::byte,18446744073709551615>::span(const std::span<_OtherTy,_OtherExtent> &) noexcept' via base class 'std::span<const std::byte,18446744073709551615>'
1>C:\sigmatch\include\sigmatch/sigmatch.hpp(2165,1): message : while trying to match the argument list '(std::span<const std::byte,18446744073709551615>)'

I'm not sure whether this is a bug of MSVC, but there is no harm to add a constructor to fix it:

class msvc_c7599_false_positive_workaround : public std::span<const std::byte>
{
public:
    using std::span<const std::byte>::span;
    
    msvc_c7599_false_positive_workaround(const std::span<const std::byte>& span) : std::span<const std::byte>(span) {}
};