vtknlohman build error

I just downloaded 9.4.2 and trying to build with:

c++ --version

Apple clang version 17.0.0 (clang-1700.0.13.3)

Target: arm64-apple-darwin24.4.0

Thread model: posix

InstalledDir: /Library/Developer/CommandLineTools/usr/bin

I get this error:

/Users/dpn/proj/ct-scan/mb/mb/VTK-9.4.2/ThirdParty/nlohmannjson/vtknlohmannjson/include/vtknlohmann/detail/input/binary_reader.hpp:68:41: error: implicit instantiation of undefined template ‘std::char_traits’

68 | using char_int_type = typename std::char_traits<char_type>::int_type;

It fails if I disable this package.

The fix (https://gitlab.kitware.com/vtk/vtk/-/merge_requests/11873) is in master branch and will be available in 9.5.0 (coming out this month i believe)

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