Fix static assertion failures on Windows MSVC tool chain detected by cppget.org CI

[cdeln]

[cdeln]

See this ci request: https://ci.cppget.org/@e83bbab2-5067-4db6-b13b-5648da88d3f9 .
It's probably due to bugs in the MSVC compiler, I can't reproduce it on my machine with a more recent compiler.
I am using compiler version Microsoft (R) C/C++ Optimizing Compiler Version 19.29.30038.1 for x64, located at C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Tools\MSVC\14.29.30037\bin\Hostx86\x64\cl.exe .
If you can reproduce the errors on https://ci.cppget.org/@e83bbab2-5067-4db6-b13b-5648da88d3f9 , then please grab this issue and fix it.