[Build] Float16_t and BFloat16_t compile error

[cr-galrosen]

Describe the issue

I'm building my project in VS 2017, and getting the compiler error C3615.
Only by removing the constexpr from the constructor and static function, the build succeed.
I am using version 1.17.3.

Urgency

No response

Target platform

Windows

Build script

/permissive- /Yu"pch.h" /MP /GS /GL /W3 /Gy /Zc:wchar_t /Qspectre /Zi /Gm- /O2 /sdl /Fd /Zc:inline /fp:precise /D "SQLITE_HAS_CODEC" /D "BOOST_USE_STATIC_LIBS" /D "NOMINMAX" /D "WIN32" /D "BOOST_SIGNALS_NO_DEPRECATION_WARNING" /D "ONNXRUNTIME_DYN_LINK" /D "NNG_SHARED_LIB" /D "GTEST_LANG_CXX11=1" /D "GTEST_HAS_TR1_TUPLE=0" /D "BOOST_ALL_NO_LIB" /D "_UNICODE" /D "UNICODE" /errorReport:prompt /WX /Zc:forScope /Gd /Oi /MD /FC /Fa /EHsc /nologo /Fo /Fp /diagnostics:classic

Error / output

1>c:.conan\cee678\1\include\onnxruntime_cxx_api.h(171): error C3615: constexpr function 'Ort::Float16_t::Float16_t' cannot result in a constant expression (compiling source file ***.cpp)
1>c:.conan\cee678\1\include\onnxruntime_cxx_api.h(171): note: failure was caused by call of undefined function or one not declared 'constexpr' (compiling source file ***.cpp)
1>c:.conan\cee678\1\include\onnxruntime_cxx_api.h(171): note: see usage of 'onnxruntime_float16::Float16ImplOrt::Float16_t::Float16Impl' (compiling source file ***.cpp)
1>c:.conan\cee678\1\include\onnxruntime_cxx_api.h(171): error C3615: constexpr function 'Ort::Float16_t::Float16_t' cannot result in a constant expression (compiling source file ***.cpp)
1>c:.conan\cee678\1\include\onnxruntime_cxx_api.h(171): note: failure was caused by call of undefined function or one not declared 'constexpr' (compiling source file ***.cpp)
1>c:.conan\cee678\1\include\onnxruntime_cxx_api.h(171): note: see usage of 'onnxruntime_float16::Float16ImplOrt::Float16_t::Float16Impl' (compiling source file ***.cpp)

Visual Studio Version

C:\Program Files (x86)\Microsoft Visual Studio\2019\Professional>cl
Microsoft (R) C/C++ Optimizing Compiler Version 19.29.30154 for x64

GCC / Compiler Version

We build the onnxruntime library with the following conan profile:
[settings]
os=Windows
os_build=Windows
arch=x86_64
arch_build=x86_64
compiler=Visual Studio
compiler.version=16
build_type=Release

[cr-galrosen]

@snnn @yuslepukhin can you please advise?

[Changming Sun]

Please use the VS 2022 instead.

[cr-galrosen]

@snnn, I tried o build both the onnxruntime library and my application with VS 2022 and I get the same error.