Simple instructions to build and run a trivial auto differentiation example? about enoki

[erwincoumansepic]

Ah, enabling ENOKY_AUTODIFF option together with ENOKI_TEST produces some examples.
Using Visual Studio 2019 the autodiff examples creates an error:
This was using either ISO C++17 Standard (/std:c++17) and ISO C++17 Standard (/std:c++14) option. I suppose Visual Studio is not supported?

1>------ Build started: Project: enoki-autodiff, Configuration: Debug x64 ------
1>autodiff.cpp
1>D:\dev\enoki\include\enoki/autodiff.h(186,1): error C3546:  '...': there are no parameter packs available to expand
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1114): message :  see reference to class template instantiation 'enoki::DiffArray<Value>' being compiled
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1114): message :         with
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1114): message :         [
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1114): message :             Value=float
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1114): message :         ]
1>D:\dev\enoki\include\enoki/autodiff.h(126,1): error C3210:  'ArrayBase<float,enoki::DiffArray<float> >': a member using-declaration can only be applied to a base class member
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1120): message :  see reference to class template instantiation 'enoki::DiffArray<Value>' being compiled
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1120): message :         with
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1120): message :         [
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1120): message :             Value=enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1120): message :         ]
1>D:\dev\enoki\include\enoki/autodiff.h(126,1): error C3210:  'ArrayBase<double,enoki::DiffArray<double> >': a member using-declaration can only be applied to a base class member
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1123): message :  see reference to class template instantiation 'enoki::DiffArray<Value>' being compiled
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1123): message :         with
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1123): message :         [
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1123): message :             Value=enoki::DynamicArray<enoki::Packet<double,4,true,enoki::RoundingMode::Default>>
1>D:\dev\enoki\src\autodiff\autodiff.cpp(1123): message :         ]
1>Done building project "enoki-autodiff.vcxproj" -- FAILED.
2>------ Build started: Project: autodiff_native, Configuration: Debug x64 ------
2>autodiff.cpp
2>D:\dev\enoki\include\enoki/autodiff.h(1435,34): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1435,52): error C2906:  'enoki::Tape<float>': explicit specialization requires 'template <>'
2>D:\dev\enoki\include\enoki/autodiff.h(1436,34): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1436,57): error C2906:  'enoki::DiffArray<float>': explicit specialization requires 'template <>'
2>D:\dev\enoki\include\enoki/autodiff.h(1438,34): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1438,53): error C2906:  'enoki::Tape<double>': explicit specialization requires 'template <>'
2>D:\dev\enoki\include\enoki/autodiff.h(1439,34): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1439,58): error C2906:  'enoki::DiffArray<double>': explicit specialization requires 'template <>'
2>D:\dev\enoki\include\enoki/autodiff.h(1442,38): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1442,78): error C2906:  'enoki::Tape<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>': explicit specialization requires 'template <>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,38): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,83): error C2906:  'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>': explicit specialization requires 'template <>'
2>D:\dev\enoki\include\enoki/autodiff.h(1445,38): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1445,79): error C2906:  'enoki::Tape<enoki::DynamicArray<enoki::Packet<double,4,true,enoki::RoundingMode::Default>>>': explicit specialization requires 'template <>'
2>D:\dev\enoki\include\enoki/autodiff.h(1446,38): error C2059:  syntax error: 'template'
2>D:\dev\enoki\include\enoki/autodiff.h(1446,84): error C2906:  'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<double,4,true,enoki::RoundingMode::Default>>>': explicit specialization requires 'template <>'
2>D:\dev\enoki\tests\autodiff.cpp(50,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(50,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\include\enoki/array_router.h(711,37): error C2039:  'gradient': is not a member of 'enoki::struct_support<int,int>'
2>D:\dev\enoki\include\enoki\array_traits.h(521): message :  see declaration of 'enoki::struct_support<int,int>'
2>D:\dev\enoki\tests\autodiff.cpp(53): message :  see reference to function template instantiation 'decltype(auto) enoki::gradient<int&>(T)' being compiled
2>D:\dev\enoki\tests\autodiff.cpp(53): message :         with
2>D:\dev\enoki\tests\autodiff.cpp(53): message :         [
2>D:\dev\enoki\tests\autodiff.cpp(53): message :             T=int &
2>D:\dev\enoki\tests\autodiff.cpp(53): message :         ]
2>D:\dev\enoki\include\enoki\array_traits.h(151,1): error C3779:  'enoki::gradient': a function that returns 'decltype(auto)' cannot be used before it is defined
2>D:\dev\enoki\include\enoki/array_router.h(702): message :  see declaration of 'enoki::gradient'
2>D:\dev\enoki\tests\autodiff.cpp(53,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(57,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(57,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(60,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(64,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(64,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(64,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(64,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(67,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(69,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(70,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(74,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(74,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(74,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(74,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(77,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(79,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(83,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(83,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(83,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(83,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(86,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(88,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(89,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(93,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(93,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(93,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(93,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(96,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(98,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(100,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(104,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(104,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(104,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(104,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(107,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(109,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(110,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(114,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(114,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(114,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(114,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(117,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(119,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(121,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(125,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(125,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(125,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(125,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(128,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(130,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(131,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(135,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(135,14): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(135,25): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(135,23): warning C4244:  'initializing': conversion from 'float' to 'int', possible loss of data
2>D:\dev\enoki\tests\autodiff.cpp(138,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(140,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(142,5): error C2109:  subscript requires array or pointer type
2>D:\dev\enoki\tests\autodiff.cpp(146,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(146,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(146,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(146,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(146,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(146,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(146,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(148,16): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(150,5): error C2672:  'enoki::allclose': no matching overloaded function found
2>D:\dev\enoki\include\enoki\array_traits.h(415,1): error C2186:  '+': illegal operand of type 'void'
2>D:\dev\enoki\include\enoki\array_traits.h(428): message :  see reference to class template instantiation 'enoki::detail::expr_n<void,T1,T2>' being compiled
2>D:\dev\enoki\include\enoki\array_traits.h(428): message :         with
2>D:\dev\enoki\include\enoki\array_traits.h(428): message :         [
2>D:\dev\enoki\include\enoki\array_traits.h(428): message :             T1=void,
2>D:\dev\enoki\include\enoki\array_traits.h(428): message :             T2=float
2>D:\dev\enoki\include\enoki\array_traits.h(428): message :         ]
2>D:\dev\enoki\include\enoki/array_router.h(1279): message :  see reference to class template instantiation 'enoki::detail::expr<T1,T2>' being compiled
2>D:\dev\enoki\include\enoki/array_router.h(1279): message :         with
2>D:\dev\enoki\include\enoki/array_router.h(1279): message :         [
2>D:\dev\enoki\include\enoki/array_router.h(1279): message :             T1=void,
2>D:\dev\enoki\include\enoki/array_router.h(1279): message :             T2=float
2>D:\dev\enoki\include\enoki/array_router.h(1279): message :         ]
2>D:\dev\enoki\include\enoki/array_router.h(1279): message :  see reference to alias template instantiation 'enoki::expr_t<void,float>' being compiled
2>D:\dev\enoki\tests\autodiff.cpp(151,5): error C2672:  'enoki::allclose': no matching overloaded function found
2>D:\dev\enoki\tests\autodiff.cpp(151,5): error C2783:  'bool enoki::allclose(const T1 &,const T2 &,double,double)': could not deduce template argument for 'Value'
2>D:\dev\enoki\include\enoki/array_router.h(1280): message :  see declaration of 'enoki::allclose'
2>D:\dev\enoki\tests\autodiff.cpp(155,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(155,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(155,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(155,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(155,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(155,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(155,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(157,16): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(159,5): error C2672:  'enoki::allclose': no matching overloaded function found
2>D:\dev\enoki\tests\autodiff.cpp(160,5): error C2672:  'enoki::allclose': no matching overloaded function found
2>D:\dev\enoki\tests\autodiff.cpp(160,5): error C2783:  'bool enoki::allclose(const T1 &,const T2 &,double,double)': could not deduce template argument for 'Value'
2>D:\dev\enoki\include\enoki/array_router.h(1280): message :  see declaration of 'enoki::allclose'
2>D:\dev\enoki\tests\autodiff.cpp(164,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(164,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(164,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(164,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(164,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(164,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(164,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(166,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(168,5): error C2120:  'void' illegal with all types
2>D:\dev\enoki\tests\autodiff.cpp(172,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(172,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(172,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(172,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(172,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(172,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(172,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(174,16): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(176,5): error C2672:  'enoki::allclose': no matching overloaded function found
2>D:\dev\enoki\tests\autodiff.cpp(176,5): error C2783:  'bool enoki::allclose(const T1 &,const T2 &,double,double)': could not deduce template argument for 'Value'
2>D:\dev\enoki\include\enoki/array_router.h(1280): message :  see declaration of 'enoki::allclose'
2>D:\dev\enoki\tests\autodiff.cpp(180,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(180,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(180,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(180,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(180,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(180,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(180,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(182,16): error C2079:  'z' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(185,1): error C2672:  'allclose': no matching overloaded function found
2>D:\dev\enoki\include\enoki/array_generic.h(21,1): error C2783:  'bool enoki::allclose(const T1 &,const T2 &,double,double)': could not deduce template argument for 'Value'
2>D:\dev\enoki\include\enoki/array_router.h(1280): message :  see declaration of 'enoki::allclose'
2>D:\dev\enoki\tests\autodiff.cpp(190,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(190,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(190,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(190,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(190,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(190,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(190,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(192,16): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(194,5): error C2672:  'enoki::allclose': no matching overloaded function found
2>D:\dev\enoki\tests\autodiff.cpp(194,5): error C2783:  'bool enoki::allclose(const T1 &,const T2 &,double,double)': could not deduce template argument for 'Value'
2>D:\dev\enoki\include\enoki/array_router.h(1280): message :  see declaration of 'enoki::allclose'
2>D:\dev\enoki\tests\autodiff.cpp(198,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(198,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(198,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(198,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(198,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(198,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(198,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(200,16): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(202,1): error C2672:  'enoki::allclose': no matching overloaded function found
2>D:\dev\enoki\tests\autodiff.cpp(203,1): error C2783:  'bool enoki::allclose(const T1 &,const T2 &,double,double)': could not deduce template argument for 'Value'
2>D:\dev\enoki\include\enoki/array_router.h(1280): message :  see declaration of 'enoki::allclose'
2>D:\dev\enoki\tests\autodiff.cpp(207,16): error C2079:  'x' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(207,45): error C2664:  'Arg enoki::linspace<FloatD,0>(enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>,size_t)': cannot convert argument 1 from 'float' to 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(207,45): error C2664:         with
2>D:\dev\enoki\tests\autodiff.cpp(207,45): error C2664:         [
2>D:\dev\enoki\tests\autodiff.cpp(207,45): error C2664:             Arg=FloatD
2>D:\dev\enoki\tests\autodiff.cpp(207,45): error C2664:         ]
2>D:\dev\enoki\tests\autodiff.cpp(207,45): message :  use of undefined type 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\include\enoki/autodiff.h(1443,45): message :  see declaration of 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(209,16): error C2079:  'y' uses undefined struct 'enoki::DiffArray<enoki::DynamicArray<enoki::Packet<float,8,true,enoki::RoundingMode::Default>>>'
2>D:\dev\enoki\tests\autodiff.cpp(209,16): error C1003:  error count exceeds 100; stopping compilation
2>Done building project "autodiff_native.vcxproj" -- FAILED.
========== Build: 0 succeeded, 2 failed, 1 up-to-date, 0 skipped ==========

[wjakob]

The library is generally a header file library (so no cmake-related explanation needed) except for the autodiff portions that you mention. These are currently only supported on Linux in conjunction with the CUDA backend. Probably it's not too hard to support other combinations with autodiff, but this is what it is at least for now.

[eliemichel]

@wjakob What are the plans regarding other plateform's support for autodiff? Is it far from it or is it more the matter of minor changes? In the latter case, could you point me to the core reason of current non-portability? I could give it a shot.

edit: As of June 2020, autodiff works on Windows, despite some minor issues.

[erwincoumans]

Still getting those errors using Visual Studio 2019

enoki\include\enoki/dynamic.h(1134,34): error C2059: syntax error: 'template'
'enoki::Tape<float>': explicit specialization requires 'template <>'

@eliemichel how did you get around those?