Failure to expand certain multi-line macros properly

[devshgraphicsprogramming]

Hi, I have the following piece of code

#define alignof(expr) ::nbl::hlsl::alignment_of<__decltype(expr)>::value

// shoudl really return a std::type_info like struct or something, but no `constexpr` and unsure whether its possible to have a `const static SomeStruct` makes it hard to do...
#define typeid(expr) (::nbl::hlsl::impl::typeid_t<__decltype(expr)>::value)

#define NBL_REGISTER_OBJ_TYPE(T, A) namespace nbl { namespace hlsl { \
    namespace impl { template<> struct typeid_t<T> : integral_constant<uint32_t,__COUNTER__> {}; } \ 
    template<> struct alignment_of<T> : integral_constant<uint32_t,A> {}; \
    template<> struct alignment_of<const T> : integral_constant<uint32_t,A> {}; \
    template<> struct alignment_of<typename impl::add_lvalue_reference<T>::type> : integral_constant<uint32_t,A> {}; \
    template<> struct alignment_of<typename impl::add_lvalue_reference<const T>::type> : integral_constant<uint32_t,A> {}; \
}}

// TODO: find out how to do it such that we don't get duplicate definition if we use two function identifiers with same signature
#define NBL_REGISTER_FUN_TYPE(fn) namespace nbl { namespace hlsl { template<> struct typeid_t<__decltype(fn)> : integral_constant<uint32_t,__COUNTER__> {}; }}
// TODO: ideally we'd like to call NBL_REGISTER_FUN_TYPE under the hood, but we can't right now. Also we have a bigger problem, the passing of the function identifier as the second template parameter doesn't work :(
/*
template<> \
struct function_info<__decltype(fn),fn> \
{ \
    using type = __decltype(fn); \
    static const uint32_t address = __COUNTER__; \
}; \
}}}}
*/

// builtins

#define NBL_REGISTER_MATRICES(T, A) \
    NBL_REGISTER_OBJ_TYPE(T, A) \
    NBL_REGISTER_OBJ_TYPE(T ## x4, A) \
    NBL_REGISTER_OBJ_TYPE(T ## x3, A) \
    NBL_REGISTER_OBJ_TYPE(T ## x2, A) \

#define NBL_REGISTER_TYPES_FOR_SCALAR(T) \
    NBL_REGISTER_OBJ_TYPE(T, sizeof(T)) \
    NBL_REGISTER_OBJ_TYPE(T ## 1, sizeof(T)) \
    NBL_REGISTER_MATRICES(T ## 2, sizeof(T)) \
    NBL_REGISTER_MATRICES(T ## 3, sizeof(T)) \
    NBL_REGISTER_MATRICES(T ## 4, sizeof(T))

NBL_REGISTER_TYPES_FOR_SCALAR(int16_t)
NBL_REGISTER_TYPES_FOR_SCALAR(int32_t)
NBL_REGISTER_TYPES_FOR_SCALAR(int64_t)

NBL_REGISTER_TYPES_FOR_SCALAR(uint16_t)
NBL_REGISTER_TYPES_FOR_SCALAR(uint32_t)
NBL_REGISTER_TYPES_FOR_SCALAR(uint64_t)

NBL_REGISTER_TYPES_FOR_SCALAR(bool)

NBL_REGISTER_TYPES_FOR_SCALAR(float16_t)
NBL_REGISTER_TYPES_FOR_SCALAR(float32_t)
NBL_REGISTER_TYPES_FOR_SCALAR(float64_t)

#undef NBL_REGISTER_MATRICES
#undef NBL_REGISTER_TYPES_FOR_SCALAR

Wave leaves a piece of NBL_REGISTER_OBJ_TYPE behind.

The output should be: good.txt

I got this instead: bad.txt

Changing the definition of NBL_REGISTER_OBJ_TYPE to:

#define NBL_IMPL_SPECIALIZE_TYPE_ID(T) namespace impl { template<> struct typeid_t<T> : integral_constant<uint32_t,__COUNTER__> {}; }

#define NBL_REGISTER_OBJ_TYPE(T,A) namespace nbl { namespace hlsl { NBL_IMPL_SPECIALIZE_TYPE_ID(T) \
    template<> struct alignment_of<T> : integral_constant<uint32_t,A> {}; \
    template<> struct alignment_of<const T> : integral_constant<uint32_t,A> {}; \
    template<> struct alignment_of<typename impl::add_lvalue_reference<T>::type> : integral_constant<uint32_t,A> {}; \
    template<> struct alignment_of<typename impl::add_lvalue_reference<const T>::type> : integral_constant<uint32_t,A> {}; \
}}

fixes the problem

[jefftrull]

Thanks for the bug report! That's quite a diff :) Any chance of a more minimal repro?

[devshgraphicsprogramming]

Thanks for the bug report! That's quite a diff :) Any chance of a more minimal repro?

its quite hard to provoke it, but I guess you could try with

#define alignof(expr) ::nbl::hlsl::alignment_of<__decltype(expr)>::value

// shoudl really return a std::type_info like struct or something, but no `constexpr` and unsure whether its possible to have a `const static SomeStruct` makes it hard to do...
#define typeid(expr) (::nbl::hlsl::impl::typeid_t<__decltype(expr)>::value)

#define NBL_REGISTER_OBJ_TYPE(T, A) namespace nbl { namespace hlsl { \
    namespace impl { template<> struct typeid_t<T> : integral_constant<uint32_t,__COUNTER__> {}; } \ 
    template<> struct alignment_of<T> : integral_constant<uint32_t,A> {}; \
    template<> struct alignment_of<const T> : integral_constant<uint32_t,A> {}; \
}}

#define NBL_REGISTER_TYPES_FOR_SCALAR(T) \
    NBL_REGISTER_OBJ_TYPE(T, sizeof(T)) \
    NBL_REGISTER_OBJ_TYPE(T ## 1, sizeof(T)) \
    NBL_REGISTER_MATRICES(T ## 2, sizeof(T)) \
    NBL_REGISTER_MATRICES(T ## 3, sizeof(T)) \
    NBL_REGISTER_MATRICES(T ## 4, sizeof(T))

NBL_REGISTER_TYPES_FOR_SCALAR(int16_t)

This is all about the preprocessor loosing its marbles and leaving me a random

    template<> struct alignment_of<T> : integral_constant<uint32_t,A> {};     template<> struct alignment_of<const T> : integral_constant<uint32_t,A> {};     template<> struct alignment_of<typename impl::add_lvalue_reference<T>::type> : integral_constant<uint32_t,A> {};     template<> struct alignment_of<typename impl::add_lvalue_reference<const T>::type> : integral_constant<uint32_t,A> {}; }}

where the multiline macro definition used to be.

And then pasting \ in to the output whenever I use it

[jefftrull]

Thanks! And can you tell us how you ran this - did you use the "wave" tool? If so, what were the command line options? And if it's your own code using Wave as a library, can I get access to that?

[devshgraphicsprogramming]

Thanks! And can you tell us how you ran this - did you use the "wave" tool? If so, what were the command line options?

Unfortunately no, I guess I could have an intern try to reproduce through that.

The issue is that I needed to "hack" quite a lot to make Boost.Wave use my own virtual filesystem (to be able to include from archives etc that I have mounted) https://github.com/Devsh-Graphics-Programming/Nabla/blob/master/src/nbl/asset/utils/waveContext.h as the hooks, etc. were not flexible enough for that.

And if it's your own code using Wave as a library, can I get access to that?

yes sure, check out example 05 in https://github.com/Devsh-Graphics-Programming/Nabla (make sure you do a non-recursive clone, via ssh, and use our cmake infrastructure to build).

but undo the changes from this commit https://github.com/Devsh-Graphics-Programming/Nabla/commit/145fac521aba9c5f2d495be6aa29c457553f6d58

There's also another bug that newlines after #pragma were missing.

[jefftrull]

Re: the pragma newlines, we'd be very interested in seeing this bug. I wonder if #188 is related in any way - we made some changes for 1.84 there.

[jefftrull]

OK actually I was able to reproduce using the wave driver. Try this option, which lists the defined macros:

wave -m - your_filename_here.cpp

This shows that only the first line of the macro definition makes it through. But why is that? It turns out there is an extra space following the second backslash - the backslash escapes the space, not the following newline :) So to Wave this is a two line macro definition ending in an unnecessarily escaped space character.

Does fixing that resolve your issue?

[devshgraphicsprogramming]

Re: the pragma newlines, we'd be very interested in seeing this bug. I wonder if #188 is related in any way - we made some changes for 1.84 there.

it a different bug, instead of #pragma\n triggering a segfault, we have #pragma region SOMETHING\n being pasted into output without the terminating newline.

[devshgraphicsprogramming]

But why is that? It turns out there is an extra space following the second backslash - the backslash escapes the space, not the following newline :) So to Wave this is a two line macro definition ending in an unnecessarily escaped space character.

Does fixing that resolve your issue?

Are you saying its a "bug" or a "feature"?

Because I used to feed all these macros to Clang/DXC and the preprocessor there doesn't complain.

Also why were the / pasted whenever the macro got used?

[hkaiser]

But why is that? It turns out there is an extra space following the second backslash - the backslash escapes the space, not the following newline :) So to Wave this is a two line macro definition ending in an unnecessarily escaped space character.

Does fixing that resolve your issue?

Are you saying its a "bug" or a "feature"?

Because I used to feed all these macros to Clang/DXC and the preprocessor there doesn't complain.

Apparently this has been changed recently (after C++20). Before C++23, the standard mandated that a '\' was to be treated as an end-of-line continuation only if it is the last character on a line.

Now it says (https://eel.is/c++draft/lex.phases#1.2):

Each sequence of a backslash character ('\') immediately followed by zero or more whitespace characters other than new-line followed by a new-line character is deleted, splicing physical source lines to form logical source lines.

This needs fixing on our end requiring introducing a C++23 mode.

[jefftrull]

I'll add the C++23 behavior to our list - we have several such features to implement. @devshgraphicsprogramming would you be willing to file a bug on the pragma issue you are experiencing?

[jefftrull]

Re: the pasted \, as far as I can tell that happens only when the following character is a space. Is that incorrect? I'm not sure.

[devshgraphicsprogramming]

Re: the pasted \, as far as I can tell that happens only when the following character is a space. Is that incorrect? I'm not sure.

in bad.txt we have this:

namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int16_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \
namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int32_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \
namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<int64_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \

namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint16_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \
namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint32_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \
namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<uint64_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \

namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<bool4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \

namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float16_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \
namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float32_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \
namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t1> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t2x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t2x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t2x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t3x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t3x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t3x2> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t4x4> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t4x3> : integral_constant<uint32_t,__COUNTER__> {}; } \     namespace nbl { namespace hlsl {     namespace impl { template<> struct typeid_t<float64_t4x2> : integral_constant<uint32_t,__COUNTER__> {}; } \

whenever the macro was used, there was only one \ with a space after it.

[jefftrull]

That's right - the source of those \ characters is the same thing each time - the line with a trailing space, i.e.

namespace impl { template<> struct typeid_t<T> : integral_constant<uint32_t,__COUNTER__> {}; } \ <<<-- always this one

You shouldn't see them anymore if you remove the space. What I'm wondering is what the "correct" C++20 behavior is for this case.

[hkaiser]

That's right - the source of those \ characters is the same thing each time - the line with a trailing space, i.e.

namespace impl { template<> struct typeid_t<T> : integral_constant<uint32_t,__COUNTER__> {}; } \ <<<-- always this one

You shouldn't see them anymore if you remove the space. What I'm wondering is what the "correct" C++20 behavior is for this case.

C++20 still has the 'old' behavior (no whitespace allowed after the '\').

[jefftrull]

Since we have a feature request issue entered for this, and a workaround (removing the extra space), I think this should probably be closed. @devshgraphicsprogramming if you want to, please enter a separate issue for the pragma problem you brought up.