C++17 Support

[codecircuit]

I tried to use cuda-kat with c++17, which fails to compile. The reproduction should be easy, because already the include of the header causes compilation issues.

[eyalroz]

And does it compile ok with CUDA 11 but C++14? C++11?

[codecircuit]

With C++14 it works fine.

[eyalroz]

Which version of CUDA are you using?

When using CUDA 11.0.3, I get compilation errors with C++11 (or 14) as well, see:

https://stackoverflow.com/questions/64968200/constexpr-note-invalid-arithmetic-on-non-array-pointer

Can you describe what you're seeing more specifically, with relevant version numbers and error messages?

[eyalroz]

... well, I've started working on C++17 compatibility with CUDA 11.1. Definitely a bunch of issues - but all minor so far.

[codecircuit]

CMakeLists.txt:

cmake_minimum_required(VERSION 3.18)

project(foobarbaz LANGUAGES CXX CUDA)

find_package(cuda-kat REQUIRED)

add_executable(foobarbaz "foobarbaz.cu")

target_link_libraries(
    foobarbaz
    PRIVATE
    cuda-kat::cuda-kat
)

target_compile_features(foobarbaz PUBLIC cuda_std_17)

My source code file foobarbaz.cu:

#include <kat/containers/array.hpp>

__global__ void kernel(kat::array<kat::array<int*, 5>, 4> arr) {
    *arr[threadIdx.x][threadIdx.x] = threadIdx.x;
}

int main() {}

I use CMake 3.18.4, CUDA 11.1.105, and GCC 8.32 and built the project with the Release build. The compile error I get:

/home/wolf/repositories/cuda-kat/src/kat/common.hpp(49): error: constant "B" is not a type name

/home/wolf/repositories/cuda-kat/src/kat/detail/range_access.hpp(283): error: "empty" has already been declared in the current scope

/home/wolf/repositories/cuda-kat/src/kat/detail/range_access.hpp(283): error: identifier "initializer_list" is undefined

/home/wolf/repositories/cuda-kat/src/kat/detail/range_access.hpp(283): error: type name is not allowed

/home/wolf/repositories/cuda-kat/src/kat/detail/range_access.hpp(283): error: identifier "init_list" is undefined

/home/wolf/repositories/cuda-kat/src/kat/detail/range_access.hpp(283): error: expected a ";"

/usr/include/wchar.h(284): error: identifier "wint_t" is undefined

/usr/include/wchar.h(288): error: identifier "wint_t" is undefined

/usr/include/wchar.h(316): error: identifier "wint_t" is undefined

/usr/include/wchar.h(318): error: expected a ";"

/usr/include/wchar.h(324): error: declaration is incompatible with "int kat::wctob(<error-type>) throw()"
(288): here

...

To compile it again I applied this hack:

diff --git a/src/kat/common.hpp b/src/kat/common.hpp
index 0c6c6e2..0d6c770 100644
--- a/src/kat/common.hpp
+++ b/src/kat/common.hpp
@@ -25,8 +25,8 @@ namespace kat {
  */
 using size_t = std::size_t;

-#if __cplusplus < 201703L
-
+//#if __cplusplus < 201703L
+#if 1
 // Some C++17 type traits definable in C++11

 template<typename ...               > struct conjunction : std::true_type {};
diff --git a/src/kat/detail/range_access.hpp b/src/kat/detail/range_access.hpp
index b2b9aa9..54a0d6f 100644
--- a/src/kat/detail/range_access.hpp
+++ b/src/kat/detail/range_access.hpp
@@ -278,10 +278,10 @@ namespace kat {
    *  @brief  Return whether an initializer_list is empty.
    *  @param  init_list  Initializer list.
    */
-  template <typename T>
-    [[nodiscard]] constexpr bool
-    empty(initializer_list<T> init_list) noexcept
-    { return init_list.size() == 0;}
+  // template <typename T>
+  //   [[nodiscard]] constexpr bool
+  //   empty(initializer_list<T> init_list) noexcept
+  //   { return init_list.size() == 0;}

   /**
    *  @brief  Return the data pointer of a container.
@@ -316,10 +316,10 @@ namespace kat {
    *  @brief  Return the data pointer of an initializer list.
    *  @param  init_list  Initializer list.
    */
-  template <typename T>
-    constexpr const T*
-    data(initializer_list<T> init_list) noexcept
-    { return init_list.begin(); }
+  // template <typename T>
+  //   constexpr const T*
+  //   data(initializer_list<T> init_list) noexcept
+  //   { return init_list.begin(); }

 #endif // C++17

[eyalroz]

Try it now.

[codecircuit]

It works now. Thanks!