backport to_underlying (#2853)

* backport `to_underlying` to C++11 * disable test on bit field enums for pre gcc 9.3 due to unmuteable warnings
NVIDIA · Nov 19, 2024 · c5573f1 · c5573f1
1 parent f9d56e5
commit c5573f1
Show file tree

Hide file tree

Showing 5 changed files with 21 additions and 21 deletions.
diff --git a/c2h/include/c2h/catch2_test_helper.h b/c2h/include/c2h/catch2_test_helper.h
@@ -221,7 +221,7 @@ struct Catch::StringMaker<cudaError>
 {
   static auto convert(cudaError e) -> std::string
   {
-    return std::to_string(cuda::std::__to_underlying(e)) + " (" + cudaGetErrorString(e) + ")";
+    return std::to_string(cuda::std::to_underlying(e)) + " (" + cudaGetErrorString(e) + ")";
   }
 };
 

diff --git a/libcudacxx/include/cuda/std/__utility/to_underlying.h b/libcudacxx/include/cuda/std/__utility/to_underlying.h
@@ -25,19 +25,11 @@
 
 _LIBCUDACXX_BEGIN_NAMESPACE_STD
 
-template <class _Tp>
-_LIBCUDACXX_HIDE_FROM_ABI constexpr typename underlying_type<_Tp>::type __to_underlying(_Tp __val) noexcept
-{
-  return static_cast<typename underlying_type<_Tp>::type>(__val);
-}
-
-#if _CCCL_STD_VER > 2020
 template <class _Tp>
 _CCCL_NODISCARD _LIBCUDACXX_HIDE_FROM_ABI constexpr underlying_type_t<_Tp> to_underlying(_Tp __val) noexcept
 {
-  return _CUDA_VSTD::__to_underlying(__val);
+  return static_cast<underlying_type_t<_Tp>>(__val);
 }
-#endif
 
 _LIBCUDACXX_END_NAMESPACE_STD
 

diff --git a/libcudacxx/include/cuda/std/version b/libcudacxx/include/cuda/std/version
@@ -29,6 +29,8 @@
 #  include <ciso646> // otherwise go for the smallest possible header
 #endif // !_CCCL_COMPILER(NVRTC)
 
+#define __cccl_lib_to_underlying 202102L
+
 #if _CCCL_STD_VER >= 2014
 #  define __cccl_lib_bit_cast     201806L
 #  define __cccl_lib_chrono_udls  201304L
@@ -244,8 +246,7 @@
 // # define __cccl_lib_stdatomic_h                          202011L
 // # define __cccl_lib_string_contains                      202011L
 // # define __cccl_lib_string_resize_and_overwrite          202110L
-#  define __cccl_lib_to_underlying 202102L
-#  define __cccl_lib_unreachable   202202L
+#  define __cccl_lib_unreachable 202202L
 
 #endif // _CCCL_STD_VER >= 2023
 

diff --git a/libcudacxx/test/libcudacxx/std/utilities/utility/utility.underlying/to_underlying.pass.cpp b/libcudacxx/test/libcudacxx/std/utilities/utility/utility.underlying/to_underlying.pass.cpp
@@ -7,11 +7,9 @@
 //
 //===----------------------------------------------------------------------===//
 
-// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
-
 // [utility.underlying], to_underlying
 // template <class T>
-//     constexpr underlying_type_t<T> to_underlying( T value ) noexcept; // C++2b
+//     constexpr underlying_type_t<T> to_underlying( T value ) noexcept;
 
 #include <cuda/std/cassert>
 #include <cuda/std/cstdint>
@@ -20,6 +18,10 @@
 
 #include "test_macros.h"
 
+#if defined(TEST_COMPILER_GCC) && ((TEST_GCC_VER >= 900 && TEST_GCC_VER < 903) || TEST_GCC_VER < 804)
+#  define OMIT_BITFIELD_ENUMS 1
+#endif
+
 enum class e_default
 {
   a = 0,
@@ -54,14 +56,16 @@ enum class e_bool : cuda::std::uint8_t
   t = 1
 };
 
+#if !OMIT_BITFIELD_ENUMS
 struct WithBitfieldEnums
 {
   e_default e1 : 3;
   e_ushort e2  : 6;
   e_bool e3    : 1;
 };
+#endif // !OMIT_BITFIELD_ENUMS
 
-__host__ __device__ constexpr bool test()
+__host__ __device__ TEST_CONSTEXPR_CXX14 bool test()
 {
   ASSERT_NOEXCEPT(cuda::std::to_underlying(e_default::a));
   ASSERT_SAME_TYPE(int, decltype(cuda::std::to_underlying(e_default::a)));
@@ -88,21 +92,26 @@ __host__ __device__ constexpr bool test()
   assert(cuda::std::numeric_limits<int>::min() == cuda::std::to_underlying(enum_min));
   assert(cuda::std::numeric_limits<int>::max() == cuda::std::to_underlying(enum_max));
 
-  WithBitfieldEnums bf;
+#if !OMIT_BITFIELD_ENUMS
+  WithBitfieldEnums bf{};
   bf.e1 = static_cast<e_default>(3);
   bf.e2 = e_ushort::e;
   bf.e3 = e_bool::t;
   assert(3 == cuda::std::to_underlying(bf.e1));
   assert(25 == cuda::std::to_underlying(bf.e2));
   assert(1 == cuda::std::to_underlying(bf.e3));
+#endif // !OMIT_BITFIELD_ENUMS
 
   return true;
 }
 
 int main(int, char**)
 {
   test();
-  static_assert(test());
+
+#if TEST_STD_VER >= 2014
+  static_assert(test(), "");
+#endif // TEST_STD_VER >= 2014
 
   return 0;
 }
diff --git a/libcudacxx/test/libcudacxx/std/utilities/utility/utility.underlying/to_underlying.verify.cpp b/libcudacxx/test/libcudacxx/std/utilities/utility/utility.underlying/to_underlying.verify.cpp
@@ -7,11 +7,9 @@
 //
 //===----------------------------------------------------------------------===//
 
-// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
-
 // [utility.underlying], to_underlying
 // template <class T>
-//     constexpr underlying_type_t<T> to_underlying( T value ) noexcept; // C++2b
+//     constexpr underlying_type_t<T> to_underlying( T value ) noexcept;
 
 #include <cuda/std/utility>