Move cccl global logic into a __cccl_config

We just reused the libcu++ config, but going forward we want to move more common parts into a unified config.

cub/cub/config.cuh

@@ -33,7 +33,7 @@
 #pragma once
 
 // For `_CCCL_IMPLICIT_SYSTEM_HEADER`
-#include <cuda/std/detail/__config>
+#include <cuda/__cccl_config>
 
 _CCCL_IMPLICIT_SYSTEM_HEADER
 

cub/cub/detail/detect_cuda_runtime.cuh

@@ -34,7 +34,7 @@
 #pragma once
 
 // We cannot use `cub/config.cuh` here due to circular dependencies
-#include <cuda/std/detail/__config>
+#include <cuda/__cccl_config>
 
 _CCCL_IMPLICIT_SYSTEM_HEADER
 

cub/cub/util_compiler.cuh

@@ -33,7 +33,7 @@
 #pragma once
 
 // For `_CCCL_IMPLICIT_SYSTEM_HEADER`
-#include <cuda/std/detail/__config>
+#include <cuda/__cccl_config>
 
 _CCCL_IMPLICIT_SYSTEM_HEADER
 

cub/cub/util_cpp_dialect.cuh

@@ -31,7 +31,7 @@
 
 #pragma once
 
-#include <cuda/std/detail/__config>
+#include <cuda/__cccl_config>
 
 _CCCL_IMPLICIT_SYSTEM_HEADER
 

cub/cub/version.cuh

@@ -36,7 +36,7 @@
 #pragma once
 
 // For `_CCCL_IMPLICIT_SYSTEM_HEADER`
-#include <cuda/std/detail/__config>
+#include <cuda/__cccl_config>
 
 _CCCL_IMPLICIT_SYSTEM_HEADER
 

libcudacxx/include/cuda/__cccl_config

@@ -0,0 +1,16 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of libcu++, the C++ Standard Library for your entire system,
+// under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+// SPDX-FileCopyrightText: Copyright (c) 2023 NVIDIA CORPORATION & AFFILIATES.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _CUDA__CCCL_CONFIG
+#define _CUDA__CCCL_CONFIG
+
+#include "std/detail/libcxx/include/__cccl_config"
+
+#endif // _CUDA__CCCL_CONFIG

libcudacxx/include/cuda/std/detail/libcxx/include/CMakeLists.txt

@@ -6,6 +6,7 @@ set(files
   __bsd_locale_defaults.h
   __bsd_locale_fallbacks.h
   __errc
+  __cccl_config
   __concepts/__concept_macros.h
   __concepts/_One_of.h
   __concepts/arithmetic.h

libcudacxx/include/cuda/std/detail/libcxx/include/__cccl_config

@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of libcu++, the C++ Standard Library for your entire system,
+// under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+// SPDX-FileCopyrightText: Copyright (c) 2023 NVIDIA CORPORATION & AFFILIATES.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __CCCL_CONFIG
+#define __CCCL_CONFIG
+
+// Determine the host compiler
+#if defined(__NVCOMPILER)
+#  define _CCCL_COMPILER_NVHPC
+#elif defined(__clang__)
+#  define _CCCL_COMPILER_CLANG
+#elif defined(__GNUC__)
+#  define _CCCL_COMPILER_GCC
+#elif defined(_MSC_VER)
+#  define _CCCL_COMPILER_MSVC
+#elif defined(__IBMCPP__)
+#  define _CCCL_COMPILER_IBM
+#elif defined(__CUDACC_RTC__)
+#  define _CCCL_COMPILER_NVRTC
+#endif
+
+// Ensure cccl headers are treated as system headers when possible
+#if defined(_CCCL_NO_SYSTEM_HEADER)
+#  define _CCCL_IMPLICIT_SYSTEM_HEADER
+#elif defined(_CCCL_COMPILER_MSVC) \
+   && defined(_LIBCUDACXX_DISABLE_PRAGMA_MSVC_WARNING)
+#  define _CCCL_IMPLICIT_SYSTEM_HEADER
+#elif defined(_CCCL_COMPILER_NVRTC)
+#  define _CCCL_IMPLICIT_SYSTEM_HEADER
+#elif defined(_LIBCUDACXX_DISABLE_PRAGMA_GCC_SYSTEM_HEADER)
+#  define _CCCL_IMPLICIT_SYSTEM_HEADER
+#else
+#  if defined(_CCCL_COMPILER_GCC)
+#    define _CCCL_IMPLICIT_SYSTEM_HEADER _Pragma("GCC system_header")
+#  elif defined(_CCCL_COMPILER_CLANG)
+#    define _CCCL_IMPLICIT_SYSTEM_HEADER _Pragma("clang system_header")
+#  elif defined(_CCCL_COMPILER_MSVC)
+#    define _CCCL_IMPLICIT_SYSTEM_HEADER __pragma(system_header)
+#  elif defined(_CCCL_COMPILER_NVHPC)
+#    define _CCCL_IMPLICIT_SYSTEM_HEADER _Pragma("GCC system_header")
+#  else
+#    define _CCCL_IMPLICIT_SYSTEM_HEADER
+#  endif
+#endif
+
+_CCCL_IMPLICIT_SYSTEM_HEADER
+
+#endif // __CCCL_CONFIG

libcudacxx/include/cuda/std/detail/libcxx/include/__config

@@ -10,6 +10,10 @@
 #ifndef _LIBCUDACXX_CONFIG
 #define _LIBCUDACXX_CONFIG
 
+#include "__cccl_config"
+
+_CCCL_IMPLICIT_SYSTEM_HEADER
+
 #if defined(__NVCOMPILER)
 #  define _LIBCUDACXX_COMPILER_NVHPC
 #elif defined(__clang__)
@@ -83,32 +87,6 @@
 #  endif // !_LIBCUDACXX_DISABLE_PRAGMA_MSVC_WARNING
 #endif // _LIBCUDACXX_COMPILER_MSVC
 
-// allow disabling use as system header for testing
-#if defined(_CCCL_NO_SYSTEM_HEADER)
-#  define _CCCL_IMPLICIT_SYSTEM_HEADER
-#elif defined(_LIBCUDACXX_COMPILER_MSVC) \
-   && defined(_LIBCUDACXX_DISABLE_PRAGMA_MSVC_WARNING)
-#  define _CCCL_IMPLICIT_SYSTEM_HEADER
-#elif defined(_LIBCUDACXX_COMPILER_NVRTC)
-#  define _CCCL_IMPLICIT_SYSTEM_HEADER
-#elif defined(_LIBCUDACXX_DISABLE_PRAGMA_GCC_SYSTEM_HEADER)
-#  define _CCCL_IMPLICIT_SYSTEM_HEADER
-#else
-#  if defined(_LIBCUDACXX_COMPILER_GCC)
-#    define _CCCL_IMPLICIT_SYSTEM_HEADER _Pragma("GCC system_header")
-#  elif defined(_LIBCUDACXX_COMPILER_CLANG)
-#    define _CCCL_IMPLICIT_SYSTEM_HEADER _Pragma("clang system_header")
-#  elif defined(_LIBCUDACXX_COMPILER_MSVC)
-#    define _CCCL_IMPLICIT_SYSTEM_HEADER __pragma(system_header)
-#  elif defined(_LIBCUDACXX_COMPILER_NVHPC)
-#    define _CCCL_IMPLICIT_SYSTEM_HEADER _Pragma("GCC system_header")
-#  else
-#    define _CCCL_IMPLICIT_SYSTEM_HEADER
-#  endif
-#endif
-
-_CCCL_IMPLICIT_SYSTEM_HEADER
-
 #ifdef __cplusplus
 
 // __config may be included in `extern "C"` contexts, switch back to include <nv/target>

thrust/thrust/detail/config/config.h

@@ -21,7 +21,7 @@
 #pragma once
 
 // Include libcu++ config to get _CCCL_IMPLICIT_SYSTEM_HEADER
-#include <cuda/std/detail/__config>
+#include <cuda/__cccl_config>
 
 _CCCL_IMPLICIT_SYSTEM_HEADER