Merge pull request NVIDIA#1452 from NVIDIA/better-clangd-integration

help clangd find the compilation database for IDE code complete goodness

Author: ericniebler

.gitignore

@@ -13,3 +13,4 @@ callgrind.*
 *.o
 a.out
 *.code-workspace
+sanitizer-ignorelist.txt

CMakeLists.txt

@@ -68,7 +68,7 @@ message(STATUS "Build year       : ${STDEXEC_BUILD_YEAR}")
 message(STATUS)
 
 # Integrate with LLVM/clang tooling
-set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/clangd_compile_info.cmake)
 
 # Write the version header
 rapids_cmake_write_version_file(include/stdexec_version_config.hpp)

cmake/clangd_compile_info.cmake

@@ -0,0 +1,30 @@
+# SPDX-FileCopyrightText: Copyright (c) 2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/cmake_utilities.cmake)
+
+# Tell cmake to generate a json file of compile commands for clangd:
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+
+# Symlink the compile command output to the source dir, where clangd will find it.
+set(compile_commands_file "${CMAKE_BINARY_DIR}/compile_commands.json")
+set(compile_commands_link "${CMAKE_SOURCE_DIR}/compile_commands.json")
+message(STATUS "Creating symlink from ${compile_commands_link} to ${compile_commands_file}...")
+stdexec_execute_non_fatal_process(COMMAND
+  "${CMAKE_COMMAND}" -E rm -f "${compile_commands_link}")
+stdexec_execute_non_fatal_process(COMMAND
+  "${CMAKE_COMMAND}" -E touch "${compile_commands_file}")
+stdexec_execute_non_fatal_process(COMMAND
+  "${CMAKE_COMMAND}" -E create_symlink "${compile_commands_file}" "${compile_commands_link}")

cmake/cmake_utilities.cmake

@@ -0,0 +1,45 @@
+# SPDX-FileCopyrightText: Copyright (c) 2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Passes all args directly to execute_process while setting up the following
+# results variables and propagating them to the caller's scope:
+#
+# - stdexec_process_exit_code
+# - stdexec_process_stdout
+# - stdexec_process_stderr
+#
+# If the command
+# is not successful (e.g. the last command does not return zero), a non-fatal
+# warning is printed.
+function(stdexec_execute_non_fatal_process)
+  execute_process(${ARGN}
+    RESULT_VARIABLE stdexec_process_exit_code
+    OUTPUT_VARIABLE stdexec_process_stdout
+    ERROR_VARIABLE stdexec_process_stderr
+  )
+
+  if (NOT stdexec_process_exit_code EQUAL 0)
+    message(WARNING
+      "execute_process failed with non-zero exit code: ${stdexec_process_exit_code}\n"
+      "${ARGN}\n"
+      "stdout:\n${stdexec_process_stdout}\n"
+      "stderr:\n${stdexec_process_stderr}\n"
+    )
+  endif()
+
+  set(stdexec_process_exit_code "${stdexec_process_exit_code}" PARENT_SCOPE)
+  set(stdexec_process_stdout "${stdexec_process_stdout}" PARENT_SCOPE)
+  set(stdexec_process_stderr "${stdexec_process_stderr}" PARENT_SCOPE)
+endfunction()

include/stdexec/__detail/__transform_completion_signatures.hpp

@@ -20,7 +20,7 @@
 // include these after __execution_fwd.hpp
 #include "__completion_signatures.hpp"
 #include "__concepts.hpp"
-#include "__debug.hpp"
+#include "__debug.hpp" // IWYU pragma: keep
 #include "__diagnostics.hpp"
 #include "__senders_core.hpp"
 #include "__meta.hpp"