Build project using CMake, Ninja and clang for VS 2019 - c++

Question

So, I want to build my project using CMake and clang as a frontend for VS2019. What I already try:
CMakeLists.txt
cmake_minimum_required(VERSION 3.11 FATAL_ERROR)
#(CMAKE_INSTALL_PREFIX "C:\\Program Files\\LLVM\\bin")
project(sink)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -std=c++17 -pedantic")
set(SRC_DIR "${CMAKE_CURRENT_SOURCE_DIR}/src")
set(INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/include")
set(BUILD_DIR "${CMAKE_CURRENT_SOURCE_DIR}/build")
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${BUILD_DIR}/bin")
file(GLOB SOURCES "${SRC_DIR}/*.cpp" "${SRC_DIR}/*.cc" "${SRC_DIR}/*.c")
file(GLOB HEADERS "${INCLUDE_DIR}/*.h" "${INCLUDE_DIR}/*.hpp")
add_executable(${PROJECT_NAME} ${SOURCES} ${HEADERS})
CMakeSettings.json
{
"configurations": [
{
"name": "x64-Debug",
"generator": "Ninja",
"configurationType": "Debug",
"inheritEnvironments": [ "msvc_x64" ],
"buildRoot": "${env.USERPROFILE}\\CMakeBuilds\\${workspaceHash}\\build\\${name}",
"installRoot": "${env.USERPROFILE}\\CMakeBuilds\\${workspaceHash}\\install\\${name}",
"cmakeCommandArgs": "-H. -G Ninja -Bbuild -DCMAKE_CXX_COMPILER:PATH=\"C:\\Program Files\\LLVM\\bin\\clang-cl.exe\"",
"buildCommandArgs": "-v",
"ctestCommandArgs": "",
"variables": []
}
]
}
And which errors I get:
1> CMake generation started.
1> Command line: E:\VS19\COMMON7\IDE\COMMONEXTENSIONS\MICROSOFT\CMAKE\CMake\bin\cmake.exe -G "Ninja" -DCMAKE_INSTALL_PREFIX:PATH="C:\Users\theha\CMakeBuilds\7c084052-2033-9235-9a50-93f9ca5000be\install\x64-Debug" -DCMAKE_CXX_COMPILER:FILEPATH="E:/VS19/VC/Tools/MSVC/14.20.27404/bin/HostX86/x64/cl.exe" -DCMAKE_C_COMPILER:FILEPATH="E:/VS19/VC/Tools/MSVC/14.20.27404/bin/HostX86/x64/cl.exe" -H. -G Ninja -Bbuild -DCMAKE_CXX_COMPILER:PATH="C:\Program Files\LLVM\bin\clang-cl.exe" -DCMAKE_BUILD_TYPE="Debug" -DCMAKE_MAKE_PROGRAM="E:\VS19\COMMON7\IDE\COMMONEXTENSIONS\MICROSOFT\CMAKE\Ninja\ninja.exe" "C:\Users\theha\projects\sink"
1> Working directory: C:\Users\theha\CMakeBuilds\7c084052-2033-9235-9a50-93f9ca5000be\build\x64-Debug
1> [CMake] -- The C compiler identification is MSVC 19.20.27404.0
1> [CMake] -- The CXX compiler identification is Clang 7.0.1
1> [CMake] -- Check for working C compiler: E:/VS19/VC/Tools/MSVC/14.20.27404/bin/HostX86/x64/cl.exe
1> [CMake] -- Check for working C compiler: E:/VS19/VC/Tools/MSVC/14.20.27404/bin/HostX86/x64/cl.exe -- works
1> [CMake] -- Detecting C compiler ABI info
1> [CMake] -- Detecting C compiler ABI info - done
1> [CMake] -- Detecting C compile features
1> [CMake] -- Detecting C compile features - done
1> [CMake] -- Check for working CXX compiler: C:/Program Files/LLVM/bin/clang-cl.exe
1> [CMake] -- Check for working CXX compiler: C:/Program Files/LLVM/bin/clang-cl.exe -- broken
1> [CMake] CMake Error at E:/VS19/Common7/IDE/CommonExtensions/Microsoft/CMake/CMake/share/cmake-3.13/Modules/CMakeTestCXXCompiler.cmake:45 (message):
1> [CMake] The C++ compiler
1> [CMake]
1> [CMake] "C:/Program Files/LLVM/bin/clang-cl.exe"
1> [CMake]
1> [CMake] is not able to compile a simple test program.
1> [CMake]
1> [CMake] It fails with the following output:
1> [CMake]
1> [CMake] Change Dir: C:/Users/theha/CMakeBuilds/7c084052-2033-9235-9a50-93f9ca5000be/build/x64-Debug/build/CMakeFiles/CMakeTmp
1> [CMake]
1> [CMake] Run Build Command:"E:\VS19\COMMON7\IDE\COMMONEXTENSIONS\MICROSOFT\CMAKE\Ninja\ninja.exe" "cmTC_9e38f"
1> [CMake] [1/2] Building CXX object CMakeFiles\cmTC_9e38f.dir\testCXXCompiler.cxx.obj
1> [CMake] FAILED: CMakeFiles/cmTC_9e38f.dir/testCXXCompiler.cxx.obj
1> [CMake] C:\PROGRA~1\LLVM\bin\clang-cl.exe /nologo -TP /DWIN32 /D_WINDOWS /W3 /GR /EHsc /MDd /Zi /Ob0 /Od /RTC1 /JMC /showIncludes /FoCMakeFiles\cmTC_9e38f.dir\testCXXCompiler.cxx.obj /FdCMakeFiles\cmTC_9e38f.dir\ -c testCXXCompiler.cxx
1> [CMake] clang-cl.exe: error: no such file or directory: '/JMC'
1> [CMake] ninja: build stopped: subcommand failed.
1> [CMake]
1> [CMake]
1> [CMake]
1> [CMake]
1> [CMake] CMake will not be able to correctly generate this project.
1> [CMake] Call Stack (most recent call first):
1> [CMake] CMakeLists.txt:5 (project)
1> [CMake] -- Configuring incomplete, errors occurred!
1> [CMake] See also "C:/Users/theha/CMakeBuilds/7c084052-2033-9235-9a50-93f9ca5000be/build/x64-Debug/build/CMakeFiles/CMakeOutput.log".
1> [CMake] See also "C:/Users/theha/CMakeBuilds/7c084052-2033-9235-9a50-93f9ca5000be/build/x64-Debug/build/CMakeFiles/CMakeError.log".
1> [CMake]
1> CMake generation finished.
1> E:\VS19\COMMON7\IDE\COMMONEXTENSIONS\MICROSOFT\CMAKE\CMake\bin\cmake.exe -G "Ninja" -DCMAKE_INSTALL_PREFIX:PATH="C:\Users\theha\CMakeBuilds\7c084052-2033-9235-9a50-93f9ca5000be\install\x64-Debug" -DCMAKE_CXX_COMPILER:FILEPATH="E:/VS19/VC/Tools/MSVC/14.20.27404/bin/HostX86/x64/cl.exe" -DCMAKE_C_COMPILER:FILEPATH="E:/VS19/VC/Tools/MSVC/14.20.27404/bin/HostX86/x64/cl.exe" -H. -G Ninja -Bbuild -DCMAKE_CXX_COMPILER:PATH="C:\Program Files\LLVM\bin\clang-cl.exe" -DCMAKE_BUILD_TYPE="Debug" -DCMAKE_MAKE_PROGRAM="E:\VS19\COMMON7\IDE\COMMONEXTENSIONS\MICROSOFT\CMAKE\Ninja\ninja.exe" "C:\Users\theha\projects\sink" returned with exit code: 1
So, how I can fix that? Maybe I'm doing something wrong but I cannot understand what actually? I also see advices with using vcvarsall.bat and set CXX and CXXFLAGS but it isn't help.

Answer 1

There are two problems with your solution:
You are defining a build directory with "-Bbuild", which is different than the one defined in CMakeSettings.json in the "buildRoot" property. This would make Visual Studio misbehave, as e.g. it will look for CMakeCache.txt in the '${buildRoot}', not in '${buildRoot}/build'.
You are passing two definitions of CMAKE_CXX_COMPILER to CMake, one with "cl.exe", another with "clang-cl.exe".
You can solve both problems by passing these values instead:
{
"configurations": [
{
"name": "Debug",
"generator": "Ninja",
"configurationType": "Debug",
"inheritEnvironments": [
"msvc_x64"
],
"buildRoot": "${env.USERPROFILE}\\CMakeBuilds\\${workspaceHash}\\build\\${name}",
"installRoot": "${env.USERPROFILE}\\CMakeBuilds\\${workspaceHash}\\install\\${name}",
"cmakeCommandArgs": "",
"buildCommandArgs": "-v",
"ctestCommandArgs": "",
"variables": [
{
"name": "CMAKE_CXX_COMPILER",
"type": "PATH",
"value": "C:\\Program Files\\LLVM\\bin\\clang-cl.exe"
},
{
"name": "CMAKE_C_COMPILER",
"type": "PATH",
"value": "C:\\Program Files\\LLVM\\bin\\clang-cl.exe"
}
]
}
]
}
Regarding the error related to /JMC unrecognized flag being passed to clang-cl.exe, that flag is not currently supported by clang-cl.exe, so you need to apply this patch to your local CMake installation (located under
VS_INSTALLATION_FOLDER\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake)

Answer 2

Ok, maybe someone will find my solution useful.
How I change my CMakeLists.txt:
cmake_minimum_required(VERSION 3.11 FATAL_ERROR)
project(sink)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Xclang -std=c++17 -Xclang -pedantic")
set(SRC_DIR "${CMAKE_CURRENT_SOURCE_DIR}/src")
set(INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/include")
set(BUILD_DIR "${CMAKE_CURRENT_SOURCE_DIR}/build")
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${BUILD_DIR}/bin")
file(GLOB SOURCES "${SRC_DIR}/*.cpp" "${SRC_DIR}/*.cc" "${SRC_DIR}/*.c")
file(GLOB HEADERS "${INCLUDE_DIR}/*.h" "${INCLUDE_DIR}/*.hpp")
add_executable(${PROJECT_NAME} ${SOURCES} ${HEADERS})
And CMakeSettings.json:
{
"configurations": [
{
"name": "Debug",
"generator": "Ninja",
"configurationType": "Debug",
"inheritEnvironments": [ "msvc_x64" ],
"buildRoot": "${env.USERPROFILE}\\CMakeBuilds\\${workspaceHash}\\build\\${name}",
"installRoot": "${env.USERPROFILE}\\CMakeBuilds\\${workspaceHash}\\install\\${name}",
"cmakeCommandArgs": "-DCMAKE_CXX_COMPILER:PATH=\"C:\\Program Files\\LLVM\\bin\\clang-cl.exe\" -DCMAKE_CXX_FLAGS:STRING=\"/DWIN32 /D_WINDOWS /GR /EHsc\" -DCMAKE_CXX_FLAGS_DEBUG:STRING=\"/MDd /Zi /Ob0 /Od /RTC1\"",
"buildCommandArgs": "-v",
"ctestCommandArgs": "",
"variables": []
}
]
}
For now all works.