msvc with clangd

[RI-ss]

i use xmake to build a project in vscode
xmake can generate compile_commands for clangd
but here is a problem when toolchain is msvc

when the toolchain is clang,clangd work correctly

but i dont want to use clang,
when toolchain is msvc ,there are some problems
compile_commands changes to this

clangd starts to show errors

and exchange the line 1 and line 2
iostream cannt be found

the project are able to be built and run when toolchain is msvc , can not build correctly in clang

the main difference is the first element of argument,chang->cl,and it is automatically generated by xmake
is this generating right?
if it is right,what shold i to do to make it work?
if it is worng,what kind is right?

[i-ky]

I would suggest adding MSVC executable to --query-driver in clangd.arguments in VS Code settings. This will grant clangd permission to invoke compiler for the purpose of standard include path extraction.

[RI-ss]

like this?
but it doesnt work

[i-ky]

In your compile_commands.json it says ...\cl.exe, so query-driver should be ...\cl.exe too. There is a simple text based match algorithm behind.

Wih --log=verbose you should be able to troubleshoot, when clangd decides to invoke compiler and when not.

[HighCommander4]

I don't know if cl.exe supports the same flags (e.g. <driver> -E -v -x c++ -) that clangd uses to try to extract built-in includes from the driver.

[RI-ss]

ok,nothing changed

there is the output of clangd

I[18:42:19.443] <-- shutdown(8)
I[18:42:19.443] --> reply:shutdown(8) 0 ms
I[18:42:19.490] <-- exit
I[18:42:19.490] LSP finished, exiting with status 0
The flag -clang-tidy-checks is obsolete and ignored.
I[18:42:19.530] clangd version 15.0.7
I[18:42:19.532] Features: windows
I[18:42:19.532] PID: 10776
I[18:42:19.532] Working directory: d:/c++/test2
I[18:42:19.532] argv[0]: C:\msys64\mingw64\bin\clangd.exe
I[18:42:19.532] argv[1]: --background-index
I[18:42:19.532] argv[2]: --compile-commands-dir=.vscode
I[18:42:19.532] argv[3]: -j=13
I[18:42:19.532] argv[4]: --clang-tidy
I[18:42:19.532] argv[5]: --clang-tidy-checks=performance-,bugprone-
I[18:42:19.532] argv[6]: --all-scopes-completion
I[18:42:19.532] argv[7]: --completion-style=detailed
I[18:42:19.532] argv[8]: --header-insertion=iwyu
I[18:42:19.532] argv[9]: --pch-storage=memory
I[18:42:19.532] argv[10]: --header-insertion=never
I[18:42:19.532] argv[11]: --query-driver=C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.34.31933\bin\HostX64\x64\cl.exe
I[18:42:19.536] Starting LSP over stdin/stdout
I[18:42:19.537] <-- initialize(0)
I[18:42:19.539] --> reply:initialize(0) 2 ms
I[18:42:19.542] <-- initialized
I[18:42:19.551] <-- textDocument/didOpen
I[18:42:19.553] Loaded compilation database from d:/c++/test2/.vscode/compile_commands.json
I[18:42:19.553] --> window/workDoneProgress/create(0)
I[18:42:19.554] Enqueueing 1 commands for indexing
I[18:42:19.555] <-- reply(0)
I[18:42:19.555] --> $/progress
I[18:42:19.555] --> $/progress
I[18:42:19.563] <-- textDocument/documentSymbol(1)
I[18:42:19.564] <-- textDocument/codeAction(2)
I[18:42:19.611] <-- textDocument/documentLink(3)
I[18:42:19.612] <-- textDocument/inlayHint(4)
I[18:42:19.752] --> $/progress
I[18:42:19.753] --> $/progress
E[18:42:19.836] System include extraction: driver execution failed with return code: 2 - ''. Args: ["C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.34.31933\bin\HostX64\x64\cl.exe" -E -x c++ - -v]
I[18:42:19.837] ASTWorker building file d:/c++/test2/src/main.cpp version 6 with command
[d:\c++\test2]
"C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/MSVC/14.34.31933/bin/Hostx64/x64/cl.exe" --driver-mode=cl /c /nologo /O2 /fp:fast /std:c++20 "/Idependencies\include" /EHsc "/ID:\Program Files\vcpkg\installed\x64-windows-static\include" /DNDEBUG "/Fobuild\.objs\test2\windows\x64\release\src\main.cpp.obj" -resource-dir=C:/msys64/mingw64/lib/clang/15.0.7 -- d:/c++/test2/src/main.cpp
I[18:42:19.844] --> textDocument/clangd.fileStatus
I[18:42:20.317] --> workspace/semanticTokens/refresh(1)
I[18:42:20.318] <-- reply(1)
I[18:42:20.338] --> textDocument/publishDiagnostics
I[18:42:20.338] --> reply:textDocument/documentSymbol(1) 775 ms
I[18:42:20.339] --> reply:textDocument/codeAction(2) 774 ms
I[18:42:20.339] --> reply:textDocument/documentLink(3) 727 ms
I[18:42:20.339] --> reply:textDocument/inlayHint(4) 726 ms
I[18:42:20.339] --> textDocument/clangd.fileStatus
I[18:42:20.604] <-- textDocument/codeAction(5)
I[18:42:20.604] --> reply:textDocument/codeAction(5) 0 ms
I[18:42:20.604] --> textDocument/clangd.fileStatus
I[18:42:22.902] <-- textDocument/inlayHint(6)
I[18:42:22.902] --> reply:textDocument/inlayHint(6) 0 ms
I[18:42:22.902] --> textDocument/clangd.fileStatus
I[18:42:29.689] <-- textDocument/codeAction(7)
I[18:42:29.691] --> reply:textDocument/codeAction(7) 1 ms
I[18:42:29.691] --> textDocument/clangd.fileStatus

[i-ky]

As @HighCommander4 said, MSVC does not support flags that clangd is using for include path extraction:

E[18:42:19.836] System include extraction: driver execution failed with return code: 2 - ''. Args: ["C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.34.31933\bin\HostX64\x64\cl.exe" -E -x c++ - -v]

[HighCommander4]

Is there something preventing you from using a compile_commands.json generated with a clang toolchain, even as you use msvc for building?

[RI-ss]

no,
it is ok that all are accomplished in clang,
but i just am curious to find a way to use clangd in msvc,rather than code in clang and build in msvc

[xb284524239]

clangd could not query the standard library header path from msvc ( maybe a bug ? ).

So, you can add one line into the CMakeLists.txt of your project, like this:

include_directories("C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Tools\MSVC\14.29.30133\include")

[xb284524239]

[RI-ss]

确实是可以手动添加vs头
但是并不能正确识别vc的库

[laugh12321]

@RI-ss 若想要在VScode中使用Clangd用于MSVC项目提示，仅需在安装Visual Studio时，可选组件下选择“适用于 Windows 的 C++ Clang 编译器”来安装即可。

在VScode配置中添加clangd路径

"clangd.path": "C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/Llvm/bin/clangd.exe",

或者将C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\Llvm\bin添加至PATH即可

[xb284524239]

装 vs2022吧，我之前就是用的 vs2019，clangd 死活不能自动识别标准库。换成 vs2022 之后，无需任何手动添加的额外配置，clangd 自动完美识别。vs2022里面一定要装 C++ Build Insights 这个组件，它的作用是提高 MSVC 工具链的可见性。

[hxhc]

确实是可以手动添加vs头 但是并不能正确识别vc的库

可以把MSVC的include目录和lib目录放在环境变量里，虽然这样不太优雅