Intellisense doesn't parse system includes correctly

[nolankramer]

Type: Bug

System includes are completely broken with clang and libstdc++. Intellisense claims std::filesystem::path is not a type, among other things.

This obviously causes a massive amount of "errors" to show up in the editor.

Here's my clang -v:

Ubuntu clang version 18.1.3 (1ubuntu1)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/13
Selected GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/13
Candidate multilib: .;@m64
Selected multilib: .;@m64

And my Linux configuration in c_cpp_properties.json:

{
            "name": "Linux",
            "includePath": [
                "${workspaceFolder}/**"
            ],
            "defines": [],
            "compilerPath": "/usr/bin/clang++",
            "cStandard": "c17",
            "cppStandard": "c++17",
            "intelliSenseMode": "linux-clang-x64",
            "configurationProvider": "ms-vscode.cmake-tools"
        }

The std version being passed into the compile commands is: -std=gnu++17

Extension version: 1.21.6
VS Code version: Code 1.93.1 (38c31bc77e0dd6ae88a4e9cc93428cc27a56ba40, 2024-09-11T17:20:05.685Z)
OS version: Linux x64 6.8.0-45-generic snap
Modes:

System Info

Item	Value
CPUs	AMD Ryzen 7 PRO 6850H with Radeon Graphics (16 x 2393)
GPU Status	2d_canvas: unavailable_software canvas_oop_rasterization: disabled_off direct_rendering_display_compositor: disabled_off_ok gpu_compositing: disabled_software multiple_raster_threads: enabled_on opengl: disabled_off rasterization: disabled_software raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: disabled_software video_encode: disabled_software vulkan: disabled_off webgl: unavailable_software webgl2: unavailable_software webgpu: disabled_off webnn: disabled_off
Load (avg)	2, 1, 2
Memory (System)	14.89GB (7.96GB free)
Process Argv	--no-sandbox --force-user-env --crash-reporter-id 0075ae52-00ae-4c27-9257-6ea0067d3b86
Screen Reader	no
VM	0%
DESKTOP_SESSION	plasma
XDG_CURRENT_DESKTOP	KDE
XDG_SESSION_DESKTOP	KDE
XDG_SESSION_TYPE	x11

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[Colengms]

Hi @nolankramer . I'm not easily able to repro an issue with the configuration you provided (without the custom configuration provider specified), clang 18.1.3, and the following code:

#include <filesystem>

void foo()
{
    std::filesystem::path a;
}

However, your configuration does include:

"configurationProvider": "ms-vscode.cmake-tools"

So your IntelliSense configuration may be based on whatever CMake Tools has provided (which would require a CMakeLists.txt and have specified the source file there).

We are aware of the following issue with clang 18. You might try the work around here: #12618

[nolankramer]

Thanks for the reply @Colengms ! I tried the workaround, but no luck - same issues.

How can I provide more information about the CMake setup without pasting the CMakeLists.txt here, since the project is proprietary?

Is there specific CMake values you'd like to know about?

If it helps, here's the clang switches I see in the compile_commands.json: -g -fstandalone-debug -std=gnu++17

[nolankramer]

Interestingly, removing the "configurationProvider": "ms-vscode.cmake-tools" configuration value does fix the issue. Which makes me wonder what I could possibly be doing wrong in the CMakeLists.txt...

[bobbrow]

I tried the workaround, but no luck - same issues.

If you are using the configuration provider, I believe the workaround also required setting mergeConfigurations to true. However, we put the workaround into our main configurations starting in 1.22.4 so that it should hopefully apply globally to everyone without having to fiddle with configurations.

[nolankramer]

Yes it looks like setting mergeConfigurations to true fixes the issue when using the configuration provider.

This can be closed since there are now two solutions, with backend changes pending to ease setup.