std::initializer_list does not contain the expected constructor

[Unturned3]

Type: Bug

Create the following .cpp file:

#include <vector>

int main()
{
    std::vector<int> v {1, 2, 3};
    return 0;
}

A red error squiggle will appear before the vector's uniform initialization list, with the message "the definition of std::initializer_list does not contain the expected constructor C/C++(2348)".

clang version:

$ clang -v
Homebrew clang version 18.1.4
Target: x86_64-apple-darwin23.3.0
Thread model: posix
InstalledDir: /usr/local/opt/llvm/bin

c_cpp_properties.json:

{
    "configurations": [
        {
            "name": "Mac",
            "includePath": [
                "${workspaceFolder}/**"
            ],
            "macFrameworkPath": [
                "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks"
            ],
            "compilerPath": "/usr/local/opt/llvm/bin/clang",
            "cppStandard": "c++17",
            "intelliSenseMode": "macos-clang-x64"
        }
    ],
    "version": 4
}

Extension version: 1.20.4 VS Code version: Code 1.88.1 (e170252f762678dec6ca2cc69aba1570769a5d39, 2024-04-10T17:42:52.765Z) OS version: Darwin x64 23.3.0 Modes:

System Info

|Item|Value| |---|---| |CPUs|Intel(R) Core(TM) i5-1038NG7 CPU @ 2.00GHz (8 x 2000)| |GPU Status|2d_canvas: enabled
canvas_oop_rasterization: disabled_off
direct_rendering_display_compositor: disabled_off_ok
gpu_compositing: enabled
multiple_raster_threads: enabled_on
opengl: enabled_on
rasterization: enabled
raw_draw: disabled_off_ok
skia_graphite: disabled_off
video_decode: enabled
video_encode: enabled
webgl: enabled
webgl2: enabled
webgpu: enabled| |Load (avg)|3, 4, 3| |Memory (System)|16.00GB (2.14GB free)| |Process Argv|--crash-reporter-id 7575e86b-e434-484d-8645-89363df807c7| |Screen Reader|no| |VM|0%|

A/B Experiments

``` vsliv368cf:30146710 vspor879:30202332 vspor708:30202333 vspor363:30204092 vscorecescf:30445987 vscod805:30301674 binariesv615:30325510 vsaa593:30376534 py29gd2263:31024239 c4g48928:30535728 azure-dev_surveyone:30548225 a9j8j154:30646983 962ge761:30959799 pythongtdpath:30769146 welcomedialogc:30910334 pythonidxpt:30866567 pythonnoceb:30805159 asynctok:30898717 pythontestfixt:30902429 pythonregdiag2:30936856 pyreplss1:30897532 pythonmypyd1:30879173 pythoncet0:30885854 h48ei257:31000450 pythontbext0:30879054 accentitlementst:30995554 dsvsc016:30899300 dsvsc017:30899301 dsvsc018:30899302 cppperfnew:31000557 ccp1r6:30993540 dsvsc020:30976470 pythonait:31006305 chatpanelt:31018789 dsvsc021:30996838 0ee40948:31013168 pythoncenvpt:31022790 a69g1124:31038041 dwnewjupytercf:31035177 ```

[sean-mcmanus]

@Unturned3 I don't repro the issue with the latest Apple clang (you're using the newer LLVM non-Apple clang though). Can you run the C/C++: Log Diagnostics command after opening the source file?

[Unturned3]

Hmm.. strange. I replaced /usr/local/opt/llvm/bin/clang with /usr/bin/clang for compilerPath (i.e. to use Apple's clang), and the issue disappeared. Why does this happen with Homebrew's latest clang though? What does that error message even mean?

Anyways, here's the C/C++: Log Diagonistics output:

-------- Diagnostics - 5/3/2024, 11:53:05 PM
Version: 1.20.4
Current Configuration:
{
    "name": "Mac",
    "includePath": [
        "/Users/richard/Desktop/T2/**"
    ],
    "macFrameworkPath": [
        "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks"
    ],
    "compilerPath": "/usr/local/opt/llvm/bin/clang",
    "cppStandard": "c++17",
    "intelliSenseMode": "macos-clang-x64",
    "compilerPathIsExplicit": true,
    "cStandardIsExplicit": false,
    "cppStandardIsExplicit": true,
    "intelliSenseModeIsExplicit": true,
    "compilerPathInCppPropertiesJson": "/usr/local/opt/llvm/bin/clang",
    "mergeConfigurations": false,
    "browse": {
        "path": [
            "/Users/richard/Desktop/T2/**",
            "${workspaceFolder}"
        ],
        "limitSymbolsToIncludedHeaders": true
    }
}
cpptools version (native): 1.20.4.0
No active translation units.

[sean-mcmanus]

@Unturned3 I'm not sure. I know a similar error can occur if c++03 is used. Are you able to compile/link? Have you tried changing it to /usr/local/opt/llvm/bin/clang++? If you use go to def on either the <vector> or std::vector and looked for the constructor taking an initializer list it might show as disabled due to some defines.

[Unturned3]

Yes, I am able to compile & link with the Homebrew clang just fine. No errors/warnings. I tried setting the compilerPath to /usr/local/opt/llvm/bin/clang++ but the error persisted. I did check the <vector> header, but unfortunately my C++ knowledge is nowhere good enough for me to understand the mess in there.

[MinetaS]

This happens on Windows with msys clang 18.1.3 as well. Apparently, the error appears only when <initializer_list> is included before <vector>. Including <initializer_list> after <vector> does not have the problem.

To reproduce, create an empty workspace and write a simple C++ code:

// The error only appears if initializer_list is included before vector
#include <initializer_list>
#include <vector>

int main() {
    std::vector<int> v{1, 2, 3};
    return 0;
}

c_cpp_properties.json:

{
    "configurations": [
        {
            "name": "Win32",
            "includePath": [
                "${workspaceFolder}/**"
            ],
            "defines": [],
            "compilerPath": "C:\\\\msys64\\\\clang64\\\\bin\\\\x86_64-w64-mingw32-clang++.exe",
            "intelliSenseMode": "windows-clang-x64",
            "cStandard": "c17",
            "cppStandard": "c++17",
            "compilerArgs": [
                "--std=c++17"
            ]
        }
    ],
    "version": 4
}

C/C++: Log Diagnostics:

-------- Diagnostics - 5/6/2024, 2:48:50 AM
Version: 1.20.4
Current Configuration:
{
    "name": "Win32",
    "includePath": [
        "c:/Users/skdty/repos/test/**"
    ],
    "defines": [],
    "compilerPath": "C:\\\\msys64\\\\clang64\\\\bin\\\\x86_64-w64-mingw32-clang++.exe",
    "intelliSenseMode": "windows-clang-x64",
    "cStandard": "c17",
    "cppStandard": "c++17",
    "compilerArgs": [
        "--std=c++17"
    ],
    "compilerPathIsExplicit": true,
    "cStandardIsExplicit": true,
    "cppStandardIsExplicit": true,
    "intelliSenseModeIsExplicit": true,
    "compilerPathInCppPropertiesJson": "C:\\\\msys64\\\\clang64\\\\bin\\\\x86_64-w64-mingw32-clang++.exe",
    "windowsSdkVersion": "10.0.22621.0",
    "mergeConfigurations": false,
    "browse": {
        "path": [
            "c:/Users/skdty/repos/test/**",
            "${workspaceFolder}"
        ],
        "limitSymbolsToIncludedHeaders": true
    }
}
cpptools version (native): 1.20.4.0
Translation Unit Mappings:
[ C:\Users\skdty\repos\test\test.cc - source TU]:
Translation Unit Configurations:
[ C:\Users\skdty\repos\test\test.cc ]:
    Process ID: 20808
    Memory Usage: 206 MB
    Compiler Path: C:\msys64\clang64\bin\x86_64-w64-mingw32-clang++.exe
    Includes:
        C:\msys64\clang64\include\c++\v1
        C:\msys64\clang64\lib\clang\18\include
        C:\msys64\clang64\include
    Standard Version: c++17
    IntelliSense Mode: windows-clang-x64
    Other Flags:
        --clang
        --clang_version=180103
Total Memory Usage: 206 MB

------- Workspace parsing diagnostics -------
Number of files discovered (not excluded): 6035

[browntarik]

@Unturned3 @MinetaS Does the issue persist when changing your IntelliSense Mode to *-clang-x86?

[MinetaS]

@browntarik Yes, for windows-clang-x86 the issue persists. Along with the compiler path set to C:\msys64\clang32\bin\i686-w64-mingw32-clang++.exe.

[SomedudeX]

I also have the same issue after updating my homebrew clangd to 18.1.6. Perhaps the cpptools extension does not recognize the updated header files, and treated/parsed the initializer list class as a normal class as opposed to a language supported and defined standard, which ultimately resulted in it not being able to find a suitable constructor?

Either way I really hope this gets updated/fixed soon by the team™

[browntarik]

@MinetaS I am having trouble installing your compiler with a version of 18.x, could you walk me through some steps on how to acquire your compiler?

We are currently out of date with the version numbers of compilers that our IntelliSense supports, and those numbers will be updated but being able to get a clang compiler with the correct version will help with testing.

[MinetaS]

@browntarik Sorry for the late response. Somehow I unsubscribed this issue by mistake.

It's the official clang/llvm package from msys2. https://packages.msys2.org/package/mingw-w64-x86_64-clang

pacman -S mingw-w64-x86_64-clang

in msys2 terminal will install it. The compiler path is mentioned in my previous comment above.

[browntarik]

Thanks for the information, we have been able to reproduce this bug. This issue has been reported to our internal team (VS: 2171136). Please follow this issue for more updates on when it has been fixed.