IntelliSense wrongly underlined error if Explicit Object Parameter, Type Conversion Operator, and Template are used together.

[bionukg]

Environment

• OS and Version: Windows_NT x64 10.0.19045
• VS Code Version: 1.96.0
• C/C++ Extension Version: 1.22.11, updated at 2024-11-06, 19:45:17
• If using SSH remote, specify OS of remote machine: none

Bug Summary and Steps to Reproduce

Bug Summary:
IntelliSense error if Explicit Object Parameter, Type Conversion Operator, and Template are used together.

Steps to reproduce:

1. create a new file named 'bug.cpp' (use cppStandard c++23).
2. copy the code below into it:

struct A
{
    template <typename T>
    operator int(this T & self) { return 1; }
    operator char(this auto &self) { return 2; }
};

int main()
{
    A a;
    int i = a;
    int j = int(a);
    char k = char(a);
    return i;
}

2. some codes are red underlined.

Expected behavior:
there should be no red underlined code.

Configuration and Logs

-------- Diagnostics - 2024/12/15 22:08:22
Version: 1.22.11
Current Configuration:
{
    "name": "Win32",
    "includePath": [
        "${workspaceFolder}/**"
    ],
    "defines": [
        "_DEBUG",
        "UNICODE",
        "_UNICODE"
    ],
    "windowsSdkVersion": "10.0.26100.0",
    "compilerPath": "cl.exe",
    "cStandard": "c17",
    "intelliSenseMode": "windows-msvc-x64",
    "compilerPathInCppPropertiesJson": "cl.exe",
    "cppStandard": "c++23",
    "intelliSenseModeIsExplicit": false,
    "cStandardIsExplicit": false,
    "cppStandardIsExplicit": true,
    "mergeConfigurations": false,
    "compilerPathIsExplicit": false,
    "browse": {
        "path": [
            "${workspaceFolder}/**"
        ],
        "limitSymbolsToIncludedHeaders": true
    }
}
Modified Settings:
{
    "C_Cpp.inlayHints.autoDeclarationTypes.enabled": true,
    "C_Cpp.inlayHints.parameterNames.enabled": true,
    "C_Cpp.default.cppStandard": "c++23"
}
Additional Tracked Settings:
{
    "editorTabSize": 4,
    "editorInsertSpaces": true,
    "editorAutoClosingBrackets": "languageDefined",
    "filesEncoding": "utf8",
    "filesAssociations": {
        "*.vt": "verilog",
        "*.ixx": "cpp",
        "*.asm": "masm"
    },
    "filesExclude": {
        "**/.git": true,
        "**/.svn": true,
        "**/.hg": true,
        "**/CVS": true,
        "**/.DS_Store": true,
        "**/Thumbs.db": true
    },
    "filesAutoSaveAfterDelay": true,
    "editorInlayHintsEnabled": true,
    "editorParameterHintsEnabled": true,
    "searchExclude": {
        "**/node_modules": true,
        "**/bower_components": true,
        "**/*.code-search": true
    },
    "workbenchSettingsEditor": "ui"
}
cpptools version (native): 1.22.11.0
Current database path: C:\USERS\BIONUKG\APPDATA\LOCAL\TEMP\{0034E163-EF00-48B0-8732-7DB74FF7DE52}\.BROWSE.VC.DB
Translation Unit Mappings:
[ C:\Users\bionukg\Desktop\bug\bug.cpp - source TU]:
Translation Unit Configurations:
[ C:\Users\bionukg\Desktop\bug\bug.cpp ]
    Process ID: 15812
    Memory Usage: 51 MB
    Compiler Path: C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.42.34433\bin\Hostx64\x64\cl.exe
    Includes:
    System Includes:
        C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.42.34433\include
        C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.42.34433\atlmfc\include
        C:\Program Files (x86)\Windows Kits\10\Include\10.0.26100.0\um
        C:\Program Files (x86)\Windows Kits\10\Include\10.0.26100.0\ucrt
        C:\Program Files (x86)\Windows Kits\10\Include\10.0.26100.0\shared
        C:\Program Files (x86)\Windows Kits\10\Include\10.0.26100.0\winrt
        C:\Program Files (x86)\Windows Kits\10\Include\10.0.26100.0\cppwinrt
    Defines:
        _DEBUG
        UNICODE
        _UNICODE
    Standard Version: ms_c++latest
    IntelliSense Mode: windows-msvc-x64
Total Memory Usage: 51 MB

Other Extensions

No response

Additional context

[sean-mcmanus]

@bionukg I've reported a bug on our shared VS parser at https://developercommunity.visualstudio.com/t/C-IntelliSense-error-with-C23-explic/10813897 .

[Vaibhav75058]

i am aslo facing the same isssue after installing c/c++ intellisense extention showing red error line under the # of include file
#include
using namespace std;
int main()