command-line error: language modes specified are incompatibleC/C++(1027)

[thselukas]

Environment

• OS and Version: Windows 11, Version 10.0.22621 Build 22621
• VS Code Version: 1.74.2
• C/C++ Extension Version: v1.13.8

Bug Summary and Steps to Reproduce

Bug Summary:
When a c file is created, the first line is underlined and marked as an error (command-line error: language modes specified are incompatibleC/C++(1027)

Steps to reproduce:

• Create a c file
• Write a line (for example #include <stdio.h>
• Error is displayed with the only quick fix: Disable error squiggels

Expected behavior:

• No error should be displayed

Configuration and Logs

c_cpp_properties.json
{
    "configurations": [
        {
            "name": "Win32",
            "includePath": [
                "${workspaceFolder}/**"
            ],
            "defines": [
                "_DEBUG",
                "UNICODE",
                "_UNICODE"
            ],
            "windowsSdkVersion": "10.0.19041.0",
            "compilerPath": "C:/MinGW/bin/gcc.exe",
            "cStandard": "c17",
            "cppStandard": "c++17",
            "intelliSenseMode": "gcc-x64",
            "configurationProvider": "ms-vscode.makefile-tools"
        }
    ],
    "version": 4
}

Other Extensions

All other Extensions for C/C++ were uninstalled but the issue still persists.

Additional context

Example:

#include <stdio.h> // The error is visible in this line at the "#" symbol

int main(int argc, char const *argv[])
{
    printf("Hello World!");
    return 0;
}

The file can be compiled with the "run C/C++" dropdown option, but Intellisense doesn't work properly.

[sean-mcmanus]

I transferred the issue. I'm guessing the Makefile Tools extension is sending us invalid compiler args. Providing logs from running the C/C++: Log Diagnostics command would help. However, I also noticed this similar issue at #9684.

[thselukas]

I transferred the issue. I'm guessing the Makefile Tools extension is sending us invalid compiler args. Providing logs from running the C/C++: Log Diagnostics command would help. However, I also noticed this similar issue at microsoft/vscode-cpptools#9684.

Here is the output of the Log Diagnostics Command:

-------- Diagnostics - 28.12.2022, 12:33:48
Version: 1.13.8
Current Configuration:
{
    "name": "Win32",
    "includePath": [
        "${workspaceFolder}/**"
    ],
    "defines": [
        "_DEBUG",
        "UNICODE",
        "_UNICODE"
    ],
    "windowsSdkVersion": "10.0.19041.0",
    "compilerPath": "C:/MinGW/bin/gcc.exe",
    "cStandard": "c17",
    "cppStandard": "c++17",
    "intelliSenseMode": "gcc-x64",
    "configurationProvider": "ms-vscode.makefile-tools",
    "compilerPathIsExplicit": true,
    "cStandardIsExplicit": true,
    "cppStandardIsExplicit": true,
    "intelliSenseModeIsExplicit": true,
    "mergeConfigurations": false,
    "browse": {
        "path": [
            "${workspaceFolder}/**"
        ],
        "limitSymbolsToIncludedHeaders": true
    }
}
Custom browse configuration: 
{
    "browsePath": [
        "c:\\Users\\[User Account]\\Downloads\\encrypt_decrypt"
    ],
    "compilerPath": "C:\\WIN-GW\\bin\\gcc.exe",
    "compilerArgsLegacy": [
        "-o",
        "encrypt.exe"
    ]
}
Translation Unit Mappings:
[ C:\Users\[User Account]\VSCODE-C\hello-world\src\hello-world.c ]:
    C:\Users\[User Account]\VSCODE-C\hello-world\src\hello-world.c
Translation Unit Configurations:
[ C:\Users\[User Account]\VSCODE-C\hello-world\src\hello-world.c ]:
    Process ID: 3440
    Memory Usage: 39 MB
    Compiler Path: C:\WIN-GW\bin\gcc.exe
    Includes:
        C:\WIN-GW\include
        C:\WIN-GW\include\c++\4.8.3
        C:\WIN-GW\include\c++\4.8.3\x86_64-w64-mingw32
        C:\WIN-GW\include\c++\4.8.3\backward
        C:\WIN-GW\lib64\gcc\x86_64-w64-mingw32\4.8.3\include
        C:\WIN-GW\lib64\gcc\x86_64-w64-mingw32\4.8.3\include-fixed
        C:\WIN-GW\x86_64-w64-mingw32\include
    Standard Version: c17
    IntelliSense Mode: windows-gcc-x64
    Other Flags:
        --g++
        --gnu_version=40803
Total Memory Usage: 39 MB

------- Workspace parsing diagnostics -------
Number of files discovered (not excluded): 102816

[sean-mcmanus]

I moved it back since the logging indicates it's not a Makefile Tools issue.

We're hitting some problem processing the output from your older compiler. The issue might be fixed if you can switch to a newer compiler version.

Otherwise, can you provide the C/C++ logging when C_Cpp.loggingLevel is set to "Debug" -- the logging during startup should be sufficient (with a .c file active).

[thselukas]

Thank you. By updating GCC to the version 12.2.0 the Issue has now resolved itself. Thanks for your help.