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How to Check C Version in Visual Studio Code

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1 hour ago

Working with C in Visual Studio Code (VS Code) is a popular choice among developers due to its lightweight design, customization flexibility, and rich extension support. Whether you’re just starting with C programming or diving into an existing codebase, one essential element to keep track of is which version of the C compiler you’re using. Knowing this helps you avoid compatibility issues and ensures that your code adheres to the desired C language standard.

TL;DR

To check the C compiler version in Visual Studio Code, install a C compiler such as GCC or Clang, and use the Terminal in VS Code to run the version command (like gcc --version). Ensure your environment variables (like PATH) are properly configured. You can also set compiler paths and flags in the tasks.json or c_cpp_properties.json files to manage versions more robustly. Checking the version helps ensure consistency between development and deployment environments.

Why Checking the C Version Matters

Different versions of the C programming language (C89, C99, C11, C18, etc.) come with unique features and syntax enhancements. Your compiler’s support for these versions can directly impact how your program compiles and runs. If you’re collaborating on a project or using third-party libraries, it’s especially critical to make sure everyone is on the same version to avoid unwanted behavior or compiler errors.

Step-by-Step Guide to Check C Version in Visual Studio Code

1. Ensure That a C Compiler is Installed

VS Code is not a compiler itself—it is a code editor. So first, you need a proper C compiler installed on your system, such as:

  • GCC (GNU Compiler Collection) for Linux or Windows via MinGW or WSL
  • Clang for macOS and Unix-based systems
  • Microsoft’s MSVC for Windows through the Build Tools for Visual Studio

You can verify installation by opening a terminal and typing one of the following commands:

gcc --version
clang --version
cl

If any of these return valid output with version numbers, your compiler is installed correctly.

2. Open Visual Studio Code Terminal

You can open the terminal in Visual Studio Code using:

  • Menu: Terminal > New Terminal
  • Shortcut: Ctrl + ` (the grave accent key below Esc)

Once your terminal is open, type the appropriate command mentioned above to see your C compiler’s version.

3. Install the C/C++ Extension in VS Code

Although optional for checking version, installing the C/C++ extension by Microsoft enhances functionality. It provides syntax highlighting, linting, IntelliSense, debugger support, and builds easier code navigation.

To install:

  • Go to the Extensions sidebar (Ctrl+Shift+X)
  • Search for “C/C++“
  • Click Install

4. Check Compiler Version from a Code File

You can write a simple C program that identifies the compiler version during compilation. Here’s an example:

#include <stdio.h>

int main() {
#ifdef __clang__
    printf("Using Clang version %d.%d.%d\n", __clang_major__, __clang_minor__, __clang_patchlevel__);
#elif defined(__GNUC__) || defined(__GNUG__)
    printf("Using GCC version %d.%d.%d\n", __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
#elif defined(_MSC_VER)
    printf("Using MSVC version %d\n", _MSC_VER);
#else
    printf("Unknown compiler\n");
#endif

    return 0;
}

Compile and run the program in your debugger terminal or terminal window. This gives you a programmatic way to determine the version inside your code base.

5. Use tasks.json to Automate the Check

In VS Code, you can define build tasks that automate compilation commands. This is found in the .vscode folder.

  • Go to Terminal > Configure Tasks
  • Choose your environment (e.g., GCC or Clang)

Here’s a sample tasks.json that builds with GCC and can include version checking:

{
  "version": "2.0.0",
  "tasks": [
    {
      "label": "Check GCC Version",
      "type": "shell",
      "command": "gcc --version",
      "group": {
        "kind": "build",
        "isDefault": true
      },
      "problemMatcher": []
    }
  ]
}

With this setup, every time you build or run, you can include a version check alongside your executable.

6. View Compiler Configuration in c_cpp_properties.json

The c_cpp_properties.json file helps define compiler paths and IntelliSense modes based on your toolchain. This file also helps VS Code detect the version of the compiler used for intelligent code completion.

Located at .vscode/c_cpp_properties.json, sample snippet:

{
  "configurations": [
    {
      "name": "Win32",
      "includePath": ["${workspaceFolder}/"],
      "defines": ["_DEBUG", "UNICODE"],
      "windowsSdkVersion": "10.0.19041.0",
      "compilerPath": "C:/MinGW/bin/gcc.exe",
      "cStandard": "c11",
      "intelliSenseMode": "gcc-x64"
    }
  ],
  "version": 4
}

Setting the correct compilerPath ensures version synchronization with your actual code compilation process.

Common Issues and Troubleshooting

1. “gcc not recognized” or similar errors

Make sure your compiler’s bin directory (e.g., C:/MinGW/bin for gcc) is added to your system’s PATH environment variable. Otherwise, your terminal won’t find the compiler executable.

2. Mismatched IntelliSense Version

Sometimes VS Code’s IntelliSense is not using the same compiler or version as your terminal. To fix this, ensure compilerPath in c_cpp_properties.json points to the correct executable.

3. Outdated Compiler Version

If you notice your compiler doesn’t support newer standards like C11 or C18, you may need to update your compiler. On Linux, use:

sudo apt update
sudo apt install gcc

On Windows, installing a MinGW-w64 build or updating via Chocolatey helps.

Final Tips

  • Use version flags: When compiling manually, use flags like -std=c11 to enforce a specific standard version.
  • Keep compilers updated: Regular updates help you benefit from bug fixes, security updates, and new language features.
  • Consistency is key: Match compiler versions across your team or CI/CD pipeline for predictable builds.

Conclusion

Checking your C compiler version in Visual Studio Code is a crucial part of the development workflow. Whether you’re debugging, building for multiple environments, or just want cleaner code, knowing your compiler version gives you the control and clarity you need. With this guide, configuring and confirming the version in various ways—from terminal commands to JSON configuration—becomes an integral part of your workflow. VS Code’s flexibility combined with your favorite C compiler lets you build powerful and compatible applications.