# Setup C++ 20 VSCode environment on Ubuntu

This article will set up following tools to develop with C++ 20 in VSCode. My Ubuntu version is 22.04.
>gcc 13.1.0 / g++ 13.1.0
>clang-format
>C/C++ Settings
>C/C++ Advanced Lint

## GCC
The default gcc on Ubuntu is only at 11, which is not suitable if you want to use C++ >=20 features like `std::format`.

Source: [Install gcc 13 on Ubuntu 22.04
](https://www.mindthink.me/2024/03/14/install-gcc-13-on-ubuntu-22-04/)

1. add the repository

sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test

2. install gcc 13

sudo apt-get install gcc-13

3. install g++ 13, because g++ 13 is not the same as gcc 13

sudo apt-get install g++-13

4. update the default gcc/g++ version to 13

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-13 130 --slave /usr/bin/g++ g++ /usr/bin/g++-13

5. Verify the installed version

gcc --version

Following text should be shown.

gcc (Ubuntu 13.1.0-8ubuntu1~22.04) 13.1.0
Copyright (C) 2023 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

The `gcc` and `g++` should be installed at `/usr/bin/gcc` and `usr/bin/g++` respectively.

## Clang-format
Clang-format helps to format C++ code. Unformatted code harms readability!

Install clang-format

sudo apt install clang-format

Create a `.clang-format` in your project root directory, and paste the content from [this clang format template gist](https://gist.github.com/gelldur/d7bc3ea226aebcf8cc879df1e8524236).

Try it on your unformatted code by clicking save!

## C/C++ Settings
Press `Ctrl+Shift+P` to open the panel, then search C/C++ to find `C/C++ Edit Configurations (JSON)`, so we don't need to search for each setting, instead we just type it out.

Paste the following contents to the opened json. The `/usr/include/c++/**` contains the c++ header files. If you have installed `gcc/g++ 13.1.0`, you will have `/usr/include/c++/13` in your computer.

{
    "configurations": [
        {
            "name": "Linux",
            "includePath": [
                "${workspaceFolder}/**",
                "/usr/include/c++/**",
                "/usr/include/**"
            ],
            "defines": [],
            "compilerPath": "/usr/bin/g++",
=            "cppStandard": "c++20",
            "intelliSenseMode": "linux-gcc-x64"
        }
    ],
    "version": 4
}

## C/C++ Advanced Lint
`C/C++ Advanced Lint` is a vscode extension, please install it in your vscode.


It would need a static code analyzer to work. The extension description has listed the supported analyzers, including `Clang`, `CppCheck` etc. Personally I choose `Clang`. Please install it with following command:

sudo apt-get install clang

Same as above, we would edit the setting json to configure the linter. Before that, I would suggest saving the existing project as a vscode workspace, so the settings can be restricted to this project only.

Press `Ctrl+Shift+P` to toggle the panel, then search for `save work` to save the workspace. Please save the workspace to the project root directory. After that, a [ProjectName].code-workspace file will be created.

Open the workspace file, it is a json. Paste the following contents to it. The setting names are quite descriptive. For the clang executable, it is usually at `/usr/bin/clang`, if not, please find it with `whereis clang`. Since I only installed one static code analyzer, I disable others in the last few lines such as `"c-cpp-flylint.cppcheck.enable": false,`, this is to prevent the frequent warning about xxx analyzer is not found by the extension.

{
	"folders": [
		{
			"path": "."
		}
	],
	"settings": {
		"C_Cpp.default.cppStandard": "c++20",
		"c-cpp-flylint.clang.enable": true,
		"c-cpp-flylint.clang.executable": "/usr/bin/clang",
		"c-cpp-flylint.debug": true,
		"c-cpp-flylint.clang.standard": ["c++20"],
		"c-cpp-flylint.includePaths": [
			"/usr/include/c++/*",
			"/usr/include"
		],
		"c-cpp-flylint.clang.includePaths": [
			"/usr/include/c++/*",
			"/usr/include"
		],
		"C_Cpp.default.intelliSenseMode": "linux-gcc-x64",
		"C_Cpp.inlayHints.autoDeclarationTypes.enabled": true,
		"c-cpp-flylint.cppcheck.enable": false,
		"c-cpp-flylint.flexelint.enable": false,
		"c-cpp-flylint.flawfinder.enable": false,
		"c-cpp-flylint.lizard.enable": false,
	}
}

## About Me
A self-motivated programmer who is exploring low-latency C++.

>Personal Website: https://jacky-chen-portfolio.vercel.app/
>GitHub: https://github.com/TypeErrorEngine2022
>Email: [e-mail]