vscode cmake tools debug

2 min read 14-10-2024

Debugging CMake projects in Visual Studio Code (VSCode) can be a seamless experience with the right tools and configurations. This article will guide you through setting up and debugging your CMake projects efficiently using VSCode.

Prerequisites

Before you begin, make sure you have the following installed:

Visual Studio Code: Download and install the latest version from the official website.
CMake: Install CMake from the CMake website.
C/C++ Extension for VSCode: This is necessary for debugging C++ code. You can find it in the VSCode marketplace.
CMake Tools Extension: This extension simplifies the process of building and debugging CMake projects.

Setting Up Your CMake Project

Open Your Project: Launch VSCode and open the folder containing your CMake project.
Configure CMake:
- Use the Command Palette (Ctrl+Shift+P) and type CMake: Configure. This will run the CMake configuration process, generating build files.
Build Your Project:
- Again, use the Command Palette and select CMake: Build. This command will compile your code, and if successful, you’ll see build output in the terminal.

Debugging Your CMake Project

Create a Launch Configuration

Open the Debug View: Click on the Debug icon on the sidebar or use the shortcut Ctrl+Shift+D.
Add Configuration:
- Click on the gear icon to create a launch.json file.
- Choose C++ (GDB/LLDB) or the relevant option for your platform. This will create a basic launch configuration.

Configure launch.json: Here’s a sample configuration you can use:

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "CMake: Debug",
            "type": "cppdbg",
            "request": "launch",
            "program": "${workspaceFolder}/build/your_executable", // Change to your executable path
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceFolder}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb", // or "lldb" based on your setup
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                }
            ],
            "preLaunchTask": "build" // Optional: refers to build task
        }
    ]
}

Setting Breakpoints

To set a breakpoint, simply click in the gutter (the left margin) next to the line number where you want the execution to pause.

Start Debugging

Now that your launch.json is set up, click on the green play button in the Debug view or press F5 to start debugging. The debugger will launch your application, and execution will pause at any breakpoints you have set.

Tips for Effective Debugging

Use the Debug Console: You can evaluate expressions and inspect variables during debugging.
Watch Variables: Add variables to the Watch panel to monitor their values in real time.
Step Through Code: Use the step over, step into, and step out commands to navigate your code line-by-line.
Inspect Call Stack: Use the Call Stack panel to see the sequence of function calls leading to the current execution point.

Conclusion

Debugging CMake projects in Visual Studio Code using the CMake Tools and C/C++ extensions can significantly enhance your development workflow. With the right configuration, you can easily build, run, and debug your applications directly from the editor. Remember to utilize breakpoints and the debugging tools available to streamline your debugging process. Happy coding!