What's New in CLion 2025.1

CLion Nova now correctly supports header and source files that are not included in a project and are not used during the build process. This means you get complete code analysis and code assistance functionality when working with these files, just like with regular project files.

For example, you may want to open a .cpp file that is not included in your project just to edit some code fragments. You can now do this while benefitting from all the available essential features, such as code formatting, typing assistance, code completion, and more.

The current implementation covers most uses, and we also plan to collect feedback to address some edge cases.

You can now get syntax highlighting, warnings, code completion suggestions, and other features provided by clangd when working with Objective-C source files.

Because this is still basic support, some features, such as the editor’s smart keys and refactorings, may not work. Additionally, CLion Nova may not handle Objective-C header files correctly. If you’re interested in full Objective-C support in CLion Nova, please follow or upvote CPP-37281.

CLion Nova now supports using the GoogleTest and Catch2 testing frameworks in Bazel projects.

To learn more about the basics of unit testing and how to use testing tools in CLion, read our tutorial.

Qt renderers, also known as Qt pretty printers and Qt debugging helpers, allow you to view Qt variables, such as QString, QList, and QByteArray, in a human-readable form. This makes developing and debugging applications built using the Qt framework much more convenient.

This feature is enabled by default, but to use it, you need to download the Qt renderers and specify the path to them:

1. Go to Settings | Build, Execution, Deployment | Debugger | Data Views | C/C++ | Enable Qt renderers.
2. Click Download… next to the Qt renderers field.
3. When the Download Qt Renderers window appears, click Download Qt Renderers. Once the download is complete, the path will be specified automatically.
4. Click OK.

Note that Qt renderers don’t yet work with remote and WSL toolchains.

In addition to the bundled LLDB, which is currently v19.1.3, you can now use a custom LLDB when working on macOS or Linux. This allows you to choose the version of LLDB best suited to the requirements of your project.

Go to Settings | Toolchains and select Custom LLDB executable in the Debugger field. CLion will then automatically try to find the custom LLDB installed on your system. You can also manually specify its location.

The current limitations:

• Custom LLDBs don’t yet work with the WSL, Docker, or Remote Host toolchains.
• Custom LLDBs are available for macOS and Linux but are not currently supported on Windows.

When debugging a computer vision or ML application that uses OpenCV, you can view OpenCV matrices as images. CLion 2025.1 extends this functionality, allowing you to view two-channel matrices – such as cv::Mat m(2, 3, CV_8UC2) – as images.

To view a two-channel OpenCV matrix in your code as an image, select the debugger’s Threads & Variables pane, navigate to the matrix, and click View as image.

Natvis renderers, or Natvis visualizers, allow you to define visualization rules for different data types when working with the MSVC debugger. Previously, CLion could only load .natvis files from a project directory, which wasn’t flexible enough, especially when using Git or other version control systems. Now, you can specify a custom location for your .natvis files.

Go to Settings | Build, Execution, Deployment | Debugger | Data Views | C/C++ and add an additional directory with Natvis renderers. You can learn more about working with Natvis files in the documentation.

When debugging STM32 projects, you can now use the ST-LINK debug server template, which was designed specifically for STM32 chips. It contains only the most basic and essential settings, simplifying the configuration process.

Go to Settings | Build, Execution, Deployment | Debugger | Debug Servers, click +, and select the ST-LINK template. Then, configure your debug server, device, and debugger parameters.

Note that the ST-LINK configuration option only works with:

• The ST-LINK GDB server shipped with STM32CubeCLT and STM32CubeIDE.
• ST-LINK/V2 and ST-LINK/V3 probes.
• Single and dual-core MCUs.

We’ve updated the STM32CubeMX project creation process to improve usability and extend support to a wider range of STM32 chips and projects. By using the native STM32CubeMX approach to generate CMake files, CLion ensures that project creation is fully aligned with the official STM32CubeMX workflow and toolchain.

We’ll continue to improve the STM32CubeMX New Project wizard, and your feedback is very much appreciated (CPP-42553).

You can now view and manage DTR, DSR, RTS, and CTS hardware control signals when working with the Serial Port Monitor plugin. This gives you more control over attached devices that use a serial port such as Arduino and ESP32.

To enable hardware control signals:

• In the Serial Connections tool window, navigate to the Connect tab.
• Select the desired COM port.
• Click the Show HW controls checkbox.

The control options and indicators will then appear in the COM port tab.

You can also view timestamps in the monitor output, which is useful for tracking message sequences in detail.

The bundled CMake version has been updated to v3.31.4, and includes support for CMake Presets v10. Presets are stored as JSON files and are useful when you want to specify common configuration and build options for a CMake project to share them with other users.