What's New in CLion

CLion 2019.3 speeds up code completion by adding a Clangd-based provider, eliminates various UI freezes, and introduces many other performance improvements. It enhances the integration with CMake, adding Ninja generator support among other things, and brings code coverage and WSL2 support. The debugger support has been significantly improved in lots of ways. And finally, support for C++20's Concepts has made it in including refactoring, navigation, and code completion.

2019.3 (Nov 28)

Better IDE Performance

This release of CLion is quality-targeted with lots of performance improvements made throughout. The key enhancements affect code completion, the Rename refactoring, optimizations for the Building/Updating symbols step, and the elimination of UI freezes. Learn more.

Clangd-based code completion

Clangd is now added to the list of code completion providers in CLion, which helped speed up the time for the first results to appear on many projects significantly. Check out the detailed performance metrics we’ve gathered.


Quicker Rename refactoring

The Rename refactoring in CLion is really powerful as it can rename not only code usages but also usages in string literals and comments. If you still want to rename only code usages, it’s now much faster as it can ask you to make this decision before the actual search. (To use this, turn off Settings | Editor | General | Refactorings | Enable in-place mode.)

Ninja and other generators in CMake

Ninja Gen

Support for the new CMake File API lets CLion 2019.3 enable various CMake generators (requires CMake 3.15 or higher). Previously, only Makefiles were supported, now users can select Ninja, Xcode, Visual Studio, etc.

This works for all platforms, in remote mode, and with WSL.

Learn more

CMake defaults

CMake Defaults

To simplify the configuration process for your new CLion projects, you can now configure one or more default CMake Profiles, which will be used for all your new projects. Use File | Other Settings | Settings for New Projects…

Other CMake support improvements include:

  • It’s now possible to reload CMake valid configurations even if some others are failing.
  • CMake 3.15 is bundled in CLion 2019.3.
  • If your compiler doesn’t support the -fpch-preprocess flag, your project will still be successfully loaded in CLion 2019.3. Check out the details in this blog post.


Remote GDB Server

If you want to debug an executable on a remote machine from a locally running CLion, you can now use the Remote GDB Server configuration. CLion will upload the executable and launch your program under gdbserver, so there’s no need to do it manually anymore. Learn more.

remote gdb

LLDB 9 and better pretty printers

In CLion 2019.3, the bundled LLDB on macOS and Linux was updated to v9.0. Besides this, a major clean-up was performed in the bundled LLDB pretty printers, fixing a whole set of related issues. See how libc++ and libstdcxx are now handled on macOS and Linux.

Read .gdbinit/.lldbinit from the project root

If you want to customize the GDB/LLDB debugger behavior on a particular project, you can now do so in CLion, as it supports reading the settings file from the project root directory.

Note that to enable this behavior, you have to explicitly allow it in your home file. See how to do this for LLDB and GDB.


C++20’s Concepts

One of the biggest features coming in C++20 is definitely Concepts. By collaborating with the author of Concepts support in Clang, we’ve brought Concepts to CLion 2019.3. The support covers not only code parsing and highlighting (which is done by the Clangd-based language engine), but also comes with:

  • The Unused Concept inspection.
  • Code completion including completion for types constrained by std::is_base_of<MyBase, T> and std::is_same<Other, T>.
  • The Rename refactoring.
  • Go to Definition and Find Usages.

Learn more.

Code Analysis

virtual call

Virtual functions called from constructors / destructors

To prevent situations where virtual functions access resources that are not yet initialized or have already been destroyed, CLion gets a new inspection which detects virtual functions called from constructors or destructors.

Spelling in Doxygen

Spell Checker

The Spell Checker is useful for keeping the code accurate and readable. CLion has had it for C/C++ code for a long time. In v2019.3 we’ve enabled it in CMake and Doxygen comments.

Code Coverage


If you’ve ever asked the question, “Was this statement executed during the configuration run?”, that means you are looking for statements coverage measuring for your code. CLion 2019.3 has it thanks to the integration with llvm-cov/gcov tools.

You can get it for unit tests run or a regular configuration run. The results are available in the Coverage tool window or via a color indication in the editor’s left gutter.

Learn more.


Go to Header/Source

Go to Header/Source action

A new action to switch between header/source files was added. It’s more accurate and quicker for many C/C++ cases than Go to Related Symbol.

If multiple options to navigate to are identified within 500 ms, CLion shows an interactive popup where new items are added and you can select where you want to navigate to.

There is also a built-in mechanism to remap the shortcut from Go to Related Symbol to this new action, should you want to.

Learn more.

Microsoft formatting and naming rules

In CLion, you can configure a set of formatting options and naming convention rules. Or, alternatively, you can inherit these settings from one of the predefined styles. In CLion 2019.3, we’ve added Microsoft’s predefined formatting and naming style to the list.



Windows Subsystem for Linux provides a convenient way to develop on Windows for Linux target platform. CLion natively supports the WSL environment and now comes with support for WSL version 2. The configuration process in CLion is completely the same for WSL v1 and WSL v2!

Learn more.

Rust plugin update


One of the biggest updates for IntelliJ Rust is the initial support of cfg attributes. Now, the conditionally disabled blocks are grayed-out and excluded from resolve and code analysis. Among the supported cfg options are unix, windows, and target_os.

The widely used quick-fix, Auto-import for unresolved symbols, now works automatically when you call Implement members, Specify type explicitly, Add remaining patterns, and other code generation actions.

Other changes include Code Coverage for your Rust code, which has been a part of the plugin for a few releases already, handy interactive inlays for type hints, and include! macro support.

Other changes

  • VCS support: the Clone dialog (VCS | Get from Version control) was reworked. Now you can log in from the dialog, or if you’re already logged in, the IDE will instantly preview the lists of all repositories grouped by accounts or organizations.
  • Some UI updates:
    • A new option to make the scrollbars more visible was added – Settings | Appearance & Behavior | Appearance | Use contrast scrollbars.
    • A lot of UI issues were addressed in the updated JetBrains Runtime.
2019.2 (Jul 24)

Embedded Development

Debug with GDB Server

On-Chip debugging with GDB Server

If it’s possible to debug on the microcontroller of your choice with a GDB Server, you can now do it from CLion using a special Embedded GDB Server Run/Debug configuration. It covers OpenOCD, ST-Link GDB Servers, Segger J-Link GDB Server, QEMU, and many other specific GDB Servers.

Create a configuration, providing a path to GDB Server, arguments to run the server, and other appropriate settings, and you are all set and ready to debug on-chip from CLion!


Peripheral View for ARM Devices

When debugging on-chip, it’s crucial to have the ability to view the peripherals. In CLion, this view is now available for two types of Run/Debug configurations: Embedded GDB Server and OpenOCD Download & Run. In both cases, a Peripherals tab appears in the debug tool window when you start debugging. Load the appropriate .svd file for your board and select the active peripherals you need to see.

Learn more


Line breakpoints

Pending, resolved, and invalid breakpoints

CLion 2019.2 now distinguishes three types of line breakpoints:

  • Pending: Line breakpoint is out of the debugging session, which means the session hasn’t started yet or the corresponding shared library hasn’t been loaded yet).
  • Resolved: Line breakpoint is successfully resolved by GDB or LLDB using the provided debug symbols, and can be hit during the execution.
  • Invalid: Line breakpoint can’t be resolved by GDB or LLDB and can never be hit.

The types are detected automatically on the fly and the breakpoint icons are updated accordingly.

Debugger commands completion

Completion for GDB/LLDB commands

If you prefer the command line interface of GDB/LLDB and use the debugger console available in the debug tool window, you will benefit from completion for GDB/LLDB commands. Use Tab or Ctrl+Space to invoke it.

This completion is powered by GDB or LLDB, respectively; CLion simply gives you access to the suggestions.

MSVC debugger

An experimental debugger for the MSVC toolchain

If you use the Microsoft Visual C++ toolchain in CLion, now you can try a new experimental debugger.

It’s implemented by the JetBrains team on top of LLDB and is bundled into CLion. To enable bundled support for native visualizers, use Settings | Build, Execution, Deployment | Debugger Data Views | Enable NatVis renderers for LLDB.

An experimental debugger is available when turned on explicitly: call up the Maintenance dialog (Shift+Ctrl+Alt+/) | Experimental features, and select cidr.debugger.lldb.windows to control it.

Learn more

Memory View

When debugging your application, you can easily review the memory behind a pointer: in the Variables view of the debug tool window, press Ctrl+Enter on a pointer to invoke the Memory View. In 2019.2, we’ve updated the Memory View to make it even more useful.

Go to address

Go to address

Navigate to a particular address in memory from the Memory View. Use the hex value representing an address, a pointer variable, or call the address (&) of any variable you are interested in.

Code completion will assist you with the known symbols.

ASCII view


If you are interested in the ASCII memory format, you’ll find the ASCII view in the column on the right of the Memory View useful.

Parameter hints

Parameter Name hints

Thanks to parameter name hints in v2019.2, you can avoid switching to the function signature while exploring a function call. This in turn should help increase the code readability.

For function calls, lambdas, constructors, initializer lists, and macro expressions, CLion shows the names of the parameters for the passed arguments. This works if an argument is a literal or an expression with more than one operand.

Learn more

Code analysis

Unused Include

Unused Includes

The ‘unused includes’ check is back and completely reimplemented on top of the Clangd-based engine. It suggests 3 detection strategies: a conservative one, an aggressive one, and the default one (Detect not directly used) which is the closest to the “Include What You Use” principle.

Learn more

Clang-Tidy update

The Clang-Tidy bundled binary was updated to the newest version, which brings a set of new checks to CLion. This includes some new abseil-* checks, a few from the clang-analyzer-* group, several new modernize-* checks, and more.

Code assistance for .clang-format files

Since v2019.1, CLion has support for ClangFormat as an alternative formatter tool. Now, if you have customized your .clang-format config files in the project, you can benefit from code assistance when you update them. Learn more

Quick Doc

Quick Documentation

To learn about any particular option, call the Quick Documentation popup (Ctrl+Q) and read the original documentation with samples.

ClangFormat config inspection

Schema validation inspection

CLion validates the content of your .clang-format config file against the built-in JSON schema. If the option’s value doesn’t match the allowed value set, a warning will be shown.

ClangFormat completion

Code completion

When customizing the .clang-format config file, you can benefit from code completion working for both options and their values.

ClangFormat doc

Options description in completion

Code completion popup for option names also includes a short description of the option, so you can quickly check it while typing the option name.

Naming convention

Naming settings

New settings

The naming convention settings (Settings | Editor | Code Style | C/C++ | Naming Convention) were reworked to provide better flexibility and more opportunities. New settings like Visibility (Public, Private, or Protected) and Specifier (Const or Static) were added. We’ve also updated the rules to address several kinds of entities at once.

It’s possible to work with the new UI without using the mouse.

Leading Snake Case

Leading snake case

As requested by CLion users, a new style – Leading_snake_case, which capitalizes only the first letter in the snake_case name, leaving the rest in lower case – is now available, along with the somewhat similar Upper_Snake_Case style and others.

Shell Script plugin

Shell Script plugin

If you need to edit shell scripts while you are working on your C++ project, you can do this with CLion as it now bundles the Shell Script plugin.

You can benefit from code highlighting, word and path completion, and even textual Rename.

Syntax highlighting for new languages

Ruby syntax highlighting

CLion provides bundled profound support not only for C and C++, but also for Python, JavaScript, XML, and more, as well as providing plugins for Rust, Swift, and Kotlin/Native.

Have code in your project in other languages, such as PHP, Ruby, or C#? You’ll be happy to learn that syntax highlighting is now available in CLion for over 20 different programming languages!

Learn more

VCS: Commit from the Local Changes

Commit from Local Changes

You can now commit directly from Local Changes tab. Just enable the “Commit from the Local Changes without showing a dialog” option at Settings | Version Control | Commit Dialog.

Use the Commit shortcut (Ctrl+K) and the IDE will select the modified files for the commit and focus on the Commit message field in the Local Changes tab of the Version Control tool window.

Learn more about other VCS changes

Performance improvements

There is some huge ongoing work in CLion to improve the IDE’s performance such as indexing, responsiveness, and elimination of freezes, among others. Part of this work is already included in v2019.2:

  • The in-place Rename refactoring was reworked to eliminate lags and freezes.
  • The performance of code completion for qualified expressions in the editor has been significantly improved.
  • Collecting compiler information and thus loading the CMake step in remote cases was accelerated by reducing the number of I/O operations.
  • CLion now warns you when Windows Defender is affecting the build performance and is able to automatically exclude directories from real-time scanning.

Rust plugin update

Rust plugin

Another huge update for the Rust plugin brings a new experimental macro expansion engine. You can turn it on in Settings | Languages & Frameworks | Rust | Expand declarative macros.

This engine provides you with code insight features such as highlighting, name resolution, and completion for generated modules and methods from impl blocks. Besides this, it enables navigation in the macro calls.

Other changes include a Duplicate code fragments inspection for Rust, and other new quick-fixes and inspections.

2019.1 (Mar 27)

Embedded Development

STM32CubeMX integration

STM32CubeMX integration

If you develop for STMicroelectronics boards, you’ll be happy to know that CLion now integrates with STM32CubeMX:

  • CLion can create a new .ioc project or open an existing one, and generate a CMake file to correctly work with it.
  • You can start STM32CubeMX any time directly from CLion to update board settings and generate code.
  • CLion reminds you to select a board config and suggests a list of options in the UI.
OpenOCD support

OpenOCD support

Debugging with the Open On-Chip Debugger is now supported by CLion. Use the new Run/Debug configuration template, ‘OpenOCD Download and Run’ to debug on your microcontroller.

If you work with a STM32CubeMX project in CLion, an OpenOCD Run/Debug configuration will be created for you automatically.

Learn more about STM32CubeMX & OpenOCD integration


The ClangFormat tool is widely used in the C/C++ world and even regarded as a standard by many developers. Its config files can be found in many projects, and especially in open source software. And it’s now supported in CLion! Learn more.

ClangFormat across all IDE actions

ClangFormat across all IDE actions

CLion 2019.1 adds ClangFormat as an alternative code formatter. Turn it on for your current project or all projects in CLion and let CLion use it to format your code as you:

  • Type in the editor or paste code
  • Call the Reformat Code action
  • Reformat as a pre-commit hook
  • Generate boilerplate code
  • Refactor code
  • Apply quick-fixes or intention actions
Working with .clang-format config

Working with .clang-format config

CLion detects .clang-format config files in your project and will suggest switching to ClangFormat. If there are multiple config files, you can identify which one is used in a particular file opened in the editor by selecting “View ClangFormat options for <file name>” from the toolbar switcher.

Don’t have a config file? No problem – CLion will simply default to LLVM style.

Naming conventions

Setting naming in CLion

Setting naming in CLion

CLion now respects the naming scheme you provide. The selected settings will be used when:

  • Autocompleting code
  • Generating code
  • Refactoring code
  • Applying quick-fixes

You can configure the style manually in Settings | Editor | Code Style | C/C++ | Naming Convention or select naming from the predefined scheme.

Inconsistent naming inspection

Inconsistent naming inspection

CLion can help enforce the selected naming convention in the editor. Simply turn on the Inconsistent Naming inspection, and CLion will highlight problematic names and suggest a quick-fix to replace all usages with a more accurate name.

Header Guard style

Header Guard style

In Settings | Editor | Code Style | C/C++ | Naming Convention, you can configure the style for Header Guards to be used when creating a new header file.

You can update this Velocity template or select a style from one of the predefined schemes.

C++ support

Code highlighting and quick-fixes with Clangd

Code highlighting and quick-fixes with Clangd

To improve the editor performance, code highlighting and quick-fixes are now implemented on top of the complementary Clangd-based language engine (and are enabled by default along with the engine).

For quick-fixes, the location of the quick-fix is calculated in Clangd, while the fix itself is provided by CLion.

Error messages powered by Clang

Error messages powered by Clang

For some time now, we have been leveraging the Clangd-based language engine to annotate code errors and warnings in the editor. In v2019.1, CLion gets improved and more detailed error messages powered by Clang.

A practically useful example of this is debugging a failed overload resolution in your C++ code.

Improved Rename refactoring

Improved Rename refactoring

We’ve improved the Rename refactoring for files:

  • When you do a file rename, CLion asks if you’d like to also rename an associated class/struct, and the other way around.
  • When the header file is renamed, the header guards are updated accordingly.
Improved Extract refactoring

Improved Extract refactoring

The Extract refactoring is now more accurate and:

  • Respects type aliases and doesn’t expand on static members
  • Respects std:: namespace qualifier
  • Respects template specialization and template parameters
Member function can be static

Member function can be static

This new inspection reports member functions that can be marked as static. It works on top of the Clangd-based language engine and analyzes the method body, trying to check if it depends on this or not.


Disassembly View

Disassembly View

Disassembly View is now available for LLDB in addition to GDB backend. We’ve also improved the view in general so that now it shows information divided by function.

As before, Disassembly View works when you use Force Step Into (Shift+Alt+F7) on a function with no source code.

Mute Variables

Mute Variables

To get a better stepping performance, or if you need to watch the variables only occasionally, you can now explicitly Mute Variables. A general per-IDE switch will stop the variable calculation, and each variable in the variables view gets a Load option which you can apply as needed.

Learn more

Memory View

Memory View

Memory View dumps the memory behind the pointer in the Debug mode. To invoke it, select a pointer variable in the debugger’s variables view and press Ctrl+Enter.

During stepping, if you have Memory View opened, CLion will highlight the memory changes that take place in the selected memory piece.

Custom Build and Run

Custom Build Targets

Custom Build Targets

Build-system independent Build Targets (Settings | Build, Execution, Deployment | Custom Build Targets) allow you to add custom targets and configure any tools to be used for Building/Cleaning the target.

The most typical use case is a compilation database project, which lacks the information about building the whole project.

Custom Run/Debug Configurations

Custom Run/Debug Configurations

To run and debug Custom Targets from CLion, create a corresponding Run/Debug configuration by using the Custom Build Application template (Run | Edit Configurations…).

The debugger will be taken from the Toolchain setting of the Custom Build Target.

Injected languages

Injected languages

String literals with pieces of code in other languages can now be treated accordingly. To temporarily inject a language, press Alt+Enter, apply the intention “Inject language or reference”, and select the appropriate language. For example, SQL strings, HTML code, or Regular Expressions.

Based on the language chosen, CLion will provide code highlighting and language-specific intentions and actions.

Custom color themes

Brighten up Your IDE

Tired of Black and White themes in CLion? Tweak literally every color in your IDE, from icons to radio buttons and arrows.

Each theme is actually a theme plugin that you can download directly from our plugin repository. Or, if you feel up to it, create your own theme plugin using the DevKit and modify CLion’s appearance via the JSON file.

Learn more

Recent locations

Recent locations

The Recent Locations Popup (Shift+Ctrl+E) lists all the locations that you’ve visited in a chronological order so that you can easily go back and find things.

Use instant search to filter the locations by file name or code snippet included. Or, switch to showing changed locations only.

Other improvements

  • The process of building CLion’s plugins was simplified by publishing CLion as a Maven dependency to be used by gradle-intellij-plugin (since version 0.4.2). Learn more
  • The bundled CMake is updated to 3.13, the bundled LLDB is updated to 7.0.1, and the latest supported Cygwin is now 3.0.
  • IPv6 is now supported to help you use Remote Development mode in CLion. Learn more
  • The Rust plugin received a massive update: it suggests out-of-scope items in completion and auto-import, as well as supports Rust language injection into code snippets in doc comments. Besides, profiler tools (like DTrace or Perf) are now supported for Rust.