CLion 2019.2 Help

Debug

Start a debugging session

  1. Configure the Run/Debug Configurations profile (Run | Edit Configurations). For more information, see Configuring Debugger Options.

  2. Choose the desired CMake profile.

  3. Define a run/debug configuration for the application to be debugged.

  4. Create a breakpoint.

  5. Click the Debug <configuration_name> button Debug. Learn more from Starting the Debugger Session.

After you've started a debug session, the Debug icon that marks the Debug tool window toggles to the Active Debugger icon to indicate that the debug process is active.

Debug

After you have configured a run configuration for your project, you can launch it in debug mode by pressing Shift+F9.

In the Debug tool window you can see the list of frames and threads with their states, variables and watches. When you select a frame, you see the variables corresponding to the selected frame.

Breakpoints

Customize breakpoint settings

To customize breakpoint settings, press Ctrl+Shift+F8. To see all breakpoints in the project (with additional settings), click More or press the same shortcut Ctrl+Shift+F8 again.

Breakpoint properties

Do not suspend code execution

Use action breakpoints to evaluate a variable at a particular line of code without suspending code execution. To create an action breakpoint, click the gutter while pressing Shift.

Adding an action breakpoint

Create a temporary breakpoint

To create a breakpoint that stops only once, click the left gutter while holding Shift+Alt. For more information, refer to the section Breakpoints.

cl temp breakpoint

Disable breakpoints

To disable a breakpoint, click the breakpoint while pressing Alt. Refer to the section Breakpoints for details.

Debugger session

Run to cursor

  1. Create a breakpoint.

  2. Run a debugging session. To run a debugging session, click the Run Application icon (the Run Application icon) in the gutter area and select Debug <configuration_name>.

To stop code execution at the cursor position without adding another breakpoint, click the Run to cursor icon (the Run to cursor icon) or press Alt+F9. Alternatively, you can click the line number in the gutter area.

Run to cursor

The icon Run to Cursor is described in the toolbar reference of the Debug tool window.

Evaluate expression

In the debug mode, you can evaluate an expression by pressing Alt+F8.

cl evalexpr panelbutton

The Evaluate dialog supports code completion.

To see how the behavior of various function calls changes during your debugging session, set custom watches. You can read more about watches in Add, Edit and Remove Watches.

cl evalexpression

Refer to the section Evaluate Expressions for details.

Configuring debugger settings

To change debugger settings, click File | Settings. In the Settings menu, click Build, Execution, Deployment | Debugger.

Useful debugger shortcuts

Action

Hotkey

Toggle breakpointCtrl+F8
Resume programF9
Step overF8
Step intoF7

Stop

Ctrl+F2
View breakpoint details/all breakpointsCtrl+Shift+F8

Debug code at caret

Shift+F9 (within the main method), or Shift+Alt+F9

Remote debug

The final thing you definitely should know about debugging in CLion is Remote debug. Remote debug means attaching debugger to a process which is already running on a specific port on your or any other’s host. This way you can attach the debugger to your application server which is running standalone.

To create a remote configuration, go to Edit configurations and add a new GDB Remote Debug configuration. Make sure to specify the correct host and port before running this configuration.

Last modified: 8 November 2019