Memory management is critical in game development, and errors like double-freeing memory can lead to crashes or undefined behavior. Unreal Engine provides tools to help catch these issues during development.

What is a Double-Free memory issue?

Double-freeing occurs when the same block of memory is released more than once. This can corrupt the memory allocation system and cause severe runtime issues.

Using Unreal Engine’s -doublefreefinder command

Unreal Engine includes a built-in debugging tool to detect double-free errors. Here’s how you can use it:

1. Launch the Engine with the Debugging Option
   Start the game or editor with the -doublefreefinder command-line argument. For example: YourGame.exe -doublefreefinder
2. Attach a Debugger
   Attach a debugger like Visual Studio to your process.
3. Wait for the Trigger
   If a double-freeing event occurs, the debugger will be triggered. You’ll be able to examine the call stack and trace the issue to its source.

Preventing Double-Free issues

• Use Unreal’s smart pointers (TSharedPtr, TWeakPtr, TUniquePtr) to manage memory automatically.
• Follow Unreal’s coding guidelines for object lifecycle management.
• Regularly test with tools like -doublefreefinder during development.

By incorporating these practices, you can minimize the risk of memory management errors and maintain a stable game or editor.