Should You Set Pointers to NULL in Destructors?

Setting Pointers to NULL in Destructors: Is It Worth It?

Introduction
When working with raw pointers, it's often customary to consider setting them to NULL in the class destructor after deallocating their associated memory. However, the question arises: is this practice truly beneficial, or is it merely an unnecessary step?

Analysis
While setting pointers to NULL in destructors may seem like a sound practice, it's generally discouraged for several reasons:

Avoids Potential Debug Build Issues:
Setting pointers to NULL in debug builds can conceal underlying bugs. A pointer set to NULL in a debug build may indicate an issue in release builds, where the pointer would remain uninitialized. This discrepancy can make debugging more difficult and potentially cause hidden problems.

Uses a Different Debugging Approach:
Rather than setting pointers to NULL, a more effective debugging approach is to set them to a known bad pointer value. This allows for the detection of potential dangling references that may still access the memory even if it's been deallocated.

Provides a Clearer Understanding of Pointer State:
Leaving the pointer uninitialized in the destructor ensures that the programmer can easily distinguish between pointers that point to valid memory and those that have been released. Setting a pointer to NULL obscures this state and can lead to confusion.

Conclusion
In most cases, setting pointers to NULL in destructors is not a recommended practice. It can lead to potential debugging issues, hinder clarity on pointer state, and conceal underlying bugs. Instead, it's advisable to leave pointers uninitialized in destructors and consider alternative debugging techniques, such as setting pointers to known bad values or using debug heap managers.

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