When Is Manual Memory Management Still Justified in Modern C ?

Modern C : Rethinking the Use of Manual Memory Management

In recent years, the C community has witnessed a shift away from traditional memory management techniques such as new, delete, raw pointers, and C-style arrays. With the introduction of smart pointers and the C standard library's container facilities, these constructs have largely been replaced in most programming scenarios. However, there remain discussions regarding the validity of using them in modern C code.

Are There Valid Use Cases for Manual Memory Management?

Except in exceptional circumstances, smart pointers and standard containers effectively handle dynamic memory management. However, there exist rare cases where direct use of new and delete may be advantageous. One such scenario occurs when ownership semantics should not reside locally.

Consider, for example, designing a linked list with forward unique pointers. At destruction time, deleting each node individually could result in a stack overflow. Instead, ownership can be managed at a higher level, such as at the container itself, allowing for more controlled memory cleanup.

Other scenarios include complex ownership lifetimes not easily accommodated by containers or smart pointers, where it becomes challenging to determine correct ownership semantics. While these cases are uncommon, they do exist.

Are Raw Arrays Still Useful?

Raw C-style fixed-size arrays have also been largely supplanted by std::array. The latter provides consistent assignment, copying, and referencing capabilities. Nevertheless, there are isolated scenarios where a raw array may be preferred. One such instance is when interfacing with external libraries that expose raw pointers or C-style arrays. For these cases, using std::array may require explicit casting or conversion operations, which can be error-prone.

Conclusion

While manual memory management using new, delete, raw pointers, and C-style arrays is generally discouraged in modern C , there remain rare and specialized use cases where their direct use is justified. These include complex ownership semantics and interfacing with third-party libraries that use non-standard memory management techniques.

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