## Do Smart Pointers in C Really Impact Performance?

Smart Pointer Overhead in C

Smart pointers in C , such as std::shared_ptr and std::unique_ptr, provide automatic memory management, reducing the risk of memory leaks and dangling pointers. However, it is often questioned whether their use introduces additional performance overhead compared to traditional pointers.

Memory Overhead

• std::unique_ptr: This smart pointer only incurs memory overhead if a non-trivial deleter is provided.
• std::shared_ptr: Always has a small memory overhead due to its reference counter.

Time Overhead

• std::unique_ptr: Constructor (if custom deleter requires copying or pointer is null-initialized) and destructor (to destroy owned object).
• std::shared_ptr: Constructor (reference counter creation), destructor (reference counter decrement and possible object destruction), and assignment operator (reference counter increment). Note that increments/decrements are atomic for thread safety, introducing some additional overhead.

Dereferencing

Both smart and normal pointers have no time overhead in dereferencing (obtaining the reference to the owned object).

Impact on Performance

While smart pointers introduce some overhead, it is typically not significant. However, continuous creation and destruction of smart pointers can lead to performance degradation.

In summary, the overhead of smart pointers compared to normal pointers in C 11 is minimal, particularly for commonly used operations like dereferencing.

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