cpp / expert
Snippet
Placement New for Manual Memory Management
Placement new allows you to construct an object at a pre-allocated memory address. This is critical for high-performance systems and custom allocators where heap fragmentation or allocation overhead must be avoided.
snippet.cpp
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char buffer[sizeof(MyClass)];MyClass* obj = new (buffer) MyClass(42);// Manual cleanup required:obj->~MyClass();
Breakdown
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new (buffer) MyClass(42)
Calls the constructor of MyClass using the memory provided by 'buffer' instead of the heap.
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obj->~MyClass()
Explicitly calls the destructor since 'delete' cannot be used on placement new objects.