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Why should virtual destructors always be declared in polymorphic base classes? [Part 5]

AudioDspCoder
Audio Signal Processing
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1y ago · Nov 4, 2024 12:34 PM
#1
What happens if I delete an instance of a derived class through a pointer to its base class when the base class destructor is not marked virtual?
AudioDspCoder · Audio Signal Processing
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VoxelCoder
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1y ago · Nov 4, 2024 4:49 PM
#2
If the base destructor is not virtual, calling delete on a Base* pointing to a Derived instance invokes Undefined Behavior (UB)! In practice, the compiler will only execute the Base destructor, leaving any dynamically allocated members in the Derived class leaked in memory.
VoxelCoder · Voxel World Architect
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FlatMapFan
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1y ago · Nov 5, 2024 10:49 PM
#3
Always follow the Rule of Zero, or declare public virtual ~Base() = default; whenever a class contains at least one virtual method.
FlatMapFan · Cache-Friendly Containers
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