39 lines
1.1 KiB
C++
39 lines
1.1 KiB
C++
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class Shape {
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public:
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virtual double Area() { return 1.0; }
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virtual double Perimeter() { return 1.0; }
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// Note that destructors generate two entries in the vtable: base object
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// destructor and deleting destructor.
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virtual ~Shape() = default;
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};
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class Rectangle : public Shape {
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public:
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~Rectangle() override = default;
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double Area() override { return 2.0; }
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double Perimeter() override { return 2.0; }
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virtual void RectangleOnly() {}
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// This *shouldn't* show up in the vtable.
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void RectangleSpecific() { return; }
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};
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// Make a class that looks like it would be virtual because the first ivar is
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// a virtual class and if we inspect memory at the address of this class it
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// would appear to be a virtual class. We need to make sure we don't get a
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// valid vtable from this object.
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class NotVirtual {
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Rectangle m_rect;
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public:
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NotVirtual() = default;
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};
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int main(int argc, const char **argv) {
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Shape shape;
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Rectangle rect;
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Shape *shape_ptr = ▭
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Shape &shape_ref = shape;
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shape_ptr = &shape; // Shape is Rectangle
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NotVirtual not_virtual; // Shape is Shape
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return 0; // At the end
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}
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