| 1 | class Shape { |
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| 2 | public: |
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| 3 | virtual double Area() { return 1.0; } |
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| 4 | virtual double Perimeter() { return 1.0; } |
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| 5 | // Note that destructors generate two entries in the vtable: base object |
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| 6 | // destructor and deleting destructor. |
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| 7 | virtual ~Shape() = default; |
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| 8 | }; |
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| 9 | |
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| 10 | class Rectangle : public Shape { |
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| 11 | public: |
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| 12 | ~Rectangle() override = default; |
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| 13 | double Area() override { return 2.0; } |
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| 14 | double Perimeter() override { return 2.0; } |
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| 15 | virtual void RectangleOnly() {} |
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| 16 | // This *shouldn't* show up in the vtable. |
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| 17 | void RectangleSpecific() { return; } |
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| 18 | }; |
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| 19 | |
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| 20 | // Make a class that looks like it would be virtual because the first ivar is |
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| 21 | // a virtual class and if we inspect memory at the address of this class it |
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| 22 | // would appear to be a virtual class. We need to make sure we don't get a |
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| 23 | // valid vtable from this object. |
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| 24 | class NotVirtual { |
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| 25 | Rectangle m_rect; |
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| 26 | public: |
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| 27 | NotVirtual() = default; |
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| 28 | }; |
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| 29 | |
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| 30 | int main(int argc, const char **argv) { |
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| 31 | Shape shape; |
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| 32 | Rectangle rect; |
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| 33 | Shape *shape_ptr = ▭ |
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| 34 | Shape &shape_ref = shape; |
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| 35 | shape_ptr = &shape; // Shape is Rectangle |
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| 36 | NotVirtual not_virtual; // Shape is Shape |
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| 37 | return 0; // At the end |
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| 38 | } |
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| 39 | |
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