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PO(Simple C++ Concepts) Unexpected output of constructor/destructor calls
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  1. PO(Simple C++ Concepts) Unexpected output of constructor/destructor calls
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    copied!<p>Given this code:</p> <pre><code>#include &lt;iostream&gt; using namespace std; class Foo { public: Foo () { c = 'a'; cout &lt;&lt; "Foo()" &lt;&lt; endl; } Foo (char ch) { c = ch; cout &lt;&lt; "Foo(char)" &lt;&lt; endl; } ~Foo () { cout &lt;&lt; "~Foo()" &lt;&lt; endl; } private: char c; }; class Bar : public Foo { public: Bar () { cout &lt;&lt; "Bar()" &lt;&lt; endl; } Bar (char ch) : Foo(ch) { cout &lt;&lt; "Bar(char)" &lt;&lt; endl; } ~Bar () { cout &lt;&lt; "~Bar()" &lt;&lt; endl; } }; Foo f1; static Bar b1; int main() { Bar b2; { static Foo f2('c'); Foo f3; Bar b3 ('d'); } return 0; } </code></pre> <p><em>(You can just paste this directly into a compiler)</em></p> <p>The <em>first</em> part of my expected sample output is correct:</p> <pre><code>Foo() Foo() Bar() Foo() Bar() Foo(char) Foo() Foo(char) Bar(char) ~Bar() ~Foo ~Foo() ~Bar() ~Foo() ~Foo() </code></pre> <p>But I get the destructor output of the two static objects <code>static Bar b1;</code> and <code>static Foo f2('c');</code> wrong.</p> <p>The correct answer for the last part is:</p> <pre><code>~Bar() ~Foo() ~Foo() </code></pre> <p>I get:</p> <pre><code>~Foo() ~Bar() ~Foo() </code></pre> <p>This is my reasoning:</p> <p>I understand that all local objects are destructed before static objects. Of the two remaining static objects <code>static Bar b1;</code> and <code>static Foo f2('c');</code>, <code>static Foo f2('c');</code> appears <em>last</em>, so it is destructed <em>first</em>, because destructors are called in the reverse order of their creation.</p> <p>But <code>static Foo f2('c');</code> isn't destructed first, <code>static Bar b1;</code> is. Why?</p>
 

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