The Old New Thing

Why does the debugger show me the wrong virtual function?

March 23, 2005 Mar 23, 2005 03/23/05

Raymond Chen

Pointers to virtual functions all look basically the same and therefore, as we learned last time, all end up merged into a single function. Here's a contrived example: class Class1 { public: virtual int f1() { return 0; } virtual int f2() { return 1; } }; class Class2 { public: virtual int g1() { return 2; } virtual int g2() { return 3...

Why does the debugger show me the wrong function?

March 22, 2005 Mar 22, 2005 03/22/05

Raymond Chen

Often you'll be minding your own business debugging some code, and you decide to step into one function and the debugger shows that you're in some other function. How did that happen? class Class1 { public: int *GetQ() { return q; } private: int *p; int *q; }; class Class2 { public: virtual int GetValue() { return value; } private: int...

Your exception handler can encounter an exception

March 17, 2005 Mar 17, 2005 03/17/05

Raymond Chen

Consider the following code, written in C# just for kicks; the problem is generic to any environment that supports exception handling. void ObliterateDocument() { try { try { document.DestroyAll(); } finally { document.Close(); document.DestroyExtensions(); document.DestroyPlugins(); } } finally { document.Destroy...