Yesterday's exercise asked you to predict and explain the codegen for the following fragment: Well, the codegen might go something like this: Let's use one of our fancy pictures: Just for fun, I swapped the order of Base1 and Base2. There is no requirement in the standard about the order in which storage is allocated for base classes, so ...

It was bound to happen sooner or later. I was invited to join Orkut. But before clicking Submit, I always read the fine print: their Terms of Service and their Privacy Policy. (Oh great, you have to have scripting enabled just to read their Terms of Service and Privacy Policy!) Notice, for example, the terms for changes to their terms of service: ...

First, ABBA rises to stardom in their native Sweden with Ring, Ring. They then win the Eurovision Song Contest with Waterloo, which is also recorded in English, French, German, and probably Spanish. Twenty-five years later, the English-language musical Mamma-Mia premieres in London and subsequently spreads through large portions of the world not y...

Pointers to member functions are very strange animals. Warning: The discussion that follows is specific to the way pointers to member functions are implemented by the Microsoft Visual C++ compiler. Other compilers may do things differently. Well, okay, if you only use single inheritance, then pointers to member functions are just a pointer to ...

Yesterday we learned about the layout of COM objects and I hinted at "adjustor thunks". If you find yourself debugging in disassembly, you'll sometimes find strange little functions called "adjustor thunks". Let's take another look at the object we laid out last time: In the diagram, p is the pointer returned when the IPersist interface is n...

The Win32 COM calling convention specifies the layout of the virtual method table (vtable) of an object. If a language/compiler wants to support COM, it must lay out its object in the specified manner so other components can use it. It is no coincidence that the Win32 COM object layout matches closely the C++ object layout. Even though COM was o...

Answers to yesterday's exercises: What happens if you allocate with scalar "new" and free with vector "delete[]"? The scalar "new" will allocate a single object with no hidden counter. The vector "delete[]" will look for the hidden counter, which isn't there, so it will either crash (accessing nonexistent memory) or grab a random number and a...

The Glass Engine is an interactive guide to the music of Philip Glass, organized by... um... at least they're organized. By something. Bizarre yet oddly compelling. (Perhaps if we ask nicely, we can get Marc Miller to tell the story of the time he actually met Philip Glass...) In a similar vein, a friend of mine directed me to Ishkur's Guide to Ele...

In a previous entry I alluded to the problems that can occur if you mismatch scalar "new" with vector "delete[]" or vice versa. There is a nice description of C++ memory management in C++ Gotchas: Avoiding Common Problems in Coding and Design on www.informit.com, and I encourage you to read at least the section titled Failure to Distinguish Sca...

Lockergnome tipped people off to this page which talks (among other things) about adding "Copy To" to the context menu. I considered adding this tweak to Tweak UI but ultimately decided against. Here's why: The "Copy to Folder" and "Move to Folder" options weren't designed to be on the context menu. They were only meant to be placed in Explorer's...