Performance of 32-bit integers in a 64-bit environment (C++)

Question

We\'ve started compiling both 32- and 64-bit versions of some of our applications. One of the guys on my project is encouraging us to switch all of our 32-bit integers to their

Answer 1

The idea that using a 64bit integer vs. a 32bit integer will speed things up is a myth. The more important thing in your code is to use the appropriate types. For instance, when referring to the size of an array or data structure, use a size_t because that's what a size_t is supposed to represent. If you're storing some piece of data, then use an int and not a size_t because that's what an int is meant to describe.

Don't just change everything to size_t because it will "automatically become 64bit" this will result in probably no improvement whatsoever. It will cause larger memory overhead which will probably cause the application to slow down due to cache misses because of the larger memory space. It will also quite possibly cause unexpected bugs.