Who's afraid of a big bad optimizing compiler?

Our increasingly aggressive modern compilers produce increasingly surprising code optimizations. Some of these optimizations might be especially surprising to developers who assume that each plain C-language load or store will always result in an assembly-language load or store. Although this article is written for Linux kernel developers, many of these scenarios also apply to other concurrent code bases, keeping in mind that "concurrent code bases" also includes single-threaded code bases that use interrupts or signals.

Full Story (comments: 78)