Intel's open-source ThreadBuildingBlocks has a template, Atomic, that offers the same functionality as .NET's Interlocked class.
Unlike gcc's Atomic built-ins, it's cross platform and doesn't depend on a particular compiler. As Nemanja Trifunovic correctly points out above, it does depend on the compare-and-swap CPU instruction provided by x86 and Itanium chips. I guess you wouldn't expect anything else from an Intel library : )
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…