[geofft]

This post is about i386 / x86_32. What you're referring to is "x32," a different thing entirely, which uses the x86-64 instruction set. You can tell this post is not about "x32" because it talks about "segments, gates, and other delights from the i386 era," which don't exist on the x86-64 architecture regardless of how long your pointers are, and it says things are "fine on a 64-bit kernel" (x32 uses a 64-bit kernel, it's a userspace ABI only).