X32 ABI (x32 application binary interface) is an application binary interface project and one of the interfaces of the Linux kernel. It that allows programs to take advantage of the benefits of x86-64 (larger number of CPU registers, better floating-point performance, faster position-independent code shared libraries, function parameters passed via registers, faster syscall instruction) while using 32-bit pointers and thus avoiding the overhead of 64-bit pointers.

• x32 ABI Development Website
• rpm5 tracker