%general-entities; ]> On the ARM architecture, there are two major ABI types to choose from: EABI and OABI. There is also a Thumb ABI and an Intel IWMMX specific ABI. The EABI (Embedded ABI) is newer and supports additional features, faster software floating point operations, and Thumb interworking, but is only compatible with ARMv4t and newer cores. The EABI has sub-ABIs of: aapcs-linux and aapcs. aapcs-linux has standard Linux 4 byte enums while aapcs has variable length enums. The OABI (old ABI) is called apcs-gnu and supports ARMv4 and older cores. ABI BUILD=Value Note apcs-gnu apcs-gnu Legacy ABI, arm4 and older atpcs atpcs Thumb ABI aapcs aapcs EABI w/ variable size enums aapcs-linux aapcs-linux EABI w/ standard Linux 32 bit (int) enums iwmmxt iwmmxt Supports Intel XScale MMX extensions