From the context it's obvious that 0x0 is right. AX must be 32 bits (or 64 bits) wide. https://github.com/golang/go/blob/fad2bbdc6a686a20174d2e73cf78f1659722bb

From the context it's obvious that 0x0 is right. AX must be 32 bits (or 64 bits) wide. https://github.com/golang/go/blob/fad2bbdc6a686a20174d2e73cf78f1659722bb39/src/runtime/sys_darwin_386.s https://github.com/golang/go/blob/fad2bbdc6a686a20174d2e73cf...