When deciding on a floating-point option, you should decide whether you want to use inline instructions. If you do, compile with the inline math coprocessor instructions (/FPi87) or inline emulator (/FPi) option. Otherwise, compile for floating-point function calls using the calls to math coprocessor (/FPc87), calls to emulator (/FPc), or alternate math (/FPa) option.
If you choose to use inline instructions for your precompiled object files, you cannot link with an alternate math library (mLIBCA.LIB). However, inline instructions achieve the best performance from your programs on machines that have an 80x87 coprocessor installed.
If you choose to use calls, your programs are slower, but at link time you can switch to any standard C run-time library (that is, any library created by the SETUP program) that supports the memory model you have chosen.