Hi Terry, > Is there any sensible reason that these options seem to buried in processor-specific sections? My guess is because they are processor-specific options. > Surely the hardware floating point model varies on more than just the x86 family and friends. Yes. For example, not all 680x0 machines has a FPU. > Why isn't there a simple, global option to get a portable floating point model? Because there are different FPU facilities on different platforms that may have a different, non-portable floating-point model. > Particularly now that gfortran is becoming more popular! If the Fortran users express a desire for some Fortran level floating-point compliance to a portable floating-point model, perhaps the maintainer of the gfortran front-end tool-chain driver will add a flag to that effect. I imagine such a flag would have these guarantees: + behind the scenes, specifies the processor-specific option to insure floating-point portability + may impose severe performance penalties (one-to-two orders of magnitude) on some platforms + may cause the compile to fail if the floating-point constraint cannot be fulfilled (which is probably a good thing) > Tying the floating point model to a particular hardware feature/instruction set (SSE) seems absolutely absurd to me. It should be abstracted to a much higher level. It's a trade-off, without a doubt. Java has a facility that allows strong guarantees on floating-point fidelity. And Mathematica allows very powerful expression of symbolic and mathematical manipulation and expression. And there's always Lisp. Sincerely, --Eljay
