detecting the use of fpa in executables

[attcan!utzoo!henry at uunet.uu.net]

>... you might want to tell your vendors to send you
>object files and libraries compiled with the -fswitch option...
>... code compiled with the fpa option can
>only be run on a 3/160/180/260/280 with an fpa, not on a 3/50/60 with a
>math coprocessor, which requires use of the -f68881 option, which in turn
>won't run on a 3/50 without a coprocessor, ad nauseum...

The position we've tentatively taken on this is that the 68881 is required
on any Sun 3 that wants to be part of our system, and that it being
optional on the 3/50 is just Sun being silly.  ("Oh, you want the car with
*tires*; those are extra-cost options!")

It's kind of unfortunate that the FPA is so very different from the 68881.
I'm told that there was a faction within Sun that wanted to see the FPA
use the same coprocessor interface as the 68881, and in other ways be
software compatible.  Unfortunately, the coprocessor interface isn't quite
as fast as the load/store scheme, and the FPA was definitely built with
benchmarks in mind.

At least the Sun 4 got this right.

	Henry Spencer at U of Toronto Zoology
	uunet!attcan!utzoo!henry henry at zoo.toronto.edu