floating points and divisions by zero.

[Craig Burley]

>I have implementations of the link/runtime technique suggested
>there for various targets.  I think it would be useful for something
>similar (or better) to be available through a gcc link-time option,
>however Craig had an objection to this sort of thing in the g77 driver
>that I can't now remember but perhaps he can.

Not *quite* sure I can, but generally I've tried to avoid adding
anything to what the g77 driver passes downstream unless it's
really clear that all systems can handle such things.  For example,
some systems need (or needed at one time) `-lf2c -lc -lm' instead
of just `-lf2c -lm' to be appended to properly link in the run-time
library (libf2c.a), but when we tried that, it broke on some systems
with no libc.a!  And the g77 driver doesn't know about build, host,
or target system as currently incarnated.

In any case, I suspect this situation is one of *many* involving
g77 (and gcc) where we *want* to do The Right Thing, but for mostly
good reasons (and some bad, e.g. plain ol' fear ;-), hesitate to do
it until we can be sure we do it The Right Way.  I'd say that using
command-driver command-line options to implement the desired
floating-point behavior is The Wrong Way to do what is probably
The Right Thing, but I haven't looked into the issue closely myself.

        tq vm, (burley)