[gfortran,patch] -ffpe-trap library support for SysV

[FX Coudert]

> I've bootstrapped and regression tested some version
> of your -ffpe-trap patch on amd64-*-freebsd.  I didn't
> see any problems; however, I was going to go over the
> patch again after cvs is switched over to svn.

OK. I'll be happy to commit when you see fit.

> BTW: did you see my last email about SIGNAL and ALARM?
> After you fix the use of the removed must_be() function,
> I think this is okay for mainline.

I did see your mail, and was still considering whether your meant it was 
OK after I remove must_be() or if I had to submit it again. I will 
commit when svn opens.

Thanks for the reviews!

FX