Fixed or forbidden register was spilled

[Jeffrey A Law]

  In message < 199811262241.XAA08179@ignucius.axis.se >you write:
  > 
  > > From: Bill Currie <bcurrie@tssc.co.nz>
  > > Date: Thu Nov 26 22:18:45 CET 1998
  > 
  > [Removed example of correct FD_ZERO asm using '&' constraint
  > modifier on output]
  > 
  > > I'm curious: what about the `+' modifier?  Is it more, or less,
  > > appropriate than `=&', or is it only a matter of asthetics? 
  > 
  > It was not valid for gcc-2.7.2, which might be an issue for
  > packages like glibc.
"+" is not valid in an asm for any version of egcs or gcc.  The manuals
explicitly say not to use it for asms.

jeff