signed is undefined and has been since 1992 (in GCC)

[Andrew Pinski]

The first change in GCC which changed signed overflow/wrapping to be 
undefined
was added back in 1992 in loop.c.  The next change was in 1999 with the
addition of simplify-rtx.c.  Why are we talking about this now, instead 
of back
when they were added?  (note both of these changes were before fwrapv 
can into
play).

-- Pinski