[PATCH] Fix PR30951, missed folding of x == x + 1

[Joseph S. Myers]

On Sat, 24 Feb 2007, Richard Guenther wrote:

> This fixes PR30951 which I noticed while working on the fix for 30364.  We
> can fold == and != comparisons regardless of overflow behavior for
> X +- CST op X.

With -ftrapv, is the trap still preserved if X +- CST overflows?

-- 
Joseph S. Myers
joseph@codesourcery.com