backport: re PR bootstrap/26998 (bootstrap failure building libdecnumber, ICE in...

backport: re PR bootstrap/26998 (bootstrap failure building libdecnumber, ICE in compare_values, tree-vrp.c:432)

2007-05-16  Richard Guenther  <rguenther@suse.de>

        Backport from mainline:
        2006-06-09  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/26998
        * tree-vrp.c (extract_range_from_unary_expr): For NEGATE_EXPR
        of signed types, only TYPE_MIN_VALUE is special, but for both,
        minimum and maximum value.  Likewise VR_ANTI_RANGE is special
        in this case, as is -fwrapv.

        * gcc.dg/torture/pr26998.c: New testcase.
        * gcc.dg/tree-ssa/vrp29.c: New testcase.

From-SVN: r124767