fold-const.c (const_binop, [...]): Do not set TREE_CONSTANT_OVERFLOW.

2009-03-30  Paolo Bonzini  <bonzini@gnu.org>

        * fold-const.c (const_binop, fold_convert_const_real_from_fixed,
        fold_convert_const_fixed_from_fixed,
        fold_convert_const_fixed_from_int,
        fold_convert_const_fixed_from_real, fold_negate_const): Do not
        set TREE_CONSTANT_OVERFLOW.
        * tree.def: Remove mention of TREE_CONSTANT_OVERFLOW.
        * tree.h (TREE_CONSTANT_OVERFLOW): Delete.

From-SVN: r145281