https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71372
--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to rguent...@suse.de from comment #8)
> On Thu, 2 Jun 2016, rguenther at suse dot de wrote:
> Actually it's not a bug of those but of the callers (given fold_binary
> doesn't get to see that flag).
Exactly.
>
> > > see just
> > > switch (TREE_CODE_LENGTH (code))
> > > {
> > > case 1:
> > > op0 = TREE_OPERAND (t, 0);
> > > tem = fold_unary_loc (loc, code, type, op0);
> > > return tem ? tem : expr;
> > > case 2:
> > > op0 = TREE_OPERAND (t, 0);
> > > op1 = TREE_OPERAND (t, 1);
> > > tem = fold_binary_loc (loc, code, type, op0, op1);
> > > return tem ? tem : expr;
> > > case 3:
> > > op0 = TREE_OPERAND (t, 0);
> > > op1 = TREE_OPERAND (t, 1);
> > > op2 = TREE_OPERAND (t, 2);
> > > tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
> > > return tem ? tem : expr;
> > > without really trying to preserve anything.
>
> This would need to do the fixup in case of tcc_reference codes.
> Fortunately fold () calls are rare.
Well, both C and C++ FEs now call them pretty much on everything. So certainly
not rare.
