On Tue, Jun 02, 2015 at 09:53:14AM +0100, Richard Sandiford wrote:
> unsigned int min_prec = (wi::min_precision (op0, SIGNED)
> + TREE_INT_CST_LOW (op1));
> bool overflowed = min_prec > TYPE_PRECISION (type0);
> if (overflowed && c_inhibit_evaluation_warnings == 0)
> warning_at (loc, OPT_Wshift_overflow,
> "result of %qE requires %u bits to represent, "
> "but %qT only has %u bits",
> build2_loc (loc, LSHIFT_EXPR, type0, op0, op1),
> min_prec, type0, TYPE_PRECISION (type0));
>
> which seems simpler than anything involving wider precision.
Clearly your version is much better, so I'll use it - thanks!
I'm testing a new version of the patch, will post it soon.
Marek
