On Thu, Dec 7, 2017 at 3:48 PM, Bernd Edlinger <bernd.edlin...@hotmail.de> wrote: > On 12/06/17 23:35, Jason Merrill wrote: >> On Fri, Dec 1, 2017 at 7:42 AM, Bernd Edlinger >> <bernd.edlin...@hotmail.de> wrote: >>> this version of the patch improves the heuristic check to take the >>> target hook into account, to handle cases correctly when both or only >>> one parameter is _not_ promoted to int. >> >> In looking at this, I discovered that the argument to >> promote_prototypes should be the function type, not the parameter >> type; the existing uses in the C++ front end were wrong. >> > > Bah, sorry. > > Yes, it looks like there are at least two more target hooks that change > the type promotion rules later-on: targetm.calls.promote_function_mode > and PROMOTE_MODE. > > In the ada FE we pass NULL_TREE to promote_prototypes which seems to > mean if the target wants type promotion in principle. So it returns > true if some function may promote, and false if no function promotes. > At least this is how the sh-target handles this parameter. > This is BTW the only target that uses the argument of this callback. > > So I would think for the purpose of this warning the following check > should be sufficient: > > if (INTEGRAL_TYPE_P (t1) > && INTEGRAL_TYPE_P (t2) > && TYPE_PRECISION (t1) == TYPE_PRECISION (t2) > && (TYPE_UNSIGNED (t1) == TYPE_UNSIGNED (t2) > || !targetm.calls.promote_prototypes (NULL_TREE) > || TYPE_PRECISION (t1) >= TYPE_PRECISION (integer_type_node))) > > > What do you think? > Is the patch OK with this change?
Yes. Jason
