On Mon, Aug 13, 2018 at 11:24 PM, Marek Polacek <pola...@redhat.com> wrote:
> On Mon, Aug 13, 2018 at 10:14:21PM +1200, Jason Merrill wrote:
>> >> >> > --- gcc/cp/decl.c
>> >> >> > +++ gcc/cp/decl.c
>> >> >> > @@ -9581,7 +9581,7 @@ compute_array_index_type (tree name, tree
>> >> >> > size, tsubst_flags_t complain)
>> >> >> > {
>> >> >> > tree folded = cp_fully_fold (size);
>> >> >> > if (TREE_CODE (folded) == INTEGER_CST)
>> >> >> > - pedwarn (location_of (size), OPT_Wpedantic,
>> >> >> > + pedwarn (input_location, OPT_Wpedantic,
>> >> >>
>> >> >> It should work to use location_of (osize) here.
>> >> >
>> >> > I dropped this hunk altogether. Because location_of will use
>> >> > DECL_SOURCE_LOCATION for DECLs, the error message will point to the
>> >> > declaration
>> >> > itself, not the use. I don't really care either way.
>> >>
>> >> We want the message to point to the use, which location_of (osize)
>> >> will provide, since it should still have a location wrapper around a
>> >> DECL.
>> >
>> > location_of (osize) is actually the same as location_of (size) so that
>> > didn't
>> > change anything.
>>
>> Hunh, that's strange. Why isn't osize the unfolded expression? Where
>> is the location wrapper getting stripped?
>
> I actually see that it didn't have the location wrapper at the start.
> The array bound is parsed in cp_parser_direct_new_declarator, and we
> never called maybe_wrap_with_location to add the wrapper. I don't know
> where that's supposed to happen.
>
> This quick hack works
>
> --- a/gcc/cp/parser.c
> +++ b/gcc/cp/parser.c
> @@ -8681,6 +8681,7 @@ cp_parser_direct_new_declarator (cp_parser* parser)
> cp_parser_require (parser, CPP_CLOSE_SQUARE, RT_CLOSE_SQUARE);
>
> /* Add this bound to the declarator. */
> + expression = maybe_wrap_with_location (expression, token->location);
> declarator = make_array_declarator (declarator, expression);
>
> /* If the next token is not a `[', then there are no more
>
> but that feels too ad-hoc and beyond the scope of this fix.
>
>> > The code below uses input_location which is why I went with
>> > it in the first place. So, should I change this to input_location?
>>
>> I suppose so.
>
> Here's the version with input_location.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2018-08-13 Marek Polacek <pola...@redhat.com>
>
> PR c++/57891
> * call.c (struct conversion): Add check_narrowing_const_only.
> (build_converted_constant_expr): Set check_narrowing and
> check_narrowing_const_only. Give error if expr is error node.
> (convert_like_real): Pass it to check_narrowing.
> * cp-tree.h (check_narrowing): Add a default parameter.
> * decl.c (compute_array_index_type): Use input_location instead of
> location_of.
> * pt.c (convert_nontype_argument): Return NULL_TREE if tf_error.
> * typeck2.c (check_narrowing): Don't warn for instantiation-dependent
> expressions. Call maybe_constant_value instead of
> fold_non_dependent_expr. Don't mention { } in diagnostic. Only check
> narrowing for constants if CONST_ONLY.
This seems to have broken cpp1z/direct-enum-init1.C with -std=c++17
and above; please use make check-c++-all (or set
GXX_TESTSUITE_STDS=98,11,14,17,2a) to test C++ patches in all
conformance modes.
Jason
