OK, thanks.
Jason
On Fri, Feb 22, 2019 at 6:11 AM Marek Polacek <pola...@redhat.com> wrote:
>
> On Thu, Feb 21, 2019 at 03:47:44PM -1000, Jason Merrill wrote:
> > On 2/21/19 1:35 PM, Marek Polacek wrote:
> > > We were ICEing because we called build_converted_constant_expr on an
> > > expression
> > > that wasn't value-dependent, but it still contained template codes, and
> > > that
> > > didn't work too well because check_narrowing calls maybe_constant_value.
> >
> > Hmm, I'm concerned about convert_like_real from
> > build_converted_constant_expr adding more template codes; you probably want
> > a processing_template_decl_sentinel after the
> > instantiate_non_dependent_expr.
>
> OK, that's a good trick.
>
> > Also, value_dependent_expression_p should probably be
> > instantiation_dependent_expression_p.
>
> I think I used value_* because that's what build_noexcept_spec had. Also
> value_dependent_expression_p calls type_dependent_expression_p. But I've
> changed it anyway. Thanks,
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2019-02-22 Marek Polacek <pola...@redhat.com>
>
> PR c++/89420 - ICE with CAST_EXPR in explicit-specifier.
> * decl.c (build_explicit_specifier): Don't check
> processing_template_decl. Call instantiation_dependent_expression_p
> instead of value_dependent_expression_p. Call
> instantiate_non_dependent_expr_sfinae before
> build_converted_constant_expr instead of calling
> instantiate_non_dependent_expr after it. Add
> processing_template_decl_sentinel.
>
> * g++.dg/cpp2a/explicit14.C: New test.
>
> diff --git gcc/cp/decl.c gcc/cp/decl.c
> index 612afbacd27..c5b5bd3ce08 100644
> --- gcc/cp/decl.c
> +++ gcc/cp/decl.c
> @@ -16687,12 +16687,14 @@ require_deduced_type (tree decl, tsubst_flags_t
> complain)
> tree
> build_explicit_specifier (tree expr, tsubst_flags_t complain)
> {
> - if (processing_template_decl && value_dependent_expression_p (expr))
> + if (instantiation_dependent_expression_p (expr))
> /* Wait for instantiation, tsubst_function_decl will handle it. */
> return expr;
>
> + expr = instantiate_non_dependent_expr_sfinae (expr, complain);
> + /* Don't let convert_like_real create more template codes. */
> + processing_template_decl_sentinel s;
> expr = build_converted_constant_expr (boolean_type_node, expr, complain);
> - expr = instantiate_non_dependent_expr (expr);
> expr = cxx_constant_value (expr);
> return expr;
> }
> diff --git gcc/testsuite/g++.dg/cpp2a/explicit14.C
> gcc/testsuite/g++.dg/cpp2a/explicit14.C
> new file mode 100644
> index 00000000000..9c3acc32ac4
> --- /dev/null
> +++ gcc/testsuite/g++.dg/cpp2a/explicit14.C
> @@ -0,0 +1,11 @@
> +// PR c++/89420
> +// { dg-do compile { target c++2a } }
> +
> +template<typename>
> +struct S {
> + explicit(int(1)) S(int);
> + explicit(int{1}) S(int, int);
> +};
> +
> +S<int> s(1);
> +S<int> s2(1, 2);
