OK.
On Tue, Apr 11, 2017 at 1:13 PM, Jakub Jelinek <ja...@redhat.com> wrote:
> On Tue, Apr 11, 2017 at 03:41:39PM +0200, Jakub Jelinek wrote:
>> So like this? Or just type_dependent_expression_p check rather than
>> both?
>
> To answer myself, testing there both type_dependent_expression_p
> and value_dependent_expression_p for value_expr breaks
> the lambda-generic-const2.C testcase. So I'll test this instead:
>
> 2017-04-11 Jakub Jelinek <ja...@redhat.com>
>
> PR c++/80370
> * decl.c (cp_finish_decomp): If processing_template_decl on
> non-dependent decl, only set TREE_TYPE on the v[i] decls, but don't
> change their DECL_VALUE_EXPR nor cp_finish_decl them. Instead make
> sure DECL_VALUE_EXPR is the canonical NULL type ARRAY_REF for tsubst
> processing.
> * pt.c (value_dependent_expression_p) <case VAR_DECL>: For variables
> with DECL_VALUE_EXPR, return true if DECL_VALUE_EXPR is type
> dependent.
>
> * g++.dg/cpp1z/decomp28.C: New test.
>
> --- gcc/cp/decl.c.jj 2017-04-10 22:26:56.441388051 +0200
> +++ gcc/cp/decl.c 2017-04-11 15:21:24.473163169 +0200
> @@ -7473,6 +7473,8 @@ cp_finish_decomp (tree decl, tree first,
> {
> TREE_TYPE (v[i]) = eltype;
> layout_decl (v[i], 0);
> + if (processing_template_decl)
> + continue;
> tree t = unshare_expr (dexp);
> t = build4_loc (DECL_SOURCE_LOCATION (v[i]), ARRAY_REF,
> eltype, t, size_int (i), NULL_TREE,
> @@ -7492,6 +7494,8 @@ cp_finish_decomp (tree decl, tree first,
> {
> TREE_TYPE (v[i]) = eltype;
> layout_decl (v[i], 0);
> + if (processing_template_decl)
> + continue;
> tree t = unshare_expr (dexp);
> t = build1_loc (DECL_SOURCE_LOCATION (v[i]),
> i ? IMAGPART_EXPR : REALPART_EXPR, eltype,
> @@ -7510,6 +7514,8 @@ cp_finish_decomp (tree decl, tree first,
> {
> TREE_TYPE (v[i]) = eltype;
> layout_decl (v[i], 0);
> + if (processing_template_decl)
> + continue;
> tree t = unshare_expr (dexp);
> convert_vector_to_array_for_subscript (DECL_SOURCE_LOCATION (v[i]),
> &t, size_int (i));
> @@ -7559,8 +7565,9 @@ cp_finish_decomp (tree decl, tree first,
> SET_DECL_VALUE_EXPR (v[i], NULL_TREE);
> DECL_HAS_VALUE_EXPR_P (v[i]) = 0;
> }
> - cp_finish_decl (v[i], init, /*constexpr*/false,
> - /*asm*/NULL_TREE, LOOKUP_NORMAL);
> + if (!processing_template_decl)
> + cp_finish_decl (v[i], init, /*constexpr*/false,
> + /*asm*/NULL_TREE, LOOKUP_NORMAL);
> }
> }
> else if (TREE_CODE (type) == UNION_TYPE)
> @@ -7615,12 +7622,26 @@ cp_finish_decomp (tree decl, tree first,
> tt = TREE_OPERAND (tt, 0);
> TREE_TYPE (v[i]) = TREE_TYPE (tt);
> layout_decl (v[i], 0);
> - SET_DECL_VALUE_EXPR (v[i], tt);
> - DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
> + if (!processing_template_decl)
> + {
> + SET_DECL_VALUE_EXPR (v[i], tt);
> + DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
> + }
> i++;
> }
> }
> - if (DECL_NAMESPACE_SCOPE_P (decl))
> + if (processing_template_decl)
> + {
> + for (unsigned int i = 0; i < count; i++)
> + if (!DECL_HAS_VALUE_EXPR_P (v[i]))
> + {
> + tree a = build_nt (ARRAY_REF, decl, size_int (i),
> + NULL_TREE, NULL_TREE);
> + SET_DECL_VALUE_EXPR (v[i], a);
> + DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
> + }
> + }
> + else if (DECL_NAMESPACE_SCOPE_P (decl))
> SET_DECL_ASSEMBLER_NAME (decl, mangle_decomp (decl, v));
> }
>
> --- gcc/cp/pt.c.jj 2017-04-11 19:06:52.871624849 +0200
> +++ gcc/cp/pt.c 2017-04-11 19:10:39.795803274 +0200
> @@ -23576,6 +23576,12 @@ value_dependent_expression_p (tree expre
> || type_dependent_expression_p (DECL_INITIAL (expression))
> || value_dependent_expression_p (DECL_INITIAL (expression))))
> return true;
> + if (DECL_HAS_VALUE_EXPR_P (expression))
> + {
> + tree value_expr = DECL_VALUE_EXPR (expression);
> + if (type_dependent_expression_p (value_expr))
> + return true;
> + }
> return false;
>
> case DYNAMIC_CAST_EXPR:
> --- gcc/testsuite/g++.dg/cpp1z/decomp28.C.jj 2017-04-11 15:21:24.473163169
> +0200
> +++ gcc/testsuite/g++.dg/cpp1z/decomp28.C 2017-04-11 15:21:24.473163169
> +0200
> @@ -0,0 +1,39 @@
> +// PR c++/80370
> +// { dg-do compile { target c++14 } }
> +// { dg-options "" }
> +
> +namespace std {
> + template <typename> struct tuple_size;
> + template <long, typename> struct tuple_element;
> + template <typename...> struct tuple {};
> + template <typename... T> struct tuple_size<tuple<T...>> { static constexpr
> int value = 1; };
> + template <typename T, typename... U> struct tuple_element<0, tuple<T,
> U...>> { typedef T type; };
> + template <int, typename... T> int& get (tuple<T...>);
> +}
> +
> +template <int N>
> +void
> +foo (std::tuple<int> b)
> +{
> + auto [c] = b; // { dg-warning "decomposition declaration
> only available with" "" { target c++14_down } }
> +}
> +
> +template <typename T>
> +void
> +bar (std::tuple<T> b)
> +{
> + auto [c] = b; // { dg-warning "decomposition declaration
> only available with" "" { target c++14_down } }
> +}
> +
> +void
> +baz (std::tuple<int> b)
> +{
> + foo <5> (b);
> + bar (b);
> +}
> +
> +int
> +main ()
> +{
> + [](auto) { [](std::tuple<int> b) { auto[c] = b; }; } (0); // { dg-warning
> "decomposition declaration only available with" "" { target c++14_down } }
> +}
>
>
> Jakub
