On Tue, 12 Dec 2023, Patrick Palka wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK
> for trunk?
>
> -- >8 --
>
> When unifying constants we need to generally treat constants of
> different types but same value as different, in light of auto template
> parameters. This patch fixes this in a minimal way; it seems we could
> get away with just using template_args_equal here, as we do in the
or just cp_tree_equal for that matters because ...
> default case, but that's a simplification we could look into during next
> stage 1.
>
> PR c++/99186
> PR c++/104867
>
> gcc/cp/ChangeLog:
>
> * pt.cc (unify) <case INTEGER_CST>: Compare types as well.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/cpp1z/nontype-auto23.C: New test.
> * g++.dg/cpp1z/nontype-auto24.C: New test.
> ---
> gcc/cp/pt.cc | 2 ++
> gcc/testsuite/g++.dg/cpp1z/nontype-auto23.C | 23 +++++++++++++++++++++
> gcc/testsuite/g++.dg/cpp1z/nontype-auto24.C | 18 ++++++++++++++++
> 3 files changed, 43 insertions(+)
> create mode 100644 gcc/testsuite/g++.dg/cpp1z/nontype-auto23.C
> create mode 100644 gcc/testsuite/g++.dg/cpp1z/nontype-auto24.C
>
> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> index a8966e223f1..602dd02d29d 100644
> --- a/gcc/cp/pt.cc
> +++ b/gcc/cp/pt.cc
> @@ -24709,6 +24709,8 @@ unify (tree tparms, tree targs, tree parm, tree arg,
> int strict,
> /* Type INTEGER_CST can come from ordinary constant template args. */
> case INTEGER_CST:
> case REAL_CST:
> + if (!same_type_p (TREE_TYPE (parm), TREE_TYPE (arg)))
> + return unify_template_argument_mismatch (explain_p, parm, arg);
> while (CONVERT_EXPR_P (arg))
> arg = TREE_OPERAND (arg, 0);
... this while loop seems to be dead code.
>
> diff --git a/gcc/testsuite/g++.dg/cpp1z/nontype-auto23.C
> b/gcc/testsuite/g++.dg/cpp1z/nontype-auto23.C
> new file mode 100644
> index 00000000000..467559ffdda
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp1z/nontype-auto23.C
> @@ -0,0 +1,23 @@
> +// PR c++/99186
> +// { dg-do compile { target c++17 } }
> +
> +template<int N, typename T, typename... U>
> +struct tuple_impl : tuple_impl<N + 1, U...> { };
> +
> +template<int N, typename T>
> +struct tuple_impl<N, T> { };
> +
> +template<typename T, typename U>
> +struct tuple : tuple_impl<0, T, U> { };
> +
> +template<typename T, int N, typename... U>
> +void get(const tuple_impl<N, T, U...>&);
> +
> +template<auto>
> +struct S;
> +
> +int main() {
> + tuple<S<1>,S<1U>> x;
> + get<S<1U>>(x);
> + get<S<1>>(x);
> +}
> diff --git a/gcc/testsuite/g++.dg/cpp1z/nontype-auto24.C
> b/gcc/testsuite/g++.dg/cpp1z/nontype-auto24.C
> new file mode 100644
> index 00000000000..52e4c134ccd
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp1z/nontype-auto24.C
> @@ -0,0 +1,18 @@
> +// PR c++/104867
> +// { dg-do compile { target c++17 } }
> +
> +enum class Foo { A1 };
> +
> +enum class Bar { B1 };
> +
> +template<auto EnumVal> struct enum_;
> +
> +template<class...> struct list { };
> +
> +template<class V> void f(list<enum_<Bar::B1>, V>);
> +
> +struct enum_type_map : list<enum_<Foo::A1>, int>, list<enum_<Bar::B1>,
> double> { };
> +
> +int main() {
> + f(enum_type_map());
> +}
> --
> 2.43.0.76.g1a87c842ec
>
>
