Ping.
On Thu, Oct 11, 2018 at 09:28:38PM -0400, Marek Polacek wrote:
> Recently it came up that no test in the testsuite triggers the RANGE_FOR_STMT
> case in potential_constant_expression_1. I came up with this valid test that
> tickles that codepath.
>
> I can't use ({ }) instead of a lambda because the constexpr machinery doesn't
> handle statement expressions; see default: in cxx_eval_constant_expression.
>
> Tested on x86_64-linux, ok for trunk?
>
> 2018-10-11 Marek Polacek <pola...@redhat.com>
>
> * g++.dg/cpp1z/constexpr-lambda22.C: New test,
>
> diff --git gcc/testsuite/g++.dg/cpp1z/constexpr-lambda22.C
> gcc/testsuite/g++.dg/cpp1z/constexpr-lambda22.C
> index e69de29bb2d..8bb473431a5 100644
> --- gcc/testsuite/g++.dg/cpp1z/constexpr-lambda22.C
> +++ gcc/testsuite/g++.dg/cpp1z/constexpr-lambda22.C
> @@ -0,0 +1,20 @@
> +// { dg-do compile }
> +// { dg-options -std=c++17 }
> +
> +#define SA(X) static_assert((X),#X)
> +
> +template<typename>
> +constexpr int
> +foo ()
> +{
> + constexpr int a[] = { 1, 2, 3, 4, 5 };
> + int i = 0;
> + auto j = [&] {
> + for (auto x : a)
> + i++;
> + return i;
> + }();
> + return j;
> +}
> +
> +SA (foo<int>() == 5);
Marek
