OK.
On Tue, Jan 3, 2017 at 8:37 AM, Marek Polacek <pola...@redhat.com> wrote:
> The problem here is that we've gotten to potential_constant_expression_1 with
> a
> CLEANUP_STMT, but it doesn't know how to handle that so we ICE. I thought
> it'd
> be possible to look into CLEANUP_{BODY,EXPR} to determine whether the
> CLEANUP_STMT can be potentially const, but cxx_eval_constant_expression can't
> handle CLEANUP_STMTs so it couldn't evaluate it anyway. So it seems that it's
> safe to consider CLEANUP_STMTs non-constant.
>
> This happens when initializing __for_range, where finish_eh_cleanup creates
> a CLEANUP_STMT that would run ~A() in case of an exception.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2017-01-03 Marek Polacek <pola...@redhat.com>
>
> PR c++/77545
> PR c++/77284
> * constexpr.c (potential_constant_expression_1): Handle CLEANUP_STMT.
>
> * g++.dg/cpp0x/range-for32.C: New test.
> * g++.dg/cpp0x/range-for33.C: New test.
>
> diff --git gcc/cp/constexpr.c gcc/cp/constexpr.c
> index 1e83b0b..a3dec68 100644
> --- gcc/cp/constexpr.c
> +++ gcc/cp/constexpr.c
> @@ -5661,6 +5661,7 @@ potential_constant_expression_1 (tree t, bool
> want_rval, bool strict,
> /* We can see these in statement-expressions. */
> return true;
>
> + case CLEANUP_STMT:
> case EMPTY_CLASS_EXPR:
> return false;
>
> diff --git gcc/testsuite/g++.dg/cpp0x/range-for32.C
> gcc/testsuite/g++.dg/cpp0x/range-for32.C
> index e69de29..375a707 100644
> --- gcc/testsuite/g++.dg/cpp0x/range-for32.C
> +++ gcc/testsuite/g++.dg/cpp0x/range-for32.C
> @@ -0,0 +1,16 @@
> +// PR c++/77545
> +// { dg-do compile { target c++11 } }
> +// { dg-options "-Wno-pedantic" }
> +
> +template < typename T > struct A
> +{
> + A ();
> + ~A ();
> + T t;
> +};
> +
> +void f (A < int > a)
> +{
> + for (auto x : (A<int>[]) { a })
> + ;
> +}
> diff --git gcc/testsuite/g++.dg/cpp0x/range-for33.C
> gcc/testsuite/g++.dg/cpp0x/range-for33.C
> index e69de29..206f36e 100644
> --- gcc/testsuite/g++.dg/cpp0x/range-for33.C
> +++ gcc/testsuite/g++.dg/cpp0x/range-for33.C
> @@ -0,0 +1,14 @@
> +// PR c++/77284
> +// { dg-do compile { target c++11 } }
> +
> +#include <initializer_list>
> +
> +struct A
> +{
> + ~A () {}
> +};
> +
> +void foo (A & v)
> +{
> + for (A a : { v }) {};
> +}
>
> Marek
