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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/101566] gcc miscompiles lambda used as tuple-like object
 applied to function for call
Date: Wed, 21 Jul 2021 19:56:55 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101566

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Dale Weiler from comment #5)
> This is curious, omitting `decltype(auto)` for get, as in just `auto` see=
ms
> to work around the issue as well.
>=20
> template<Size N, typename T>
> constexpr auto get(T tuple) { return *tuple(Get<N>{}); }
>=20
> I'm a bit out of my element here, in that I don't understand the semantic
> differences between the two and if that behavior is correct.

auto makes it return by value, decltype(auto) returns exactly the type of t=
he
return statement (so if it's a reference, so is the return type).=