[Bug c++/57248] string parameter to constexpr functions

["daniel.kruegler at googlemail dot com" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57248

--- Comment #3 from Daniel Krügler <daniel.kruegler at googlemail dot com> ---
The code looks valid to me. I think that Paolo just wanted to point out that
the library implementation does not cause this. I agree with him and can
confirm that the code is also rejected when emulating the library such as in
the following way:

template<bool, class>
struct enable_if{};

template<class T>
struct enable_if<true, T>{ typedef T type; };

template<class T1, class T2>
struct tuple
{
  T1 t1;
  T2 t2;
};

template<unsigned I, class T1, class T2>
constexpr
typename enable_if<I == 0, T1>::type
get(tuple<T1, T2> t) { return t.t1; }

template<unsigned I, class T1, class T2>
constexpr
typename enable_if<I == 1, T1>::type
get(tuple<T1, T2> t) { return t.t2; }

template<class T1, class T2>
constexpr tuple<T1, T2> make_tuple(T1 t1, T2 t2)
{
  return tuple<T1, T2>{t1, t2};
}

Same error here.
>From gcc-bugs-return-422995-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Thu May 23 21:34:47 2013
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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/57359] wrong code for union access at -O3 on x86_64-linux
Date: Thu, 23 May 2013 21:34:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?idW359

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
NP, and thanks a lot for the bugreports, they are very much appreciated.