[Bug libstdc++/114147] New: tuple allocator-extended constructor requires non-explicit default constructor

[Bug libstdc++/114147] New: tuple allocator-extended constructor requires non-explicit default constructor

[victor.dyachenko at protonmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

            Bug ID: 114147
           Summary: tuple allocator-extended constructor requires
                    non-explicit default constructor
           Product: gcc
           Version: 10.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: victor.dyachenko at protonmail dot com
  Target Milestone: ---

GCC 10.1 fails to compile this code (GCC 9.1 is OK):

#include <tuple>
#include <memory>

struct C {
    explicit C() = default;
};

int main()
{
    std::tuple<C, int> t(std::allocator_arg, std::allocator<char>{});
}

[Bug libstdc++/114147] tuple allocator-extended constructor requires non-explicit default constructor

[victor.dyachenko at protonmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #1 from __vic <victor.dyachenko at protonmail dot com> ---
Why _ImplicitDefaultCtor is required here?

      template<typename _Alloc,
               _ImplicitDefaultCtor<is_object<_Alloc>::value, _T1, _T2> = true>
        _GLIBCXX20_CONSTEXPR
        tuple(allocator_arg_t __tag, const _Alloc& __a)
        : _Inherited(__tag, __a) { }

Missing overload for explicit tuple(allocator_arg_t, ...)?

[Bug libstdc++/114147] tuple allocator-extended constructor requires non-explicit default constructor

[victor.dyachenko at protonmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #2 from __vic <victor.dyachenko at protonmail dot com> ---
Shouldn't this be added?

      template<typename _Alloc,
               _ExplicitDefaultCtor<is_object<_Alloc>::value, _T1, _T2> = true>
    explicit
        _GLIBCXX20_CONSTEXPR
        tuple(allocator_arg_t __tag, const _Alloc& __a)
        : _Inherited(__tag, __a) { }

[Bug libstdc++/114147] [10/11/12/13 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2024-02-28
      Known to work|                            |14.0
           Keywords|                            |rejects-valid
   Target Milestone|---                         |11.5
            Summary|tuple allocator-extended    |[10/11/12/13 Regression]
                   |constructor requires        |tuple allocator-extended
                   |non-explicit default        |constructor requires
                   |constructor                 |non-explicit default
                   |                            |constructor
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
N.B. GCC 10 is no longer supported.

This was fixed on trunk by r14-7225

[Bug libstdc++/114147] [11/12/13 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[victor.dyachenko at protonmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #4 from __vic <victor.dyachenko at protonmail dot com> ---
The latest gcc-14-20240225 snapshot doesn't include this fix. Is there any
chance to have this fixed in 14.1 release?

[Bug libstdc++/114147] [11/12/13/14 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|14.0                        |
            Summary|[11/12/13 Regression] tuple |[11/12/13/14 Regression]
                   |allocator-extended          |tuple allocator-extended
                   |constructor requires        |constructor requires
                   |non-explicit default        |non-explicit default
                   |constructor                 |constructor

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Ah it does include it, but it only affects C++20 and later. For older standards
the original code is still used.

[Bug libstdc++/114147] [11/12/13/14 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |redi at gcc dot gnu.org

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
For the record, it looks like I broke this in commit r10-908 by adding a
constraint to that constructor (which was good) but not adding another overload
with the explicit constraint (which was bad):

       // Allocator-extended constructors.

-      template<typename _Alloc>
+      template<typename _Alloc,
+              _ImplicitDefaultCtor<is_object<_Alloc>::value> = true>
        tuple(allocator_arg_t __tag, const _Alloc& __a)
        : _Inherited(__tag, __a) { }

[Bug libstdc++/114147] [11/12/13/14 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Patch posted: https://gcc.gnu.org/pipermail/gcc-patches/2024-March/646989.html

[Bug libstdc++/114147] [11/12/13/14 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jonathan Wakely <redi@gcc.gnu.org>:

https://gcc.gnu.org/g:0a545ac7000501844670add0b3560ebdbcb123c6

commit r14-9307-g0a545ac7000501844670add0b3560ebdbcb123c6
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Mar 1 11:16:58 2024 +0000

    libstdc++: Add missing std::tuple constructor [PR114147]

    I caused a regression with commit r10-908 by adding a constraint to the
    non-explicit allocator-extended default constructor, but seemingly
    forgot to add an explicit overload with the corresponding constraint.

    libstdc++-v3/ChangeLog:

            PR libstdc++/114147
            * include/std/tuple (tuple::tuple(allocator_arg_t, const Alloc&)):
            Add missing overload of allocator-extended default constructor.
            (tuple<T1,T2>::tuple(allocator_arg_t, const Alloc&)): Likewise.
            * testsuite/20_util/tuple/cons/114147.cc: New test.

[Bug libstdc++/114147] [11/12/13 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #9 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Jonathan Wakely
<redi@gcc.gnu.org>:

https://gcc.gnu.org/g:8a0a24b9a097452c576d5f409fe7efbafd6aef6b

commit r13-8457-g8a0a24b9a097452c576d5f409fe7efbafd6aef6b
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Mar 1 11:16:58 2024 +0000

    libstdc++: Add missing std::tuple constructor [PR114147]

    I caused a regression with commit r10-908 by adding a constraint to the
    non-explicit allocator-extended default constructor, but seemingly
    forgot to add an explicit overload with the corresponding constraint.

    libstdc++-v3/ChangeLog:

            PR libstdc++/114147
            * include/std/tuple (tuple::tuple(allocator_arg_t, const Alloc&)):
            Add missing overload of allocator-extended default constructor.
            (tuple<T1,T2>::tuple(allocator_arg_t, const Alloc&)): Likewise.
            * testsuite/20_util/tuple/cons/114147.cc: New test.

    (cherry picked from commit 0a545ac7000501844670add0b3560ebdbcb123c6)

[Bug libstdc++/114147] [11/12 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Jonathan Wakely
<redi@gcc.gnu.org>:

https://gcc.gnu.org/g:fbdeeb1604d52a8ece8631f70ecd64d925d31741

commit r12-10221-gfbdeeb1604d52a8ece8631f70ecd64d925d31741
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Mar 1 11:16:58 2024 +0000

    libstdc++: Add missing std::tuple constructor [PR114147]

    I caused a regression with commit r10-908 by adding a constraint to the
    non-explicit allocator-extended default constructor, but seemingly
    forgot to add an explicit overload with the corresponding constraint.

    libstdc++-v3/ChangeLog:

            PR libstdc++/114147
            * include/std/tuple (tuple::tuple(allocator_arg_t, const Alloc&)):
            Add missing overload of allocator-extended default constructor.
            (tuple<T1,T2>::tuple(allocator_arg_t, const Alloc&)): Likewise.
            * testsuite/20_util/tuple/cons/114147.cc: New test.

    (cherry picked from commit 0a545ac7000501844670add0b3560ebdbcb123c6)

[Bug libstdc++/114147] [11 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[11/12 Regression] tuple    |[11 Regression] tuple
                   |allocator-extended          |allocator-extended
                   |constructor requires        |constructor requires
                   |non-explicit default        |non-explicit default
                   |constructor                 |constructor

--- Comment #11 from Jonathan Wakely <redi at gcc dot gnu.org> ---
backported for 13.3 and 12.4

[Bug libstdc++/114147] [11 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

--- Comment #12 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jonathan Wakely
<redi@gcc.gnu.org>:

https://gcc.gnu.org/g:0ecb0967b4f7e68027492ac03e5dc03b5bcfdcf7

commit r11-11411-g0ecb0967b4f7e68027492ac03e5dc03b5bcfdcf7
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Mar 1 11:16:58 2024 +0000

    libstdc++: Add missing std::tuple constructor [PR114147]

    I caused a regression with commit r10-908 by adding a constraint to the
    non-explicit allocator-extended default constructor, but seemingly
    forgot to add an explicit overload with the corresponding constraint.

    libstdc++-v3/ChangeLog:

            PR libstdc++/114147
            * include/std/tuple (tuple::tuple(allocator_arg_t, const Alloc&)):
            Add missing overload of allocator-extended default constructor.
            (tuple<T1,T2>::tuple(allocator_arg_t, const Alloc&)): Likewise.
            * testsuite/20_util/tuple/cons/114147.cc: New test.

    (cherry picked from commit 0a545ac7000501844670add0b3560ebdbcb123c6)

[Bug libstdc++/114147] [11 Regression] tuple allocator-extended constructor requires non-explicit default constructor

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114147

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|ASSIGNED                    |RESOLVED

--- Comment #13 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Fixed for 11.5, 12.4, 13.3 and 14.1