[Bug c++/104410] New: Internal error using default-initialized constexpr bool in requires clause

[Bug c++/104410] New: Internal error using default-initialized constexpr bool in requires clause

[oliver.rosten at googlemail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

            Bug ID: 104410
           Summary: Internal error using default-initialized constexpr
                    bool in requires clause
           Product: gcc
           Version: 11.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: oliver.rosten at googlemail dot com
  Target Milestone: ---

#include <type_traits>

template<class T>
constexpr bool use_func_v{};

// Using this instead is fine!
//template<class T>
//constexpr bool use_func_v{false};

struct func_obj
{
    template<class T>
        requires use_func_v<T>
    void operator()(T, T) const
    {}
};

constexpr bool bar{std::is_invocable_v<func_obj, char, char>};

----> internal error, see

https://godbolt.org/z/qsbPYq67a

[Bug c++/104410] [11/12 Regression] Internal error using default-initialized constexpr bool in requires clause

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |11.1.0, 11.2.0
           Keywords|                            |ice-on-valid-code
   Target Milestone|---                         |11.3
            Summary|Internal error using        |[11/12 Regression] Internal
                   |default-initialized         |error using
                   |constexpr bool in requires  |default-initialized
                   |clause                      |constexpr bool in requires
                   |                            |clause
      Known to work|                            |10.3.0

[Bug c++/104410] [11/12 Regression] Internal error using default-initialized constexpr bool in requires clause

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2022-02-06

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Self contained example (without the include):
template<class T>
constexpr bool use_func_v{};
struct func_obj
{
    template<class T>
        requires use_func_v<T>
    void operator()(T, T) const
    {}
};

template <typename t, typename ...args>
concept tt = requires {t{}(args{}...);};

constexpr bool bar{tt<func_obj, char, char>};

[Bug c++/104410] [11/12 Regression] Internal error using default-initialized constexpr bool in requires clause

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
here is slightly more reduced:
constexpr bool use_func_v{};
struct func_obj
{
    template<class T> requires use_func_v
    void operator()(T);
};
template <typename t, typename ...args>
concept tt = requires {t{}(args{}...);};
constexpr bool bar{tt<func_obj, char>};

[Bug c++/104410] [11/12 Regression] Internal error using default-initialized constexpr bool in requires clause

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

[Bug c++/104410] [11/12 Regression] Internal error using default-initialized constexpr bool in requires clause

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|needs-bisection             |
                 CC|                            |ppalka at gcc dot gnu.org
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |ppalka at gcc dot gnu.org

--- Comment #3 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Started with r11-6321.  I suppose the underlying problem is that the assert in
satisfaction_value should is too strict, it should be relaxed to accept
cv-qualified bool.

[Bug c++/104410] [11/12 Regression] Internal error using default-initialized constexpr bool in requires clause

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Patrick Palka <ppalka@gcc.gnu.org>:

https://gcc.gnu.org/g:7ff201d85fad11ba6365a5612124b75b385a97bd

commit r12-7103-g7ff201d85fad11ba6365a5612124b75b385a97bd
Author: Patrick Palka <ppalka@redhat.com>
Date:   Tue Feb 8 09:11:29 2022 -0500

    c++: satisfaction value of type const bool [PR104410]

    Here constant evaluation of the atomic constraint use_func_v<T>
    sensibly yields an INTEGER_CST of type const bool, but the assert in
    satisfaction_value expects unqualified bool.  So let's just relax the
    assert to accept cv-qualified bool.

            PR c++/104410

    gcc/cp/ChangeLog:

            * constraint.cc (satisfaction_value): Relax assert to accept
            cv-qualified bool.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/concepts-pr104410.C: New test.

[Bug c++/104410] [11 Regression] Internal error using default-initialized constexpr bool in requires clause

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[11/12 Regression] Internal |[11 Regression] Internal
                   |error using                 |error using
                   |default-initialized         |default-initialized
                   |constexpr bool in requires  |constexpr bool in requires
                   |clause                      |clause

--- Comment #5 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Fixed for GCC 12 so far.

[Bug c++/104410] [11 Regression] Internal error using default-initialized constexpr bool in requires clause

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Patrick Palka
<ppalka@gcc.gnu.org>:

https://gcc.gnu.org/g:411db3b4cf8655ecb5b7d666318546c73f2d156b

commit r11-9544-g411db3b4cf8655ecb5b7d666318546c73f2d156b
Author: Patrick Palka <ppalka@redhat.com>
Date:   Tue Feb 8 09:11:29 2022 -0500

    c++: satisfaction value of type const bool [PR104410]

    Here constant evaluation of the atomic constraint use_func_v<T>
    sensibly yields an INTEGER_CST of type const bool, but the assert in
    satisfaction_value expects unqualified bool.  So let's just relax the
    assert to accept cv-qualified bool.

            PR c++/104410

    gcc/cp/ChangeLog:

            * constraint.cc (satisfaction_value): Relax assert to accept
            cv-qualified bool.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/concepts-pr104410.C: New test.

    (cherry picked from commit 7ff201d85fad11ba6365a5612124b75b385a97bd)

[Bug c++/104410] [11 Regression] Internal error using default-initialized constexpr bool in requires clause

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104410

Patrick Palka <ppalka at gcc dot gnu.org> changed:

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

--- Comment #7 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Fixed for GCC 11.3/12.