[Bug libstdc++/110853] [13/14/15/16 Regression] Bad interaction between deduction guide with decay and constraints (CTAD, std::pair and function lvalue)

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110853

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2025-09-02
      Known to fail|                            |11.5.0
           Assignee|unassigned at gcc dot gnu.org      |redi at gcc dot gnu.org
            Summary|[c++-concepts] Bad          |[13/14/15/16 Regression]
                   |interaction between         |Bad interaction between
                   |deduction guide with decay  |deduction guide with decay
                   |and constraints (CTAD,      |and constraints (CTAD,
                   |std::pair and function      |std::pair and function
                   |lvalue)                     |lvalue)
   Target Milestone|---                         |13.5

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This is a regression caused by the new concepts-based constructor constraints
in gcc 12.