[Bug c++/111230] New: show explicit functions in possible candidates

[Bug c++/111230] New: show explicit functions in possible candidates

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111230

            Bug ID: 111230
           Summary: show explicit functions in possible candidates
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mpolacek at gcc dot gnu.org
  Target Milestone: ---

struct T {
   T() { } // #1
   explicit T(const T&) { } // #2
};

void
g ()
{
   T t{};
   throw t;
}

shows

h.C: In function ‘void g()’:
h.C:10:10: error: no matching function for call to ‘T::T(T)’
   10 |    throw t;
      |          ^
h.C:2:4: note: candidate: ‘T::T()’
    2 |    T() { } // #1
      |    ^
h.C:2:4: note:   candidate expects 0 arguments, 1 provided
h.C:10:10: note:   in thrown expression
   10 |    throw t;
      |          ^

but it never mentions #2.

[Bug c++/111230] show explicit functions in possible candidates

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111230

Marek Polacek <mpolacek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2023-08-29
             Status|UNCONFIRMED                 |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |mpolacek at gcc dot gnu.org
           Keywords|                            |diagnostic

--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Jason: "in add_candidates when we see an explicit constructor we could add it
to bad_fns instead of ignoring it"

[Bug c++/111230] show explicit functions in possible candidates

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111230

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=36183

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Dup of PR 36183?

There Jason said:

We'd probably get that by changing add_candidates to mark an explicit candidate
as bad rather than non-viable, and then adding the explanation to
convert_like_real.