[Bug c++/106882] New: passing X as 'this' argument discards qualifiers

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106882

            Bug ID: 106882
           Summary: passing X as 'this' argument discards qualifiers
           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: ---

This should be accepted:

struct Mutt {
    operator int*() &&;
};

int* five(Mutt x) {
  return x;  // OK since C++20 because P1155
}

but is currently rejected with error: passing ‘Mutt’ as ‘this’ argument
discards qualifiers [-fpermissive]

Maybe we're not checking IMPLICIT_RVALUE_P where needed.

This blocks P2266.