[Bug c++/78001] [7 Regression] ncurses build error

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78001

--- Comment #5 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Well,

markus@x4 ~ % clang++ -c n.ii
n.ii:6:24: error: member function 'm_fn1' not viable: 'this' argument has type
'const B', but function is not marked const
  void m_fn2() const { m_fn1(); }
                       ^~~~~
n.ii:3:8: note: 'm_fn1' declared here
  void m_fn1();
       ^
1 error generated.

is clear immediately.