[Bug c++/79687] [5/6/7 Regression] Wrong code with pointer-to-member

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79687

--- Comment #14 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Ah, I see cp_convert_to_pointer does

 212       /* A NULL pointer-to-data-member is represented by -1, not by
 213          zero.  */
 214       tree val = (TYPE_PTRDATAMEM_P (type)
 215                   ? build_int_cst_type (type, -1)
 216                   : build_int_cst (type, 0));