[Bug c++/108489] internal_error adding data fields in a promise_type

[janwilmans at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108489

--- Comment #2 from Jan Wilmans <janwilmans at gmail dot com> ---
tested: fails on all GCC versions after 10.1, including trunk.