https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109824
--- Comment #1 from Stas Sergeev <stsp at users dot sourceforge.net> --- Sorry, copied the output from wrong place. The real error msg looks like this: $ g++ -Wall -c a.cpp a.cpp: In member function ‘less_aligned_a& t1::get_ref()’: a.cpp:17:16: error: cannot bind packed field ‘((t1*)this)->t1::i’ to ‘less_aligned_a&’ {aka ‘a&’} 17 | return i;