First time in my life I actually needed gdb. Guess why? Gnu g++

Forgot to add a virtual in some C++ class method declaration, g++ happily compiled it and it took f&!k¡n' gdb to find out what was actually SIGSEGV'ing it (gcc 7.3/x86_64, a 10+ years old C++ compiler weakness).
Hint: %rax gets assigned to the same caller entry point, looping over itself: generated code is OK, vtable is not.