[Bug fortran/67779] Strange ordering with strings in extended object

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67779

--- Comment #22 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
> Created attachment 37201 [details]
> the right patch this time

Works as expected without regression!