[Bug fortran/47040] Make error message for empty array constructor more helpful/correct

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47040

--- Comment #6 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
Patch submitted at https://gcc.gnu.org/ml/fortran/2016-04/msg00024.html.