https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71952
--- Comment #3 from Dominique d'Humieres <dominiq at lps dot ens.fr> --- > Prior to 5.1, gfortran only supported single-image coarray execution. > Possibly it's a regression for behavior with -fcoarray=single, > but the more important case is -fcoarray=lib. -fcoarray=lib -lcaf_single is supported since at least 4.9.3. The "Sorry, coindexed access ..." errors have been implemented at revision r221549.