https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96486
kargl at gcc dot gnu.org changed: What |Removed |Added ---------------------------------------------------------------------------- Priority|P3 |P4 Status|WAITING |NEW --- Comment #5 from kargl at gcc dot gnu.org --- (In reply to Susi Lehtola from comment #4) > $ export HOSTNAME=foo > $ ./a.out > $ > > $ export HOSTNAME= > $ ./a.out > Fortran runtime error: Zero-length string passed as value to > get_environment_variable. > > Error termination. Backtrace: > #0 0x7f25c93aadf1 in ??? > #1 0x7f25c93ab939 in ??? > #2 0x7f25c93abe60 in ??? > #3 0x7f25c960ce53 in ??? > #4 0x401267 in ??? > #5 0x4012c4 in ??? > #6 0x7f25c903a041 in __libc_start_main > at ../csu/libc-start.c:308 > #7 0x4010ad in ??? > #8 0xffffffffffffffff in ??? > $ Thanks. What gfortran version and operating system? I get % gfcx -o z b.f90 && ./z STOP System variable unassigned % gfcx -o z -g b.f90 && ./z STOP System variable unassigned % gfcx -o z -g -O b.f90 && ./z STOP System variable unassigned with your code where gfcx is gfortran 10.0.0 (Jan 2020 vintage) and I'm using i585-*-freebsd.