https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117798
--- Comment #1 from kargls at comcast dot net ---
The following program comes from Fortran 2023, 16.9.92 GET_COMMAND.
PROGRAM hello
CHARACTER(:), ALLOCATABLE :: cmd
CALL GET_COMMAND(cmd)
PRINT *, 'Hello ', cmd
END PROGRAM
This hangs on x86_64-*-freebsd as it appears get_command is not
prepared to do an allocation of the needed memory. In looking
closer at Fortran 2023, one finds
4.3.3 Fortran 2018 compatibility
...
The following Fortran 2018 features might have a different interpretation
under this document.
ยท After an allocatable deferred length character variable is assigned
a value by an IOMSG= or ERRMSG= clause, is the unit in an internal
WRITE statement, or is an INTENT (OUT) argument in a reference to
an intrinsic subroutine, that variable might be of shorter or longer
length under this document than under Fortran 2018, since this
document specifies intrinsic assignment semantics for these assignments.
