Hello,
Yet another problem: I have a 3rd party code in which there is a "chain" of optional argument passing done without checking with 'present'.
It looks like tnis (example, I/O is done to use unpredictable data, to avoid compiler optimizations):
module m0016
contains
subroutine f(j)
implicit none
integer,intent(in),optional::j
integer i
write(*,*)'f(): enter i:'
read(*,*)i
call g(i,j)
return
end subroutine f
subroutine g(i,j)
implicit none
integer,intent(in)::i
integer,intent(in),optional::j
write(*,*)'g(): i=',i
if(present(j)) write(*,*)'g(): j=',j
return
end subroutine g
end module m0016
program test
use m0016
implicit none
integer::j
call f()
write(*,*)'main: enter j:'
read(*,*)j
call f(j)
stop
end program test
This code compiles and surprisingly works...
However use of j in f() in call to g() without 'present' looks strange...
Is such a careless use of optional arguments correct and allowed by Fortran standards?
