[Bug fortran/31269] short-circuit in -fbounds-check

["mimo2 at free dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #5 from mimo2 at free dot fr  2007-03-20 08:56 -------
OK   but in the present situation, the execution could be different wether you
have -fbounds-check or not. Let's change the code by
program toto
 implicit none
 real    :: a(100)
 integer :: i, k
 a(:) = 1.
 do i=1,100
   if( i <= 10 .and. a(k(i)) > 0. ) write(*,*) i,a(i)
 enddo
end
which is perfectly legitimate, and with k(i) a function. I've understood that
when i>10, k will not be called when no bound-checking (there is presently
short-circuit) while it will be called if bound checking. As k(i) may have some
side effects, this could lead to different execution path.
  I still think that having a consistent behaviour between the two options is
the right thing to do. As short-circuit seems to be an extension of the
standard, the most sensible way would be to have an additionnal flag
-short-circuit which would allow the user to choose if he wants it or not, and
that this flag apply to all situations (i.e. bound-checking or not). 


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31269