[Bug fortran/38507] Bogus Warning: Deleted feature: GOTO jumps to END of construct

[kargl at gcc dot gnu dot org]

------- Comment #4 from kargl at gcc dot gnu dot org  2008-12-12 22:58 -------
(In reply to comment #3)
> What is about the obsolescent DO related part? Do we need to do
> something there
> (from F95, B.2):
> 
> "Shared DO termination and termination on a statement other than END DO or
> CONTINUE — use an END DO or a CONTINUE statement for each DO statement."
> 

AFAICT, gfortran in resolve.c(resolve_branch) makes no distinction between
a block do construct and a nonblock do construct.  The issue Harald raised
is jumping from some location inside the do-loop to a labeled end-do.
Before CYCLE, this was a common way to skip to the end of the loop.  I'm
surprise that this hasn't come up before.

In playing around with various Do---ENDDO and IF---ENDIF constructs,
I've found that gfortran considerd ENDDO to be a part of its do block
and ENDIF is not part of its if block.  I haven't read the standard 
to determine if these are the correct semantics, but sure looks
weird to me.

troutmask:sgk[207] cat e.f90
program a
  i = 1

  goto 1
  if (i == 1) then
     i = i + 1
1 end if

  goto 2
  do i = 1, 3
     j = i 
2 end do

end program a
troutmask:sgk[208] gfortran43 -c e.f90
e.f90:12.1:

2 end do
1
e.f90:9.8:

  goto 2
       2
Warning: Label at (1) is not in the same block as the GOTO statement at (2)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38507