Re: [Patch, Fortran] PR fortran/39626: Implement Fortran 2008's BLOCK construct

[Tobias Burnus <burnus at net-b dot de>]

Am 28.09.2009 16:47, schrieb Daniel Kraft:
> here's my revised patch to implement the BLOCK construct that will
> appear in the upcoming Fortran 2008 standard.  I personally believe that
> this is some really nice feature that missed for a long time, and also
> heard others say they'd like to have something like this in Fortran.
I also missed it a couple of times when I wanted to temporary add some
debugging WRITEs. One usually needs additionally variables which was
inconvenient  for lengthy subroutines.

> The patch is against today's trunk and passed both a full bootstrap and
> regression test on GNU/Linux-x86-32.  Ok for trunk?

The patch looks good to me. It sometimes makes the diagnostics less
useful, e.g. for

recursive function func(i)
  integer :: i, func
  func = 1
entry func2(i)
  block
    func2 = func(1)
  end block
end function func

But the same "Unclassifiable statement" one gets if one not only removes
"(end )block" but also "recursive".

> PPS: In block_2.f08, is there an easy way to check that the local
> allocatable array gets free'ed on exit of the block?  (Marked by an XXX
> comment)  If not, I think it won't hurt much to just get rid of the
> comment and not check this, but if there is, it would be cool to add
> this check.

You could try -fdump-tree-original together with some pattern in
! { dg-final { scan-tree-dump-times "<pattern>" <count> "original" } }

Tobias