[Patch/gfortran] PR18283

[Paul Thomas <paulthomas2 at wanadoo dot fr>]

This patch cures pr18283 that arises because character scalar pointer 
derived-type references cause an ICE in gfc_conv_string_parameter. 
This, in turn, is caused by an incorrect dereference in 
gfc_conv_component_ref.

Please excuse the diff relative to my own source.  The pending patch for 
pr18109 is from the same file.

Bubblestrapped and regtested on i686/RH9:  OK to commit?

Regards

Paul T

2005-05-29 Paul Thomas  <pault@gcc.gnu.org>

  PR fortran/18283
  * fortran/trans-expr.c (gfc_conv_component_ref): Remove the
  dereference of scalar character pointer structure components.

2005-05-29 Paul Thomas  <pault@gcc.gnu.org>

  * gfortran.dg/char_pointer_comp_assign.f90:
  Test character pointer structure component assignments.



! { dg-do run }
! This test the fix of PR18283, where assignments of scalar,
! character pointer components of derived types caused an ICE.
! It also checks that the array counterparts remain operational.
! Contributed by Paul Thomas  pault@gcc.gnu.org
!
program char_pointer_comp_assign
  implicit none
  type :: dt
     character (len=4), pointer :: scalar
     character (len=4), pointer :: array(:)
  end type dt
  type (dt) :: a 
  character (len=4), target :: scalar_t ="abcd"
  character (len=4), target :: array_t(2) = (/"abcd","efgh"/)

! Do assignments first
  allocate (a%scalar, a%array(2))
  a%scalar = scalar_t
  if (a%scalar /= "abcd") call abort ()
  a%array = array_t
  if (any(a%array /= (/"abcd","efgh"/))) call abort ()
  deallocate (a%scalar, a%array)

! Now do pointer assignments.
  a%scalar => scalar_t
  if (a%scalar /= "abcd") call abort ()
  a%array => array_t
  if (any(a%array /= (/"abcd","efgh"/))) call abort ()

end program char_pointer_comp_assign

*** /usr/windows/gcc-cvs/gcc/gcc/fortran/trans-expr.c	2005-05-30 14:25:55.000000000 +0200
--- /usr/windows/gfortran/character/trans-expr.c	2005-05-30 14:26:43.000000000 +0200
*************** gfc_conv_component_ref (gfc_se * se, gfc
*** 281,287 ****
        se->string_length = tmp;
      }
  
!   if (c->pointer && c->dimension == 0)
      se->expr = gfc_build_indirect_ref (se->expr);
  }
  
--- 281,287 ----
        se->string_length = tmp;
      }
  
!   if (c->pointer && c->dimension == 0 && c->ts.type != BT_CHARACTER)
      se->expr = gfc_build_indirect_ref (se->expr);
  }