Re: [Patch, fortran] PR58618 - Wrong code with character substring and ASSOCIATE

[Paul Richard Thomas <paul.richard.thomas@gmail.com>]

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I do not think that there will be a PR for the ICE. This is a
regression introduced by my patch for PR70149 (September 30th). A
patch is attached. I will commit it as 'obvious' as soon as it has
finished regtesting. I will also commit the patch for PR58618 shortly
afterwards. Thanks for the review.

Paul

On Wed, 17 Oct 2018 at 22:17, Tobias Burnus <burnus@net-b.de> wrote:
>
> Hi Paul,
>
> Paul Richard Thomas wrote:
> > This problem concerned associate targets being substrings. It turns
> > out that they are returned as pointer types (with a different cast for
> > unity based substrings ***sigh***) and so can be assigned directly to
> > the associate name. The patch quite simply removed the condition that
> > such targets be allocatable, pointer or dummy.
> > I noticed in the course of working up the testcase that
> >      character (:), pointer :: ptr => NULL()
> >      character (6), target :: tgt = 'lmnopq'
> >      ptr => tgt
> >      print *, len (ptr), ptr
> > end
> > ICEs on the NULL initialization of the pointer but works fine if this
> > is removed. Has this already been posted as a PR?
>
>
> I leave it to Dominique to search for a PR; otherwise, I believe the
> attach patch fixes the issue. – It just needs someone to package it with
> a test case, regtest and commit it.
>
>
> > Bootstrapped and regtested on FC28/x86_64 - OK for trunk?
>
> OK – thanks for the fix.
>
> Tobias
>
> > 2018-10-17  Paul Thomas  <pault@gcc.gnu.org>
> >
> >      PR fortran/58618
> >      * trans-stmt.c (trans_associate_var): All strings that return
> >      as pointer types can be assigned directly to the associate
> >      name so remove 'attr' and the condition that uses it.
> >
> > 2018-10-17  Paul Thomas  <pault@gcc.gnu.org>
> >
> >      PR fortran/58618
> >      * gfortran.dg/associate_45.f90 : New test.



-- 
"If you can't explain it simply, you don't understand it well enough"
- Albert Einstein

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Index: gcc/fortran/trans-decl.c
===================================================================
*** gcc/fortran/trans-decl.c	(revision 265231)
--- gcc/fortran/trans-decl.c	(working copy)
*************** gfc_get_symbol_decl (gfc_symbol * sym)
*** 1762,1768 ****
        gfc_finish_var_decl (length, sym);
        if (!sym->attr.associate_var
  	  && TREE_CODE (length) == VAR_DECL
! 	  && sym->value && sym->value->ts.u.cl->length)
  	{
  	  gfc_expr *len = sym->value->ts.u.cl->length;
  	  DECL_INITIAL (length) = gfc_conv_initializer (len, &len->ts,
--- 1762,1769 ----
        gfc_finish_var_decl (length, sym);
        if (!sym->attr.associate_var
  	  && TREE_CODE (length) == VAR_DECL
! 	  && sym->value && sym->value->expr_type != EXPR_NULL
! 	  && sym->value->ts.u.cl->length)
  	{
  	  gfc_expr *len = sym->value->ts.u.cl->length;
  	  DECL_INITIAL (length) = gfc_conv_initializer (len, &len->ts,
*************** gfc_get_symbol_decl (gfc_symbol * sym)
*** 1772,1778 ****
  						DECL_INITIAL (length));
  	}
        else
! 	gcc_assert (!sym->value);
      }
  
    gfc_finish_var_decl (decl, sym);
--- 1773,1779 ----
  						DECL_INITIAL (length));
  	}
        else
! 	gcc_assert (!sym->value || sym->value->expr_type == EXPR_NULL);
      }
  
    gfc_finish_var_decl (decl, sym);
Index: gcc/testsuite/gfortran.dg/deferred_character_30.f90
===================================================================
*** gcc/testsuite/gfortran.dg/deferred_character_30.f90	(nonexistent)
--- gcc/testsuite/gfortran.dg/deferred_character_30.f90	(working copy)
***************
*** 0 ****
--- 1,9 ----
+ ! { dg-do compile }
+ !
+ ! Fix a regression introduced by the patch for PR70149.
+ !
+     character (:), pointer :: ptr => NULL() ! The NULL () caused an ICE.
+     character (6), target :: tgt = 'lmnopq'
+     ptr => tgt
+     print *, len (ptr), ptr
+ end