[Bug fortran/34429] New: Fails: character(len=use_associated_const) function foo()

[Bug fortran/34429] New: Fails: character(len=use_associated_const) function foo()

[burnus at gcc dot gnu dot org]

I believe the following program is valid; it is compiled by g95, ifort, NAG
f95, but gfortran rejects it with:

  Error: Expression at (1) must be of INTEGER type

For the for KIND we had a similar problem, see
        PR fortran/31154
        PR fortran/31229
        PR fortran/33334
and     PR 34254

module m
  integer, parameter :: strlen = 5
end module m

character(strlen) function test()
  use m
  test = 'A'
end function test


-- 
           Summary: Fails: character(len=use_associated_const) function
                    foo()
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org
OtherBugsDependingO 32834
             nThis:


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[jv244 at cam dot ac dot uk]

-- 

jv244 at cam dot ac dot uk changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2007-12-11 11:09:22
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[pault at gcc dot gnu dot org]

------- Comment #1 from pault at gcc dot gnu dot org  2008-01-08 12:57 -------
This is fixed in a patch that I am working on that sorts out the whole business
of function characteristics in one go.

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |pault at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2007-12-11 11:09:22         |2008-01-08 12:57:15
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[pault at gcc dot gnu dot org]

------- Comment #2 from pault at gcc dot gnu dot org  2008-01-17 07:19 -------
Subject: Bug 34429

Author: pault
Date: Thu Jan 17 07:19:04 2008
New Revision: 131592

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=131592
Log:
2008-01-17  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/34429
        PR fortran/34431
        PR fortran/34471
        * decl.c : Remove gfc_function_kind_locus and
        gfc_function_type_locus. Add gfc_matching_function.
        (match_char_length): If matching a function and the length
        does not match, return MATCH_YES and try again later.
        (gfc_match_kind_spec): The same.
        (match_char_kind): The same.
        (gfc_match_type_spec): The same for numeric and derived types.
        (match_prefix): Rename as gfc_match_prefix.
        (gfc_match_function_decl): Except for function valued character
        lengths, defer applying kind, type and charlen info until the
        end of specification block.
        gfortran.h (gfc_statement): Add ST_GET_FCN_CHARACTERISTICS.
        parse.c (decode_specification_statement): New function.
        (decode_statement): Call it when a function has kind = -1. Set
        and reset gfc_matching function, as function statement is being
        matched.
        (match_deferred_characteristics): Simplify with a single call
        to gfc_match_prefix. Do appropriate error handling. In any
        case, make sure that kind = -1 is reset or corrected.
        (parse_spec): Call above on seeing ST_GET_FCN_CHARACTERISTICS.
        Throw an error if kind = -1 after last specification statement.
        parse.h : Prototype for gfc_match_prefix.

2008-01-17  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/34429
        * gfortran.dg/function_charlen_1.f90: New test.

        PR fortran/34431
        * gfortran.dg/function_types_1.f90: New test.
        * gfortran.dg/function_types_2.f90: New test.

        PR fortran/34471
        * gfortran.dg/function_kinds_4.f90: New test.
        * gfortran.dg/function_kinds_5.f90: New test.

        * gfortran.dg/defined_operators_1.f90: Errors now at function
        declarations.
        * gfortran.dg/private_type_4.f90: The same.
        * gfortran.dg/interface_15.f90: The same.
        * gfortran.dg/elemental_args_check_2.f90: The same.
        * gfortran.dg/auto_internal_assumed.f90: The same.


Added:
    trunk/gcc/testsuite/gfortran.dg/function_charlen_1.f90
    trunk/gcc/testsuite/gfortran.dg/function_kinds_4.f90
    trunk/gcc/testsuite/gfortran.dg/function_kinds_5.f90
    trunk/gcc/testsuite/gfortran.dg/function_types_1.f90
    trunk/gcc/testsuite/gfortran.dg/function_types_2.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/decl.c
    trunk/gcc/fortran/gfortran.h
    trunk/gcc/fortran/misc.c
    trunk/gcc/fortran/parse.c
    trunk/gcc/fortran/parse.h
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/auto_internal_assumed.f90
    trunk/gcc/testsuite/gfortran.dg/defined_operators_1.f90
    trunk/gcc/testsuite/gfortran.dg/elemental_args_check_2.f90
    trunk/gcc/testsuite/gfortran.dg/interface_15.f90
    trunk/gcc/testsuite/gfortran.dg/private_type_4.f90


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[pault at gcc dot gnu dot org]

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------- Comment #3 from pault at gcc dot gnu dot org  2008-01-17 10:12 -------
Fixed on trunk - see below for some remaining wrinkles, dug up by Tobias.  I
will keep this pR open until both are fixed.

Paul

wrinkle #1:  This one is easily fixed.

Index: gcc/fortran/decl.c
===================================================================
--- gcc/fortran/decl.c  (révision 131592)
+++ gcc/fortran/decl.c  (copie de travail)
@@ -2156,6 +2156,7 @@
      after the specification statements.  */
   if (gfc_matching_function
        && !(len && len->expr_type != EXPR_VARIABLE
+                && len->expr_type != EXPR_CONSTANT
                 && len->expr_type != EXPR_OP))
     {
       gfc_undo_symbols ();

module m
 integer, parameter :: l = 2
end module m

program test
 implicit none
 integer, parameter :: l = 5
 character(len=10) :: c
 c = f()
contains
 character(len=l) function f()
   use m
   print *, len(f)
! if (len(f) /= 2) call abort  ! gives 5 right now...
   f = "a"
 end function f
end program test
! { dg-final { cleanup-modules "m" } }

wrinkle #2:  This one is proving to be a bit recalcitrant.

module m
 character(2) :: l
end module m

 implicit none
!  character(4) :: l
 print *, f()
contains
 character(len=len(l)) function f()
   use m
   f = "4"
   if (len(f)==2) f= "2"
 end function f
end

where 'l' is found to be ambiguous; this must arise because the first match of
the length is leaving the symbol intact.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[burnus at gcc dot gnu dot org]

------- Comment #4 from burnus at gcc dot gnu dot org  2008-01-17 17:26 -------
For cross reference the commit patch was:
http://gcc.gnu.org/ml/fortran/2008-01/msg00197.html

Besides the previously mentioned problems, there is also the following:

 gfc_clear_ts (gfc_typespec *ts)
[...]
+  if (ts->kind != -1)
+    ts->kind = 0;

This causes a problem if *ts is uninitalized, which happens for instance in
intrinsic.c's add_conv:

  gfc_typespec from, to;
[...]
  gfc_clear_ts (&from);

Assume now that the uninitialized memory contains "-1" ...
(Found using valgrind which has dozens of warnings of the type "jump depends on
uninitialized memory".)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[dominiq at lps dot ens dot fr]

------- Comment #5 from dominiq at lps dot ens dot fr  2008-01-17 17:49 -------
>From comment #4:

+  if (ts->kind != -1)
+    ts->kind = 0;

I think this has been removed in the commit. However if you had it, it is not
removed by svn update
(I had to remove it manually).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[burnus at gcc dot gnu dot org]

------- Comment #6 from burnus at gcc dot gnu dot org  2008-01-17 18:07 -------
> +  if (ts->kind != -1)
> I think this has been removed in the commit.
Indeed. Thanks for the check, Dominique. Thus: Ignore that comment.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[pault at gcc dot gnu dot org]

------- Comment #7 from pault at gcc dot gnu dot org  2008-01-17 22:09 -------
(In reply to comment #6)
> > +  if (ts->kind != -1)
> > I think this has been removed in the commit.
> Indeed. Thanks for the check, Dominique. Thus: Ignore that comment.

Gents,

I tried to deal with the useful comment about branching on kind = -1.  I have
used the somewhat brutal device that you will now find in the tree.

Cheers

Paul 


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[pault at gcc dot gnu dot org]

------- Comment #8 from pault at gcc dot gnu dot org  2008-01-30 06:56 -------
Subject: Bug 34429

Author: pault
Date: Wed Jan 30 06:56:10 2008
New Revision: 131956

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=131956
Log:
2008-01-30  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/34975
        * symbol.c (gfc_delete_symtree, gfc_undo_symbols): Rename
        delete_symtree to gfc_delete_symtree.
        * gfortran.h : Add prototype for gfc_delete_symtree.
        * module.c (load_generic_interfaces): Transfer symbol to a
        unique symtree and delete old symtree, instead of renaming.
        (read_module): The rsym and the found symbol are the same, so
        the found symtree can be deleted.

        PR fortran/34429
        * decl.c (match_char_spec): Remove the constraint on deferred
        matching of functions and free the length expression.
        delete_symtree to gfc_delete_symtree.
        (gfc_match_type_spec): Whitespace.
        (gfc_match_function_decl): Defer characteristic association for
        all types except BT_UNKNOWN.
        * parse.c (decode_specification_statement): Only derived type
        function matching is delayed to the end of specification.

2008-01-30  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/34975
        * gfortran.dg/use_only_3.f90: New test.
        * gfortran.dg/use_only_3.inc: Modules for new test.

        PR fortran/34429
        * gfortran.dg/function_charlen_2.f90: New test.

Added:
    trunk/gcc/testsuite/gfortran.dg/function_charlen_2.f90
    trunk/gcc/testsuite/gfortran.dg/use_only_3.f90
    trunk/gcc/testsuite/gfortran.dg/use_only_3.inc
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/decl.c
    trunk/gcc/fortran/gfortran.h
    trunk/gcc/fortran/module.c
    trunk/gcc/fortran/parse.c
    trunk/gcc/fortran/symbol.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429

[Bug fortran/34429] Fails: character(len=use_associated_const) function foo()

[pault at gcc dot gnu dot org]

------- Comment #9 from pault at gcc dot gnu dot org  2008-01-30 07:03 -------
Fixed on trunk

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34429