[Bug fortran/29912] New: Gfortran: string array functions behaving incorrectly...

[Bug fortran/29912] New: Gfortran: string array functions behaving incorrectly...

[pmason at ricardo dot com]

When running following program (fortran90) which calls a 
string array function the result seems incorrect:

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
 program testat
 character(len=4)   :: ctemp(2)
 character(len=512) :: temper(2)
 !
 !------------------------
 !'This is OK.'
 !------------------------
 temper(1) = 'doncaster'
 temper(2) = 'uxbridge'
 ctemp     = temper
 print*,'ctemp(1) = ',ctemp(1)
 print*,'ctemp(2) = ',ctemp(2)
 !
 !------------------------
 !'This goes a bit wrong.'
 !------------------------
 print*,' '
 ctemp = jetter(1,2)
 print*,'ctemp(1) = ',ctemp(1)
 print*,'ctemp(2) = ',ctemp(2)

 contains
   function jetter(id1,id2)
   character(len=512) :: jetter(id1:id2)
   jetter(id1) = 'doncaster'
   jetter(id2) = 'uxbridge'
   end function jetter
 end program testat
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

This was run on a suse9(x86_64) box. Compiled using
gfortran (4.3.0 20061120 (experimental)). I think
that the "ctemp = jetter" statement should truncate
the strings in the same way as the "ctemp = temper"
statement (shouldn't it?).


-- 
           Summary: Gfortran: string array functions behaving incorrectly...
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pmason at ricardo dot com
 GCC build triplet: gcc version 4.3.0 20061120 (experimental)
  GCC host triplet: suse9
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2006-11-20 15:45 -------
Confirmed, gfortran forgets to use a temporary for the function call.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
  GCC build triplet|gcc version 4.3.0 20061120  |
                   |(experimental)              |
   GCC host triplet|suse9                       |
 GCC target triplet|x86_64-unknown-linux-gnu    |
           Keywords|                            |wrong-code
   Last reconfirmed|0000-00-00 00:00:00         |2006-11-20 15:45:09
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[jvdelisle at gcc dot gnu dot org]

------- Comment #2 from jvdelisle at gcc dot gnu dot org  2006-11-21 00:36 -------
Wow, on x86-64 this gives a beautiful seg fault.

(gdb) bt
#0  0x0000000000400afc in MAIN__ () at jetter.f90:20
Cannot access memory at address 0x2020202020202028


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[pault at gcc dot gnu dot org]

------- Comment #3 from pault at gcc dot gnu dot org  2006-11-21 12:10 -------
This is invalid code, isn't it?; I cannot quote you chapter and verse right now
but the total extent of a "receiving" character array has to be bigger than the
"sender", exactly to prevent problems of this kind.

Paul


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[pmason at ricardo dot com]

------- Comment #4 from pmason at ricardo dot com  2006-11-21 12:38 -------
I'm not 100% certain, but I think it is valid code.
I think the "Fortran Standard" states that when assigning
string(s) of different lengths that if the lhs string(s) are shorter
than the rhs then the strings are truncated accordingly.

The statements in the example code:

ctemp = temper
ctemp = jetter(1,2)

are actually equivalent (from a fortran90 point of view) aren't they?.

NOTE1: changing the ctemp declaration to be bigger (e.g. len=514) prevents
memory/corruption but assignment still goes wrong.

NOTE2: All other f90 compilers I have tried seems to handle this "correctly."


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[pault at gcc dot gnu dot org]

------- Comment #5 from pault at gcc dot gnu dot org  2006-11-21 12:59 -------
(In reply to comment #4)
> I'm not 100% certain, but I think it is valid code.
> I think the "Fortran Standard" states that when assigning
> string(s) of different lengths that if the lhs string(s) are shorter
> than the rhs then the strings are truncated accordingly.
> 
> The statements in the example code:
> 
> ctemp = temper
> ctemp = jetter(1,2)
> 
> are actually equivalent (from a fortran90 point of view) aren't they?.
> 
> NOTE1: changing the ctemp declaration to be bigger (e.g. len=514) prevents
> memory/corruption but assignment still goes wrong.
> 
> NOTE2: All other f90 compilers I have tried seems to handle this "correctly."
> 
I will check the standard - it might well be that you are right; what I said
applies to actual arguments, doen't it?

Paul


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[pmason at ricardo dot com]

------- Comment #6 from pmason at ricardo dot com  2006-11-21 13:27 -------
(In reply to comment #5)
> (In reply to comment #4)
> > I'm not 100% certain, but I think it is valid code.
> > I think the "Fortran Standard" states that when assigning
> > string(s) of different lengths that if the lhs string(s) are shorter
> > than the rhs then the strings are truncated accordingly.
> > 
> > The statements in the example code:
> > 
> > ctemp = temper
> > ctemp = jetter(1,2)
> > 
> > are actually equivalent (from a fortran90 point of view) aren't they?.
> > 
> > NOTE1: changing the ctemp declaration to be bigger (e.g. len=514) prevents
> > memory/corruption but assignment still goes wrong.
> > 
> > NOTE2: All other f90 compilers I have tried seems to handle this "correctly."
> > 
> I will check the standard - it might well be that you are right; what I said
> applies to actual arguments, doen't it?
> 
> Paul
> 

For the case of acutal (non-return) arguments with different len='s you would
expect it go wrong. I think the main problem here was alluded to in comment #1:
i.e. the fact a TEMP array isn't used for return arg. If it was, then the
statememt "ctemp = jetter(1,2)" would reduce "ctemp = temper" where string
trunctation/padding rules wolud apply.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[pault at gcc dot gnu dot org]

------- Comment #7 from pault at gcc dot gnu dot org  2006-11-22 13:42 -------
I have just submitted a patch to the gfortran list.

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|2006-11-20 15:45:09         |2006-11-22 13:42:36
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[patchapp at dberlin dot org]

------- Comment #8 from patchapp at dberlin dot org  2006-11-22 13:45 -------
Subject: Bug number PR29912

A patch for this bug has been added to the patch tracker.
The mailing list url for the patch is
http://gcc.gnu.org/ml/gcc-patches/2006-11/msg01561.html


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] Gfortran: string array functions behaving incorrectly...

[pault at gcc dot gnu dot org]

------- Comment #9 from pault at gcc dot gnu dot org  2006-12-05 19:33 -------
Subject: Bug 29912

Author: pault
Date: Tue Dec  5 19:32:59 2006
New Revision: 119554

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=119554
Log:
2006-12-05  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/29912
        * trans-expr.c (gfc_trans_arrayfunc_assign): Return NULL if the
        lhs and rhs character lengths are not constant and equal for
        character array valued functions.

2006-12-05  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/29912
        * gfortran.dg/char_result_12.f90: New test.

Added:
    trunk/gcc/testsuite/gfortran.dg/char_result_12.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/trans-expr.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] [4.2 and 4.1 only] Gfortran: string array functions behaving incorrectly...

[pault at gcc dot gnu dot org]

------- Comment #10 from pault at gcc dot gnu dot org  2006-12-09 15:17 -------
Subject: Bug 29912

Author: pault
Date: Sat Dec  9 15:17:16 2006
New Revision: 119690

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=119690
Log:
2006-12-09  Paul Thomas  <pault@gcc.gnu.org>

        Backports from trunk

        PR fortran/29821
        * resolve.c (resolve_operator): Only return result of
        gfc_simplify_expr if expression is constant.

        PR fortran/29912
        * trans-expr.c (gfc_trans_arrayfunc_assign): Return NULL if the
        lhs and rhs character lengths are not constant and equal for
        character array valued functions.

        PR fortran/29916
        * resolve.c (resolve_symbol): Allow host-associated variables
        in the specification expression of an array-valued function.
        * expr.c (check_restricted): Accept host-associated dummy
        array indices.

        PR fortran/30003
        * trans-array.c (gfc_trans_create_temp_array): Set the section
        ends to zero.
        (gfc_conv_array_transpose): Likewise.
        (gfc_conv_section_startstride): Declare an expression for end,
        set it from a the array reference and evaluate it for the info
        structure. Zero the ends in the ss structure and set end, used
        in the bounds check, from the info structure.
        trans.h: Add and end array to the gfc_ss_info structure.

2006-12-09  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/29821
        * gfortran.dg/parameter_array_section_1.f90: New test.

        PR fortran/29912
        * gfortran.dg/char_result_12.f90: New test.

        PR fortran/29916
        * gfortran.dg/host_dummy_index_1.f90: Added additional test.

        PR fortran/30003
        * gfortran.dg/allocatable_function_1.f90: Increase the number
        of expected calls of free to 10; the lhs section reference is
        now evaluated so there is another call to bar.  Change the
        comment appropriately.
        * gfortran.dg/array_section_1.f90: New test.


Added:
    branches/gcc-4_2-branch/gcc/testsuite/gfortran.dg/array_section_1.f90
    branches/gcc-4_2-branch/gcc/testsuite/gfortran.dg/char_result_12.f90
   
branches/gcc-4_2-branch/gcc/testsuite/gfortran.dg/parameter_array_section_1.f90
Modified:
    branches/gcc-4_2-branch/gcc/fortran/ChangeLog
    branches/gcc-4_2-branch/gcc/fortran/expr.c
    branches/gcc-4_2-branch/gcc/fortran/resolve.c
    branches/gcc-4_2-branch/gcc/fortran/trans-array.c
    branches/gcc-4_2-branch/gcc/fortran/trans-expr.c
    branches/gcc-4_2-branch/gcc/fortran/trans.h
    branches/gcc-4_2-branch/gcc/testsuite/ChangeLog
   
branches/gcc-4_2-branch/gcc/testsuite/gfortran.dg/allocatable_function_1.f90
    branches/gcc-4_2-branch/gcc/testsuite/gfortran.dg/host_dummy_index_1.f90


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] [4.1 only] Gfortran: string array functions behaving incorrectly...

[pault at gcc dot gnu dot org]

------- Comment #11 from pault at gcc dot gnu dot org  2006-12-09 15:21 -------
Fixed in trunk and 4.2.  If I have time, I will patch 4.1 someday.

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
            Summary|[4.2 and 4.1 only] Gfortran:|[4.1 only] Gfortran: string
                   |string array functions      |array functions behaving
                   |behaving incorrectly...     |incorrectly...


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912

[Bug fortran/29912] [4.1 only] Gfortran: string array functions behaving incorrectly...

[pault at gcc dot gnu dot org]

------- Comment #12 from pault at gcc dot gnu dot org  2006-12-09 17:48 -------
Subject: Bug 29912

Author: pault
Date: Sat Dec  9 17:47:45 2006
New Revision: 119694

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=119694
Log:
2006-12-09  Paul Thomas  <pault@gcc.gnu.org>

        Backports from trunk

        PR fortran/29821
        * resolve.c (resolve_operator): Only return result of
        gfc_simplify_expr if expression is constant.

        PR fortran/29912
        * trans-expr.c (gfc_trans_arrayfunc_assign): Return NULL if the
        lhs and rhs character lengths are not constant and equal for
        character array valued functions.

        PR fortran/29916
        * resolve.c (resolve_symbol): Allow host-associated variables
        in the specification expression of an array-valued function.
        * expr.c (check_restricted): Accept host-associated dummy
        array indices.

        PR fortran/30003
        * trans-array.c (gfc_trans_create_temp_array): Set the section
        ends to zero.
        (gfc_conv_section_startstride): Declare an expression for end,
        set it from a the array reference and evaluate it for the info
        structure. Zero the ends in the ss structure and set end, used
        in the bounds check, from the info structure.
        trans.h: Add and end array to the gfc_ss_info structure.

        PR fortran/29820
        * trans-array.c (gfc_get_derived_type): Once done, spread the
        backend_decl to all identical derived types in all sibling
        namespaces.

2006-12-09  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/29821
        * gfortran.dg/parameter_array_section_1.f90: New test.

        PR fortran/29912
        * gfortran.dg/char_result_12.f90: New test.

        PR fortran/29916
        * gfortran.dg/host_dummy_index_1.f90: Added additional test.

        PR fortran/30003
        * gfortran.dg/allocatable_function_1.f90: Increase the number
        of expected calls of free to 10; the lhs section reference is
        now evaluated so there is another call to bar.  Change the
        comment appropriately.
        * gfortran.dg/array_section_1.f90: New test.

        PR fortran/29820
        * gfortran.dg/used_types_13.f90: New test.


Added:
    branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/array_section_1.f90
    branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/char_result_12.f90
   
branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/parameter_array_section_1.f90
    branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/used_types_13.f90
Modified:
    branches/gcc-4_1-branch/gcc/fortran/ChangeLog
    branches/gcc-4_1-branch/gcc/fortran/expr.c
    branches/gcc-4_1-branch/gcc/fortran/resolve.c
    branches/gcc-4_1-branch/gcc/fortran/trans-array.c
    branches/gcc-4_1-branch/gcc/fortran/trans-expr.c
    branches/gcc-4_1-branch/gcc/fortran/trans-types.c
    branches/gcc-4_1-branch/gcc/fortran/trans.h
    branches/gcc-4_1-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/host_dummy_index_1.f90


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29912