[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

--- Comment #14 from Thomas Koenig  ---
Author: tkoenig
Date: Sun Feb 28 22:27:55 2016
New Revision: 233797

URL: https://gcc.gnu.org/viewcvs?rev=233797=gcc=rev
Log:
2016-02-28  Thomas Koenig  

PR fortran/68147
PR fortran/47674
* frontend-passes.c (realloc_string_callback): Don't set
walk_subtrees.

2016-02-28  Thomas Koenig  

PR fortran/68147
PR fortran/47674
* gfortran.dg/realloc_on_assign_26.f90:  New test case.


Added:
trunk/gcc/testsuite/gfortran.dg/realloc_on_assign_26.f90
Modified:
trunk/gcc/fortran/ChangeLog
trunk/gcc/fortran/frontend-passes.c
trunk/gcc/testsuite/ChangeLog

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

Thomas Koenig tkoenig at gcc dot gnu.org changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 Resolution|--- |FIXED

--- Comment #13 from Thomas Koenig tkoenig at gcc dot gnu.org ---
Fixed, as nobody expressed interest in further backporting.

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

--- Comment #12 from Thomas Koenig tkoenig at gcc dot gnu.org ---
Is there interesting in further backporting?

If not, I would close this as fixed.

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

--- Comment #10 from Thomas Koenig tkoenig at gcc dot gnu.org ---
Author: tkoenig
Date: Mon Jan  5 17:15:17 2015
New Revision: 219193

URL: https://gcc.gnu.org/viewcvs?rev=219193root=gccview=rev
Log:
2015-01-05  Thomas Koenig  tkoe...@gcc.gnu.org

PR fortran/47674
* dependency.c:  Update copyright years.
(gfc_discard_nops):  Add prototype.
* dependency.c (discard_nops):  Rename to gfc_discard_nops,
make non-static.
(gfc_discard_nops):  Use gfc_discard_nops.
(gfc_dep_difference):  Likewise.
* frontend-passes.c  Update copyright years.
(realloc_strings):  New function.  Add prototype.
(gfc_run_passes):  Call realloc_strings.
(realloc_string_callback):  New function.
(create_var):  Add prototype.  Handle case of a
scalar character variable.
(optimize_trim):  Do not handle allocatable variables.

2015-01-05  Thomas Koenig  tkoe...@gcc.gnu.org

PR fortran/47674
* gfortran.dg/realloc_on_assign_25.f90:  New test.

Added:
trunk/gcc/testsuite/gfortran.dg/realloc_on_assign_25.f90
Modified:
trunk/gcc/fortran/ChangeLog
trunk/gcc/fortran/dependency.c
trunk/gcc/fortran/frontend-passes.c
trunk/gcc/testsuite/ChangeLog

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

--- Comment #11 from Thomas Koenig tkoenig at gcc dot gnu.org ---
Author: tkoenig
Date: Mon Jan  5 19:21:12 2015
New Revision: 219195

URL: https://gcc.gnu.org/viewcvs?rev=219195root=gccview=rev
Log:
2015-01-05  Thomas Koenig  tkoe...@gcc.gnu.org

PR fortran/47674
* dependency.h:  Actually commit changes.



Modified:
trunk/gcc/fortran/ChangeLog
trunk/gcc/fortran/dependency.h

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

Thomas Koenig tkoenig at gcc dot gnu.org changed:

   What|Removed |Added

   Assignee|unassigned at gcc dot gnu.org  |tkoenig at gcc dot 
gnu.org

--- Comment #9 from Thomas Koenig tkoenig at gcc dot gnu.org ---
I have a patch (not a pretty one, though).

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

Bernd Edlinger bernd.edlinger at hotmail dot de changed:

   What|Removed |Added

 CC||bernd.edlinger at hotmail dot 
de

--- Comment #8 from Bernd Edlinger bernd.edlinger at hotmail dot de ---
Hmm...,

I just noticed, that it also fails if MALLOC_CHECK_ is defined,
although MALLOC_PERTURB_=237 without MALLOC_CHECK_ does nothing.

$ gfortran realloc_on_assign_5.f03
$ MALLOC_CHECK_=3 ./a.out 

Program aborted. Backtrace:
#0  0x7F46086BB307
#1  0x7F46086BC9E2
#2  0x7F460878E6D8
#3  0x400C0B in MAIN_

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

Thomas Koenig tkoenig at gcc dot gnu.org changed:

   What|Removed |Added

 CC||tkoenig at gcc dot gnu.org

--- Comment #7 from Thomas Koenig tkoenig at gcc dot gnu.org ---
*** Bug 60542 has been marked as a duplicate of this bug. ***

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

--- Comment #6 from Dominique d'Humieres dominiq at lps dot ens.fr ---
gfortran.dg/realloc_on_assign_5.f03 also fails at run time when compiled with 
-fsanitize=address.

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

Dominique d'Humieres dominiq at lps dot ens.fr changed:

   What|Removed |Added

 CC||howarth at nitro dot med.uc.edu

--- Comment #5 from Dominique d'Humieres dominiq at lps dot ens.fr ---
*** Bug 55484 has been marked as a duplicate of this bug. ***

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

Dominique d'Humieres dominiq at lps dot ens.fr changed:

   What|Removed |Added

 Status|UNCONFIRMED |NEW
   Last reconfirmed||2013-06-16
 Ever confirmed|0   |1

--- Comment #4 from Dominique d'Humieres dominiq at lps dot ens.fr ---
Confirmed.

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674



Thomas Koenig tkoenig at gcc dot gnu.org changed:



   What|Removed |Added



 CC||dominiq at lps dot ens.fr



--- Comment #3 from Thomas Koenig tkoenig at gcc dot gnu.org 2013-04-08 
20:25:49 UTC ---

*** Bug 56594 has been marked as a duplicate of this bug. ***

[Bug fortran/47674] gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47674

--- Comment #2 from Tobias Burnus burnus at gcc dot gnu.org 2011-08-03 
07:23:18 UTC ---
The problem seems to be that for strings, the dependency resolver does not
trigger: as there are no strides, certain dependencies are already handled, but
it fails if the LHS/RHS variables are the same and LHS is reallocated because
of a different (shorter) string length.

dependency.c's gfc_dep_resolver has:

case REF_SUBSTRING:
  /* Substring overlaps are handled by the string assignment code
 if there is not an underlying dependency.  */
  return (fin_dep == GFC_DEP_OVERLAP) ? 1 : 0;

which returns 0 for:

  string = string(1:2) ! Issue: Realloc without temporary

trans-expr.c's alloc_scalar_allocatable_for_assignment handles scalars, where
the value might bet wrong.

A similar issue exists for arrays, though here there are provisions for adding
temporaries. (Cf. also trans-array.c's gfc_alloc_allocatable_for_assignment.)

I am not quite sure whether which if any part should be handled in the
depenedency analysis and which in the assignment code. At least the scalar
assignment code does not seem provide for temporaries at all.


A related issue is PR 49954: ICE with concatenated array strings.