[Bug fortran/40850] double free in nested types with allocatable components

[Bug fortran/40850] double free in nested types with allocatable components

[dfranke at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

Daniel Franke <dfranke at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |

--- Comment #10 from Daniel Franke <dfranke at gcc dot gnu.org> 2010-12-28 22:55:55 UTC ---
This looks like a dupe of the nested constructor case of #38319?!

[Bug fortran/40850] double free in nested types with allocatable components

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |burnus at gcc dot gnu.org

--- Comment #11 from Tobias Burnus <burnus at gcc dot gnu.org> 2011-02-21 07:32:15 UTC ---
Mikael's patch for comment 5:
http://gcc.gnu.org/ml/fortran/2011-02/msg00208.html

It does not fix comment 8; I don't know whether it fixes comment 0 or comment
4.

[Bug fortran/40850] double free in nested types with allocatable components

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

Mikael Morin <mikael at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |mikael at gcc dot gnu.org

--- Comment #12 from Mikael Morin <mikael at gcc dot gnu.org> 2011-02-21 12:57:31 UTC ---
(In reply to comment #11)
> I don't know whether it fixes comment 0 or comment 4
>
Sorry, I forgot to precise. 
It fixes neither. 
More precisely for comments 0 and 4, it does fix a read of freed memory:

==82785== Invalid read of size 8
==82785==    at 0x400F21: __mod_all_MOD_add (in
/usr/home/mik/gfortran/pr40850/comment_0)
==82785==    by 0x4023D9: MAIN__ (in /usr/home/mik/gfortran/pr40850/comment_0)
==82785==    by 0x402703: main (in /usr/home/mik/gfortran/pr40850/comment_0)
==82785==  Address 0x14be678 is 8 bytes inside a block of size 112 free'd

but doesn't fix a double free affecting comments 0, 4 and 8:

==82785== Invalid free() / delete / delete[]
==82785==    at 0x25A37E: free (in
/usr/local/lib/valgrind/vgpreload_memcheck-amd64-freebsd.so)
==82785==    by 0x402609: MAIN__ (in /usr/home/mik/gfortran/pr40850/comment_0)
==82785==    by 0x402703: main (in /usr/home/mik/gfortran/pr40850/comment_0)
==82785==  Address 0x14be3d0 is 0 bytes inside a block of size 8 free'd



Comment 8 is not affected by the invalid read as the containing entity is not
allocatable, hence not explicitly freed at the end. Thus, components release
can't happen before containing entity's release. 

For the remaining double free, the temporary for the array constructor is
filled using simple copies, and thus has components pointing to the original
array. Those components are freed by the temporary array cleanup, and again
during the final release of all allocatables. 
One could fix it by not freeing the temporary's components (no deep/nested
free), but I have the feeling (haven't completely made my mind about it) that
the proper fix, in the general case, is to create nested temporaries and do
deep copies. And yes, that would be horribly expensive :-(.

[Bug fortran/40850] double free in nested types with allocatable components

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

--- Comment #13 from Mikael Morin <mikael at gcc dot gnu.org> 2011-02-21 13:01:23 UTC ---
Comment 5 is not affected by the double free as the allocatable components are
never allocated during the program, only the containing entity is.

[Bug fortran/40850] double free in nested types with allocatable components

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

--- Comment #14 from Mikael Morin <mikael at gcc dot gnu.org> 2011-02-23 22:38:31 UTC ---
Author: mikael
Date: Wed Feb 23 22:38:27 2011
New Revision: 170445

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=170445
Log:
2011-02-23  Mikael Morin  <mikael@gcc.gnu.org>

    PR fortran/40850
    * trans.c (gfc_prepend_expr_to_block): New function.
    * trans.h (gfc_prepend_expr_to_block): Declare.
    * trans-array.c (gfc_conv_array_parameter): Replace
    gfc_add_expr_to_block with gfc_prepend_expr_to_block.

2011-02-23  Mikael Morin  <mikael@gcc.gnu.org>

    PR fortran/40850
    * gfortran.dg/nested_allocatables_1.f90: New.


Added:
    trunk/gcc/testsuite/gfortran.dg/nested_allocatables_1.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/trans-array.c
    trunk/gcc/fortran/trans.c
    trunk/gcc/fortran/trans.h
    trunk/gcc/testsuite/ChangeLog

[Bug fortran/40850] double free in nested types with allocatable components

[janus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

--- Comment #15 from janus at gcc dot gnu.org 2012-04-26 14:03:00 UTC ---
All test cases given here (comment 0, 4, 5 and 8) work with gfortran 4.6.3 and
above. I assume we can close this PR?

[Bug fortran/40850] double free in nested types with allocatable components

[b.w.barker at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

Brent W. Barker <b.w.barker at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |b.w.barker at gmail dot com

--- Comment #16 from Brent W. Barker <b.w.barker at gmail dot com> 2012-06-06 20:19:57 UTC ---
I found that the following nested deallocation program still fails in 4.6.3.
Sorry it's so long, I don't have time to think about how to shorten it right
now. It compiles and runs without error with ifort 12.1.4 20120410, and I
didn't try it with 4.7.

$ gfortran --version
GNU Fortran (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3
...

$ uname -a
Linux hostname 3.2.0-24-generic #39-Ubuntu SMP Mon May 21 16:52:17 UTC 2012
x86_64 x86_64 x86_64 GNU/Linux

$ gfortran testdealloc.F90
$ ./a.out

*** glibc detected *** ./a.out: double free or corruption (top):
0x0000000001edb0a0 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x7e626)[0x7fadbf3b1626]
./a.out[0x400fa7]
./a.out[0x401029]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed)[0x7fadbf35476d]
./a.out[0x400709]
======= Memory map: ========
00400000-00402000 r-xp 00000000 08:05 132394                            
/home/barker/sandbox/a.out
00601000-00602000 r--p 00001000 08:05 132394                            
/home/barker/sandbox/a.out
00602000-00603000 rw-p 00002000 08:05 132394                            
/home/barker/sandbox/a.out
01ed8000-01ef9000 rw-p 00000000 00:00 0                                  [heap]
7fadbebed000-7fadbec02000 r-xp 00000000 08:05 7340318                   
/lib/x86_64-linux-gnu/libgcc_s.so.1
7fadbec02000-7fadbee01000 ---p 00015000 08:05 7340318                   
/lib/x86_64-linux-gnu/libgcc_s.so.1
7fadbee01000-7fadbee02000 r--p 00014000 08:05 7340318                   
/lib/x86_64-linux-gnu/libgcc_s.so.1
7fadbee02000-7fadbee03000 rw-p 00015000 08:05 7340318                   
/lib/x86_64-linux-gnu/libgcc_s.so.1
7fadbee03000-7fadbeefc000 r-xp 00000000 08:05 7340241                   
/lib/x86_64-linux-gnu/libm-2.15.so
7fadbeefc000-7fadbf0fb000 ---p 000f9000 08:05 7340241                   
/lib/x86_64-linux-gnu/libm-2.15.so
7fadbf0fb000-7fadbf0fc000 r--p 000f8000 08:05 7340241                   
/lib/x86_64-linux-gnu/libm-2.15.so
7fadbf0fc000-7fadbf0fd000 rw-p 000f9000 08:05 7340241                   
/lib/x86_64-linux-gnu/libm-2.15.so
7fadbf0fd000-7fadbf132000 r-xp 00000000 08:05 393626                    
/usr/lib/x86_64-linux-gnu/libquadmath.so.0.0.0
7fadbf132000-7fadbf331000 ---p 00035000 08:05 393626                    
/usr/lib/x86_64-linux-gnu/libquadmath.so.0.0.0
7fadbf331000-7fadbf332000 r--p 00034000 08:05 393626                    
/usr/lib/x86_64-linux-gnu/libquadmath.so.0.0.0
7fadbf332000-7fadbf333000 rw-p 00035000 08:05 393626                    
/usr/lib/x86_64-linux-gnu/libquadmath.so.0.0.0
7fadbf333000-7fadbf4e6000 r-xp 00000000 08:05 7340313                   
/lib/x86_64-linux-gnu/libc-2.15.so
7fadbf4e6000-7fadbf6e5000 ---p 001b3000 08:05 7340313                   
/lib/x86_64-linux-gnu/libc-2.15.so
7fadbf6e5000-7fadbf6e9000 r--p 001b2000 08:05 7340313                   
/lib/x86_64-linux-gnu/libc-2.15.so
7fadbf6e9000-7fadbf6eb000 rw-p 001b6000 08:05 7340313                   
/lib/x86_64-linux-gnu/libc-2.15.so
7fadbf6eb000-7fadbf6f0000 rw-p 00000000 00:00 0 
7fadbf6f0000-7fadbf804000 r-xp 00000000 08:05 393401                    
/usr/lib/x86_64-linux-gnu/libgfortran.so.3.0.0
7fadbf804000-7fadbfa04000 ---p 00114000 08:05 393401                    
/usr/lib/x86_64-linux-gnu/libgfortran.so.3.0.0
7fadbfa04000-7fadbfa05000 r--p 00114000 08:05 393401                    
/usr/lib/x86_64-linux-gnu/libgfortran.so.3.0.0
7fadbfa05000-7fadbfa07000 rw-p 00115000 08:05 393401                    
/usr/lib/x86_64-linux-gnu/libgfortran.so.3.0.0
7fadbfa07000-7fadbfa29000 r-xp 00000000 08:05 7340317                   
/lib/x86_64-linux-gnu/ld-2.15.so
7fadbfc04000-7fadbfc08000 rw-p 00000000 00:00 0 
7fadbfc26000-7fadbfc29000 rw-p 00000000 00:00 0 
7fadbfc29000-7fadbfc2a000 r--p 00022000 08:05 7340317                   
/lib/x86_64-linux-gnu/ld-2.15.so
7fadbfc2a000-7fadbfc2c000 rw-p 00023000 08:05 7340317                   
/lib/x86_64-linux-gnu/ld-2.15.so
7fff13969000-7fff1398b000 rw-p 00000000 00:00 0                         
[stack]
7fff139d5000-7fff139d6000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                 
[vsyscall]
Aborted (core dumped)



module class_Foo
 implicit none

 type :: SubFoo
  integer :: num
 end type

 type :: Foo
  class(SubFoo), allocatable :: aSubFoo
 end type Foo

 type :: SuperFoo
  type(Foo), allocatable, dimension(:) :: foos
 end type

end module class_Foo

program testdealloc
 use class_Foo
 implicit none

 type(SuperFoo) :: mySuperFoo

 type(Foo), allocatable, dimension(:) :: myFoos

 type(SubFoo) :: mySubFoo

 mySubFoo=SubFoo(1)

 allocate(myFoos(10))

 allocate(myFoos(1)%aSubFoo, source=mySubFoo)

 mySuperFoo = SuperFoo(myFoos)

 deallocate(mySuperFoo%foos)

end program testdealloc

[Bug fortran/40850] double free in nested types with allocatable components

[janus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

--- Comment #17 from janus at gcc dot gnu.org 2012-06-06 20:58:18 UTC ---
(In reply to comment #16)
> I found that the following nested deallocation program still fails in 4.6.3.

I can confirm that it fails with 4.6.3. However, it works for me with 4.7.0 and
4.8 trunk.

[Bug fortran/40850] double free in nested types with allocatable components

[b.w.barker at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

--- Comment #18 from Brent W. Barker <b.w.barker at gmail dot com> 2012-06-09 22:48:47 UTC ---
> > I found that the following nested deallocation program still fails in 4.6.3.>
> 
> I can confirm that it fails with 4.6.3. However, it works for me with 4.7.0 and
4.8 trunk.

I confirm that it works for me with GNU Fortran (Ubuntu/Linaro 4.7.0-7ubuntu3)
4.7.0

[Bug fortran/40850] double free in nested types with allocatable components

[janus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

janus at gcc dot gnu.org changed:

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

--- Comment #19 from janus at gcc dot gnu.org 2012-10-06 21:26:30 UTC ---
Finally closing as fixed.

[Bug fortran/40850] double free in nested types with allocatable components

[dominiq at lps dot ens dot fr]

------- Comment #9 from dominiq at lps dot ens dot fr  2010-03-07 17:24 -------
I just noticed that using -Warray-temporaries gives the warning twice. For the
test in comment #8, I get

[macbook] f90/bug% gfc -Warray-temporaries -fcheck=all pr40850_3.f90
pr40850_3.f90:11.13:

  CALL test ((/ lines /))
             1
Warning: Creating array temporary at (1)
pr40850_3.f90:11.13:

  CALL test ((/ lines /))
             1
Warning: Creating array temporary at (1)
[macbook] f90/bug% a.out
a.out(35149) malloc: *** error for object 0x100201010: pointer being freed was
not allocated
*** set a breakpoint in malloc_error_break to debug
Abort


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

[Bug fortran/40850] double free in nested types with allocatable components

[domob at gcc dot gnu dot org]

------- Comment #8 from domob at gcc dot gnu dot org  2010-02-12 13:51 -------
I hit this bug, too, it seems.  My reduced test-case:

PROGRAM analysis
  IMPLICIT NONE

  TYPE numlist
    REAL, ALLOCATABLE :: nums(:)
  END TYPE numlist

  TYPE(numlist) :: lines
  ALLOCATE (lines%nums(1))

  CALL test ((/ lines /))

CONTAINS

  SUBROUTINE test (vec)
    TYPE(numlist), INTENT(IN) :: vec(:)
  END SUbROUTINE test

END PROGRAM analysis

This produces 126 lines of -fdump-tree-original, so I hope it may help here as
being "simpler" than the one posted by Janus (it seems).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

[Bug fortran/40850] double free in nested types with allocatable components

[mrestelli at gmail dot com]

------- Comment #7 from mrestelli at gmail dot com  2010-01-29 18:24 -------
(In reply to comment #5)
> Further reduced test case:
> 
> 
>   type t
>     integer, allocatable :: d(:)
>   end type
>   type(t), allocatable :: a(:)
> 
>   allocate(a(2))
>   call sub( (/ a /) )
> 
> contains
> 
>   subroutine sub(b)
>     type(t) :: b(:)
>   end subroutine
> 
> end
> 
> 
> The dump still has more than 200 lines and five __builtin_free's.
> 


Not sure if this is correct or useful, since I don't know the gfortran
internals at all, but anyway, mostly out of curiosity: my impression
is that the problem is in the lines 187-222 of the
-fdump-tree-original output file. More precisely (starting with line
186):


    sub (&atmp.6);
Here we free atmp.3.data (without worrying about the allocation status
of the elements)
    {
      void * D.1574;

      D.1574 = (void *) atmp.3.data;
      if (D.1574 != 0B)
        {
          __builtin_free (D.1574);
        }
    }
Here we free atmp.6.data (again, without worrying about the allocation
status of the elements)
    {
      void * D.1593;

      D.1593 = (void *) atmp.6.data;
      if (D.1593 != 0B)
        {
          __builtin_free (D.1593);
        }
    }
Now we look at the elements of atmp.6.data to check whether we have to
free them too. It seems to the me that this block should be moved
before the previous one (or eliminated at all, as it is done for
atmp.3.data)
    if ((struct t[0:] * restrict) atmp.6.data != 0B)
      {
        D.1596 = (atmp.6.dim[0].ubound - atmp.6.dim[0].lbound) + 1;
        D.1597 = atmp.6.dim[0].stride * D.1596;
        D.1598 = D.1597 + -1;
        S.8 = 0;
        while (1)
          {
            if (S.8 > D.1598) goto L.5;
Here we access memory that has already been freed
            if ((*(struct t[0:] * restrict) atmp.6.data)[S.8].d.data != 0B)
              {
                __builtin_free ((void *) (*(struct t[0:] * restrict)
atmp.6.data)[S.8].d.data);
              }
            (*(struct t[0:] * restrict) atmp.6.data)[S.8].d.data = 0B;
            S.8 = S.8 + 1;
          }
        L.5:;
      }


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

[Bug fortran/40850] double free in nested types with allocatable components

[pault at gcc dot gnu dot org]

------- Comment #6 from pault at gcc dot gnu dot org  2010-01-07 14:49 -------
I had better add this to the 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|REOPENED                    |ASSIGNED
   Last reconfirmed|2009-12-07 21:00:41         |2010-01-07 14:49:06
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

[Bug fortran/40850] double free in nested types with allocatable components

[janus at gcc dot gnu dot org]

------- Comment #5 from janus at gcc dot gnu dot org  2009-12-07 21:00 -------
Further reduced test case:


  type t
    integer, allocatable :: d(:)
  end type
  type(t), allocatable :: a(:)

  allocate(a(2))
  call sub( (/ a /) )

contains

  subroutine sub(b)
    type(t) :: b(:)
  end subroutine

end


The dump still has more than 200 lines and five __builtin_free's.


-- 

janus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |janus at gcc dot gnu dot org
   Last reconfirmed|2009-12-06 18:15:24         |2009-12-07 21:00:41
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850

[Bug fortran/40850] double free in nested types with allocatable components

[dfranke at gcc dot gnu dot org]

------- Comment #4 from dfranke at gcc dot gnu dot org  2009-12-06 18:15 -------
Reduced testcase:

  type t1
    integer, allocatable :: d1(:)
  end type t1
  type t2
    type(t1), allocatable :: d2(:)
  end type t2
  type(t2) :: a, b

  a = new2( (/ new1((/1,1/)) /) )
  b = new2( (/ a%d2 , a%d2 /) )

contains
  pure type(t1) function new1(d1)
    integer, intent(in) :: d1(:)
    allocate(new1%d1(size(d1)))
    new1%d1 = d1
  end function
  pure type(t2) function new2(d2)
    type(t1), intent(in) :: d2(:)
    allocate(new2%d2(size(d2)))
    new2%d2 = d2
  end function
end

The dump still has about 800 lines - somewhat hard to tell what's going on.
Adding PaulT as CC.


-- 

dfranke at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dfranke at gcc dot gnu dot
                   |                            |org, pault at gcc dot gnu
                   |                            |dot org
   Last reconfirmed|2009-07-25 07:32:47         |2009-12-06 18:15:24
               date|                            |
            Summary|"double free or corruption" |double free in nested types
                   |returning derived types with|with allocatable components
                   |allocatable components      |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40850