GFORTRAN_CONVERT_UNIT not working for me in some situations

[Shane Hart]

I have a program that reads and writes several large files in big endian format 
on several predefined file units.  Since I'm using a little-endian system 
(x86_64) there is code some of the wrapper utilities that set 
GFORTRAN_CONVERT_UNIT to big endian for these units.  Relevent script fragment 
below:

  # gfortran compiler
    export GFORTRAN_CONVERT_UNIT='native;big_endian:60-70,80-89'

However, whenever any Fortran program is started with this set, it causes:

malloc.c:2368: sysmalloc: Assertion `(old_top == (((mbinptr) (((char *) 
&((av)->bins[((1) - 1) * 2])) - __builtin_offsetof (struct malloc_chunk, fd)))) 
&& old_size == 0) || ((unsigned long) (old_size) >= (unsigned long)
((((__builtin_offsetof (struct malloc_chunk, fd_nextsize))+((2 * 
(sizeof(size_t))) - 1)) & ~((2 * (sizeof(size_t))) - 1))) && ((old_top)->size 
& 0x1) && ((unsigned long)old_end & pagemask) == 0)' failed.
Aborted

This has been tested on (and fails):

Arch Linux (GCC 4.7.1) - 32 bit
Arch Linux (GCC 4.7.2) - 32 bit
Arch Linux (GCC 4.7.1) - 64 bit
Ubuntu 12.04 (GCC 4.6.3) - 64 bit
Linux Mint 13 (GCC 4.6.3) - 32 bit
Ubuntu 12.10 Beta 1 (GCC 4.7.2) - 32 bit
OpenSUSE 12.2 (GCC 4.7.1) - 32 bit

However, the program runs successfully on:

Fedora 17 (GCC 4.7.0) - 64 bit
Fedora 17 (GCC 4.7.2) - 64 bit
Fedora 18 Alpha (GCC 4.7.2) - 32 bit

To further test I wrote a simple program that writes "Hello World!" to the 
screen and ran it like thus:

[shane@shane-laptop ~/temp/testgfortran]$ gfortran --version
GNU Fortran (GCC) 4.7.1 20120721 (prerelease)
Copyright (C) 2012 Free Software Foundation, Inc.

GNU Fortran comes with NO WARRANTY, to the extent permitted by law.
You may redistribute copies of GNU Fortran
under the terms of the GNU General Public License.
For more information about these matters, see the file named COPYING

[shane@shane-laptop ~/temp/testgfortran]$ cat fake.f90
program fake
print*, 'hello world!'
end program fake
[shane@shane-laptop ~/temp/testgfortran]$ gfortran -o fake fake.f90
[shane@shane-laptop ~/temp/testgfortran]$ ./fake
 hello world!
[shane@shane-laptop ~/temp/testgfortran]$ 
GFORTRAN_CONVERT_UNIT='native;big_endian:88' ./fake
fake: malloc.c:2368: sysmalloc: Assertion `(old_top == (((mbinptr) (((char *) 
&((av)->bins[((1) - 1) * 2])) - __builtin_offsetof (struct malloc_chunk, fd)))) 
&& old_size == 0) || ((unsigned long) (old_size) >= (unsigned long)
((((__builtin_offsetof (struct malloc_chunk, fd_nextsize))+((2 * 
(sizeof(size_t))) - 1)) & ~((2 * (sizeof(size_t))) - 1))) && ((old_top)->size 
& 0x1) && ((unsigned long)old_end & pagemask) == 0)' failed.
Aborted
[shane@shane-laptop ~/temp/testgfortran]$

However, this does seem to work on Debian testing.

According to the GNU GFortran manual at: 
http://gcc.gnu.org/onlinedocs/gcc-4.7.2/gfortran/GFORTRAN_005fCONVERT_005fUNIT.html 
this is the correct way to do this.  I can't believe that this is a bug since 
it affects so many distributions/versions, so I must be doing something wrong.  
Any ideas on how to specify the endianness for certain Fortran units without 
changing the source?  (convert='big_endian' does seem to work, but right now I 
can't change the huge monolithic program).

Thanks for any help,
Shane Hart