[patch, fortran] PR77828 Linking gfortran-7 compiled program with libgfortran of 5.x allowed but crashes

[Jerry DeLisle]

Ping (shall I proceed)

On 10/18/2016 04:48 PM, Jerry DeLisle wrote:
> Hi Folks,
>
> The attached patch does some minor cleanup and bumps the libgfortran version
> number.  I have wanted to reorder the dtp structure for many years now. Not
> strictly needed but it has bugged me forever.
>
> The bump is needed because of the significant changes from implementation of DTIO.
>
> I also took care of the stream I/O TODO and added a new test case for the error
> message.
>
> On my system, I have LD_LIBRARY_PATH set to point to the new library version
> first and then the version 3 are found elsewhere. With the patch we now see the
> following behavior. (Test case in the PR)
>
> Compile with version 6. Finds libgfortran3 on execution:
> $gfc6 pr77828.f90
> $ ./a.out
>  Greetings from i 42 of 43
>
>  Greetings from i 42 of 43
>
> Compile with version 7. Finds libgfortran4 on execution:
> $ gfc pr77828.f90
> [jerry@amda8 pr77828]$ ./a.out
>  Greetings from i 42 of 43
>
>  Greetings from i 42 of 43
>
> Change LD_LIBRARY_PATH to not find libgfortran4:
> $ export LD_LIBRARY_PATH=/home/jerry/dev/usr6/lib64
> $ gfc pr77828.f90
> $ ./a.out
> ./a.out: error while loading shared libraries: libgfortran.so.4: cannot open
> shared object file: No such file or directory
>
> Word of caution. When this patch is applied rebuild from a clean/empty build
> directory. You must delete any libgfortran3 remnants that may have been built
> and installed previously with gcc version 7 trunk, Otherwise the linker/loader
> may find those rather than a libgfortran3 built for gcc 6 or previous. (When
> compiling with a previous version of gcc)
>
> New test case provided for the streamio error check.
>
> Regression tested on x86-64-linux.
>
> OK for trunk?
>
> Regards,
>
> Jerry
>
> 2016-10-18  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
>
>     PR fortran/77828
>     * io/io.h (st_parameter_dt): Reorder for readability and sanity.
>     * io/transfer.c (data_transfer_init): Remove TODO and enable the
>     runtime error message, rec= specifier not allowed in STREAM
>     access.
>     * libtool-version: Bump major version of libgfortran to 4.
>
> 2016-10-18  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
>
>     PR fortran/77828
>     * ioparm.def: Reorder dt parameters to match libgfortran.
>
>
>