Re: [Bug-apl] gdb and the Emacs mode segfault

[David Lamkins]

I can confirm that the update resolved the )load crashes I was seeing.

Thank you!

On May 4, 2014 12:07 AM, "Elias Mårtenson" <address@hidden> wrote:

Actually, this one was being debugged last night, with the discussion primarily being done off-list.

Please let me know if there are still problems.

Regards,

Elias

On 4 May 2014 09:27, David B. Lamkins <address@hidden> wrote:

Ah, I didn't realize I was so far behind. Thanks for the heads-up! :)

On Sun, 2014-05-04 at 08:20 +0800, Elias Mårtenson wrote:
> This was just fixed, actually. You might want to try with the latest
> version. It should work now.
>
> Regards,
> Elias
>
> On 4 May 2014 02:45, "David B. Lamkins" <address@hidden> wrote:
>         I was able to get a core dump of the segfault caused by
>         attempting to
>         )load an APL file with Emacs mode active.
>
>         address@hidden ~]$ gdb `which apl` -c core.2134
>         GNU gdb (GDB) Fedora 7.6.50.20130731-19.fc20
>         Copyright (C) 2013 Free Software Foundation, Inc.
>         License GPLv3+: GNU GPL version 3 or later
>         <http://gnu.org/licenses/gpl.html>
>         This is free software: you are free to change and redistribute
>         it.
>         There is NO WARRANTY, to the extent permitted by law.  Type
>         "show
>         copying"
>         and "show warranty" for details.
>         This GDB was configured as "x86_64-redhat-linux-gnu".
>         Type "show configuration" for configuration details.
>         For bug reporting instructions, please see:
>         <http://www.gnu.org/software/gdb/bugs/>.
>         Find the GDB manual and other documentation resources online
>         at:
>         <http://www.gnu.org/software/gdb/documentation/>.
>         For help, type "help".
>         Type "apropos word" to search for commands related to "word".
>         ..
>         Reading symbols from /usr/local/bin/apl...done.
>         [New LWP 2134]
>         [New LWP 2138]
>         [New LWP 2137]
>         [Thread debugging using libthread_db enabled]
>         Using host libthread_db library "/lib64/libthread_db.so.1".
>         Core was generated by `/usr/local/bin/apl --rawCIN --emacs'.
>         Program terminated with signal SIGSEGV, Segmentation fault.
>         #0  0x00007fd8c85b1098 in ?? () from /lib64/libgcc_s.so.1
>         Missing separate debuginfos, use: debuginfo-install
>         blas-3.4.2-3.fc20.x86_64 glibc-2.18-12.fc20.x86_64
>         lapack-3.4.2-3.fc20.x86_64 libgcc-4.8.2-7.fc20.x86_64
>         libgfortran-4.8.2-7.fc20.x86_64 libgomp-4.8.2-7.fc20.x86_64
>         libquadmath-4.8.2-7.fc20.x86_64 libstdc++-4.8.2-7.fc20.x86_64
>         ncurses-libs-5.9-12.20130511.fc20.x86_64
>         readline-6.2-8.fc20.x86_64
>         (gdb) bt
>         #0  0x00007fd8c85b1098 in ?? () from /lib64/libgcc_s.so.1
>         #1  0x00007fd8c85b1f99 in _Unwind_Backtrace ()
>         from /lib64/libgcc_s.so.1
>         #2  0x00007fd8c82e61e6 in backtrace () from /lib64/libc.so.6
>         #3  0x00000000004448a0 in Backtrace::show (
>             address@hidden "main.cc", address@hidden)
>             at Backtrace.cc:276
>         #4  0x000000000047a72a in signal_SEGV_handler () at
>         main.cc:122
>         #5  <signal handler called>
>         #6  0x00007fd8c1547730 in ?? ()
>         #7  0x0000000000476307 in Input::get_user_line (
>             prompt=0x80f230 <Workspace::the_workspace+527600>) at
>         Input.cc:223
>         #8  0x00000000004765f4 in Input::get_line () at Input.cc:150
>         #9  0x0000000000461f2d in Command::process_line () at
>         Command.cc:61
>         #10 0x0000000000522e9d in Workspace::immediate_execution
>         (exit_on_error=false)
>             at Workspace.cc:129
>         #11 0x00000000004352d5 in main (argc=3, _argv=<optimized out>)
>         at
>         main.cc:466
>         (gdb) quit
>         address@hidden ~]$
>
>         This is with svn 235.
>
>         Input.cc:223 is the (*start_input)() call:
>
>         const unsigned char *
>         Input::get_user_line(const UCS_string * prompt)
>         {
>            if (start_input)   (*start_input)();
>            ...
>
>         which, I think (determined by code inspection; not gdb),
>         points to
>         active_disable in emacs.cc. That, in turn, ultimately invokes
>         set_active():
>
>         void set_active( bool v )
>         {
>             pthread_mutex_lock( &apl_main_lock );
>             if( !apl_active && !v ) {
>                 std::cerr << "Unlocking while the lock is unlocked" <<
>         std::endl;
>                 abort();
>             }
>             if( v ) {
>                 while( apl_active ) {
>                     pthread_cond_wait( &apl_main_cond, &apl_main_lock
>         );
>                 }
>             }
>             apl_active = v;
>             pthread_cond_broadcast( &apl_main_cond );
>             pthread_mutex_unlock( &apl_main_lock );
>         }
>
>
>