cross compile gdb-6.8 for xtensa

[himanshu sardana <er.sardana@gmail.com>]

I am trying to remote debug an single threaded application main_app.c:

=================================================================
#include <stdio.h>

int main()
{
   int i=0;

   i++;
   printf("main_app: i=%d\n", i);

   i++;
   printf("main_app: i=%d\n", i);

   i++;
   printf("main_app: i=%d\n", i);

   return 0;
}
===================================================================

My linux machine is:
Linux ankit 2.6.18-92.el5 #1 SMP Tue Jun 10 18:49:47 EDT 2008 i686
i686 i386 GNU/Linux


STEP 1
-----------
I compiled main_app.c for xtensa on linux machine:

===================================================================
CC=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/bin/xtensa_c1lx2-linux-gcc
CFLAGS="-g -I/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/include/libxml2"
LDFLAGS="-L/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/lib"

$CC $CFLAGS -c -o main_app.o main_app.c $LDFLAGS
$CC $CFLAGS -o main_app main_app.o $LDFLAGS
===================================================================


STEP 2
-----------
I am using gdbserver on the target machine (xtensa_c1lx2-linux) and
gdb on the host machine (i686-pc-linux-gnu).

Compilation steps for gdb-6.8

========================================================================
/*configure and make gdb*/
gdb-6.8> ./configure --target=xtensa_c1lx2-linux

gdb-6.8> make

gdb-6.8> cd gdb/

gdb-6.8> ls -ltrh

/*Got gdb binary here*/


/*Now configure and make gdbserver*/
gdb-6.8> cd gdbserver/

gdb-6.8> ./configure --build=i686-pc-linux-gnu
--host=xtensa_c1lx2-linux --target=xtensa_c1lx2-linux
--includedir=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/include
 --oldincludedir=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/include
CC=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/bin/xtensa_c1lx2-linux-gcc
CFLAGS="-I/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/include/libxml2"
CXX=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/bin/xtensa_c1lx2-linux-g++
CPPFLAGS="-I/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/include/libxml2"
LDFLAGS="-L/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/lib"
STRIP=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/bin/xtensa_c1lx2-linux-strip
AR=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/bin/xtensa_c1lx2-linux-ar
RANLIB=/opt/buildroot/build_xtensa_c1lx2/staging_dir/usr/bin/xtensa_c1lx2-linux-ranlib

gdb-6.8> make

gdb-6.8> ls -ltrh

/*Got gdbserver binary here*/
========================================================================


STEP 3
------------
Transfer gdbserver and main_app on target machine and then run gdbserver

target> ./gdbserver 192.168.202.143:2108 ./main_app
Process ./main_app created; pid = 340
Listening on port 2108
Remote debugging from host 192.168.202.184


STEP 4
-----------

linux> /opt/himanshu/gdb-6.8/gdb/gdb ./main_app
GNU gdb 6.8
Copyright (C) 2008 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 "--host=i686-pc-linux-gnu
--target=xtensa_c1lx2-linux"...
(gdb) target remote 192.168.202.143:2108
Remote debugging using 192.168.202.143:2108
[New Thread 336]
0xfc140020 in ?? ()
(gdb)


After these steps if I simply 'continue' the program, the program
executes fine and then terminates properly. But, If I put a breakpoint
and then continue execution I get the following problem:

------------------------------------------------------------------------------------------------------
(gdb) b main
Breakpoint 1 at 0x4002b9: file main_app.c, line 5.
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0xc7024000 in ?? ()
(gdb) c
Continuing.

Program terminated with signal SIGSEGV, Segmentation fault.
The program no longer exists.
(gdb) q
-------------------------------------------------------------------------------------------------------


And at gdbserver side:
-------------------------------------------------------------------------------------------------------
Child terminated with signal = b

Child terminated with signal = 0xb (SIGSEGV)
GDBserver exiting
-------------------------------------------------------------------------------------------------------

What may be the problem due to which I get the above error?
Am i rightly configuring it in order to cross-compile it for xtensa?

Any suggestions will be highly appreciable.

Thanks,
Himanshu