In case there is a native GDB available for your target you can use
it for application debugging as usual:
bash$ gcc -Wall -g -o hello hello.c
bash$ gdb hello
...
(gdb) l
1 #include <stdio.h>
2
3 int main(int argc, char* argv[])
4 {
5 printf ("Hello world\n");
6 return 0;
7 }
(gdb) break 5
Breakpoint 1 at 0x8048466: file hello.c, line 5.
(gdb) run
Starting program: /opt/eldk/ppc_8xx/tmp/hello
Breakpoint 1, main (argc=0x1, argv=0xbffff9f4) at hello.c:5
5 printf ("Hello world\n");
(gdb) c
Continuing.
Hello world
Program exited normally.
gdbserver allows you to connect your program with
a remote GDB using the "target remote" command. On the target
machine, you need to have a copy of the program you want to debug.
gdbserver does not need your program's symbol
table, so you can strip the program if necessary to save space.
GDB on the host system does all the symbol
handling. Here is an example:
bash$ ${CROSS_COMPILE}gcc -Wall -g -o hello hello.c
bash$ cp -p hello <directory-shared-with-target>/hello-stripped
bash$ ${CROSS_COMPILE}strip <directory-shared-with-target>/hello-stripped
To use the server, you must tell it how to communicate with
GDB, the
name of your program, and the arguments for your program. To start a
debugging session via network type on the target:
bash$ cd <directory-shared-with-host>
bash$ gdbserver 192.168.1.1:12345 hello-stripped
Process hello-stripped created; pid = 353
And then on the host:
bash$ ${CROSS_COMPILE}gdb hello
...
(gdb) set solib-absolute-prefix /opt/eldk/$CROSS_COMPILE
(gdb) dir /opt/eldk/$CROSS_COMPILE
Source directories searched:
/opt/eldk/$CROSS_COMPILE:$cdir:$cwd
(gdb) target remote 192.168.1.99:12345
Remote debugging using 192.168.1.99:12345
0x30012748 in ?? ()
...
(gdb) l
1 #include <stdio.h>
2
3 int main(int argc, char* argv[])
4 {
5 printf ("Hello world\n");
6 return 0;
7 }
(gdb) break 5
Breakpoint 1 at 0x10000498: file hello.c, line 5.
(gdb) continue
Continuing.
Breakpoint 1, main (argc=1, argv=0x7ffffbe4) at hello.c:5
5 printf ("Hello world\n");
(gdb) p argc
$1 = 1
(gdb) continue
Continuing.
Program exited normally.
If the target program you want to debug is linked against shared
libraries, you
must tell GDB where the proper target libraries are
located. This is done using the
set solib-absolute-prefix GDB
command. If this command is omitted, then, apparently, GDB loads the
host versions of the libraries and gets crazy because of that.
