How to debug xfree86 successfully

Dear All:

  I want to trace the behaviors of my video driver under Xfree86 and 

have done the following steps which were collected from this mailing list.

 

1. prepare two machines; one is called host, and another is called target.

2. type "makeg World" under "xc" folder 

3. telnet the target from host and run "gdb /usr/X11R6/bin/XFree86"

4. under the gdb command mode type "run :0"

 

Here my question comes from. I type "list" under gdb command mode.

I saw the source code of XFree86, main.c, but if I set the breakpoint 

about the driver functions such as Probe, ScreenInit and EnterVT, which are 

assigned to pScrn. The gdb told me that he cannot find the symbol file.

 

Are there some steps between 1-4 I made wrong or in fact I didn't build the
symbol 

file correctly? 

 

By the way, while manning gdb, I saw another way to build remote-debug by 

using gdbserver.

Below are the steps excerpted from the document:

(here I use com1 for example)

1. target: #gdbserver /dev/ttyS0 exe-command argument 

2. host  : #gdb 

3. host  : #gdb> target remote /dev/ttyS0

Both sides are waiting for awhile, and then it say "Ignoring packet error,
continuing..."

ps:I have check the com1 port is well-functional.

 

Any suggestion will be appreciated.

 

Thanks a lot