Fix error when gdb connect to a stub that tracepoint is running[1/2] Add a flag initialized to struct trace_status

[Hui Zhu <hui_zhu at mentor dot com>]

Hi Pedro,

After discussion with Yao in irc, our thought is if we want handle it in 
update_global_location_list, there will a lot of part need to be change, 
because there are a lot of call level.  For example:
#0  remote_download_tracepoint (loc=0x35040b0) at 
../../src/gdb/remote.c:9982
#1  0x00000000006727c1 in download_tracepoint_locations () at 
../../src/gdb/breakpoint.c:10670
#2  0x0000000000673111 in update_global_location_list (should_insert=1) 
at ../../src/gdb/breakpoint.c:11021
#3  0x0000000000663752 in create_overlay_event_breakpoint () at 
../../src/gdb/breakpoint.c:2322
#4  0x0000000000675c9f in breakpoint_re_set () at 
../../src/gdb/breakpoint.c:12621
#5  0x00000000007efe65 in solib_add (pattern=0x0, from_tty=1, 
target=0x1d1e860, readsyms=1)
     at ../../src/gdb/solib.c:928
#6  0x000000000057b452 in enable_break (info=0x3307890, from_tty=1) at 
../../src/gdb/solib-svr4.c:1624
#7  0x000000000057c428 in svr4_solib_create_inferior_hook (from_tty=1) 
at ../../src/gdb/solib-svr4.c:2234
#8  0x00000000007f04a9 in solib_create_inferior_hook (from_tty=1) at 
../../src/gdb/solib.c:1172
#9  0x00000000006cc8e5 in post_create_inferior (target=0x1d1e860, 
from_tty=1) at ../../src/gdb/infcmd.c:431
#10 0x00000000006d479d in start_remote (from_tty=1) at 
../../src/gdb/infrun.c:2309
#11 0x00000000005d80c9 in remote_start_remote (from_tty=1, 
target=0x1cefce0, extended_p=0)
     at ../../src/gdb/remote.c:3367

The idea of this patch is let remote_get_trace_status doesn't try to 
access to target status before remote_start_remote call 
remote_get_trace_status.  Then when GDB call 
download_tracepoint_locations try to download tracepoint before call 
remote_get_trace_status, it will got !ts->running_known in 
remote_can_download_tracepoint.  Then GDB will not download tracepoint 
before remote_start_remote call remote_get_trace_status.

BTW, to handle this issue we need patch in
http://sourceware.org/ml/gdb-patches/2012-01/msg01008.html too.

Thanks,
Hui

2012-02-27  Hui Zhu  <hui_zhu@mentor.com>
	    Yao Qi  <yao@codesourcery.com>

	* remote.c (remote_start_remote): ts->initialized to false in the
	begin of this function and set it to true before
	call remote_get_trace_status.
	(remote_get_trace_status): Return directly if ts->initialized is false.
	tracepoint.c(tfile_open): Set ts->initialized to true.
	tracepoint.h(trace_status): Add initialized.

Attachment: reset-trace-status.txt
Description: Text document