Fix using uninitialised values
We did a code refacotr here
https://sourceware.org/ml/gdb-patches/2013-11/msg00063.html
> (get_current_thread): New function, factored out from ...
> (add_current_inferior_and_thread): ... this. Adjust.
>
>@@ -3332,18 +3371,8 @@ add_current_inferior_and_thread (char *wait_status)
>
> inferior_ptid = null_ptid;
>
>- /* Now, if we have thread information, update inferior_ptid. First
>- if we have a stop reply handy, maybe it's a T stop reply with a
>- "thread" register we can extract the current thread from. If
>- not, ask the remote which is the current thread, with qC. The
>- former method avoids a roundtrip. Note we don't use
>- remote_parse_stop_reply as that makes use of the target
>- architecture, which we haven't yet fully determined at this
>- point. */
>- if (wait_status != NULL)
>- ptid = stop_reply_extract_thread (wait_status);
>- if (ptid_equal (ptid, null_ptid))
>- ptid = remote_current_thread (inferior_ptid);
>+ /* Now, if we have thread information, update inferior_ptid. */
>+ ptid = get_current_thread (wait_status);
but after the refactor, local variable ptid is used without
initialisation. However, before this change, ptid is initialised to
null_ptid. This error can be found by valgrind too...
==3298== at 0x6B99BA: ptid_equal (ptid.c:80)
==3298== by 0x4C67FF: get_current_thread (remote.c:3484)
==3298== by 0x4C6951: add_current_inferior_and_thread (remote.c:3511)
==3298== by 0x4C762C: extended_remote_create_inferior (remote.c:8506)
==3298== by 0x5A5312: run_command_1 (infcmd.c:606)
==3298== by 0x68B4FB: execute_command (top.c:463)
==3298== by 0x5C7214: command_handler (event-top.c:494)
==3298== by 0x5C78A3: command_line_handler (event-top.c:692)
==3298== by 0x6DEB57: rl_callback_read_char (callback.c:220)
==3298== by 0x5C7278: rl_callback_read_char_wrapper (event-top.c:171)
==3298== by 0x5C72C2: stdin_event_handler (event-top.c:432)
==3298== by 0x5C6194: gdb_wait_for_event (event-loop.c:834)
This patch initialises local variable ptid to null in get_current_thread.
We don't need to initialise ptid in add_current_inferior_and_thread,
so this patch also removes the ptid initialisation.
gdb/ChangeLog.arm:
2016-03-29 Andre Vieira <andre.simoesdiasvieira@arm.com>
Backport from mainline
2015-07-17 Yao Qi <yao.qi@linaro.org>
* remote.c (get_current_thread): Initialise ptid to null_ptid.
(add_current_inferior_and_thread): Don't initialise ptid.
diff --git a/gdb/ChangeLog.arm b/gdb/ChangeLog.arm
index da444fd..e3b3255 100644
--- a/gdb/ChangeLog.arm
+++ b/gdb/ChangeLog.arm
@@ -1,3 +1,8 @@
+2016-03-29 Andre Vieira <andre.simoesdiasvieira@arm.com>
+ Backport from mainline
+ 2015-07-17 Yao Qi <yao.qi@linaro.org>
+ * remote.c (get_current_thread): Initialise ptid to null_ptid.
+ (add_current_inferior_and_thread): Don't initialise ptid.
2016-02-16 Andre Vieira <andre.simoesdiasvieira@arm.com>
Backport from mainline
2016-02-04 Yao Qi <yao.qi@linaro.org>
diff --git a/gdb/remote.c b/gdb/remote.c
index 2ce2932..bc6bacf 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -3507,7 +3507,7 @@
static ptid_t
get_current_thread (char *wait_status)
{
- ptid_t ptid;
+ ptid_t ptid = null_ptid;
/* Note we don't use remote_parse_stop_reply as that makes use of
the target architecture, which we haven't yet fully determined at
@@ -3536,7 +3536,7 @@
{
struct remote_state *rs = get_remote_state ();
int fake_pid_p = 0;
- ptid_t ptid = null_ptid;
+ ptid_t ptid;
inferior_ptid = null_ptid;
