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| author | Yao Qi <yao.qi@linaro.org> | 2015-07-17 12:14:59 +0100 |
|---|---|---|
| committer | Yao Qi <yao.qi@linaro.org> | 2015-07-17 12:14:59 +0100 |
| commit | 6a49a997b406fba3a389d9d8a6ff72042606c69d (patch) | |
| tree | 8a42a23273614e04cbb0b845db97c8d04a97215e | |
| parent | 4f9b735feac07e013e9f63d50d9da7a91d58cdfe (diff) | |
| download | gdb-6a49a997b406fba3a389d9d8a6ff72042606c69d.zip gdb-6a49a997b406fba3a389d9d8a6ff72042606c69d.tar.gz gdb-6a49a997b406fba3a389d9d8a6ff72042606c69d.tar.bz2 | |
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:
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.
| -rw-r--r-- | gdb/ChangeLog | 5 | ||||
| -rw-r--r-- | gdb/remote.c | 4 |
2 files changed, 7 insertions, 2 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index f4857e3..646a827 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +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. + 2015-07-16 Pierre Langlois <pierre.langlois@arm.com> * aarch64-tdep.c (aarch64_pseudo_read_value): Mark S register as diff --git a/gdb/remote.c b/gdb/remote.c index 9d97f6b..94899bd 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -3474,7 +3474,7 @@ stop_reply_extract_thread (char *stop_reply) 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 @@ -3503,7 +3503,7 @@ add_current_inferior_and_thread (char *wait_status) { struct remote_state *rs = get_remote_state (); int fake_pid_p = 0; - ptid_t ptid = null_ptid; + ptid_t ptid; inferior_ptid = null_ptid; |