This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
Re: [PATCH v7 3/8] Use xml-syscall to compare syscall numbers in arm_linux_sigreturn_return-addr.
- From: Pedro Alves <palves at redhat dot com>
- To: Antoine Tremblay <antoine dot tremblay at ericsson dot com>, Yao Qi <qiyaoltc at gmail dot com>
- Cc: gdb-patches at sourceware dot org
- Date: Fri, 11 Dec 2015 12:47:38 +0000
- Subject: Re: [PATCH v7 3/8] Use xml-syscall to compare syscall numbers in arm_linux_sigreturn_return-addr.
- Authentication-results: sourceware.org; auth=none
- References: <1449583641-18156-1-git-send-email-antoine dot tremblay at ericsson dot com> <1449583641-18156-4-git-send-email-antoine dot tremblay at ericsson dot com> <86io45ql3x dot fsf at gmail dot com> <566ABA91 dot 5000508 at redhat dot com> <566ABB44 dot 3080004 at gmail dot com> <566ABC0C dot 10101 at redhat dot com> <566AC23B dot 6060800 at ericsson dot com>
On 12/11/2015 12:31 PM, Antoine Tremblay wrote:
>
>
> On 12/11/2015 07:05 AM, Pedro Alves wrote:
>> On 12/11/2015 12:02 PM, Yao Qi wrote:
>>> On 11/12/15 11:59, Pedro Alves wrote:
>>>> but then you might as well just do:
>>>>
>>>> #define ARM_SIGRETURN 119
>>>
>>> How about using __NR_sigreturn and __NR_rt_sigreturn directly? like
>>> what patch #6 does.
>>
>> Those are host/native macros. Only make sense for the running host.
>> Can't use that in a tdep file, like arm-linux-tdep.c. Otherwise, e.g.,
>> a x86-hosted cross debugger would be using the x86 __NR_sigreturn, etc.
>>
>
> Exactly that's why I use those only in GDBServer.
Hmm, actually, that sounds wrong.
What about Aarch64 gdbserver debugging Aarch32?
I see that the new code in question in patch #6 is in gdbserver/linux-arm-low.c,
which is not built on Aarch64, but, shouldn't that new arm_sigreturn_next_pc
code be used in the biarch scenario as well?
If you just made that 32-bit-specific code compile on Aarch64 it would
be compiling against Aarch64's __NR_sigreturn, which I'd assume is wrong for Aarch32.
>
> Personally while I like the #define ARM_SIGRETURN 119 better, I think
> the xml function is fine.
>
If you added
#define ARM_LINUX_SIGRETURN 119
to arch/arm-linux.h
you could use it in both places.
Thanks,
Pedro Alves