Re: Patch to propagate GDB's knowledge of the executing state to frontend

[ali_anwar <ali_anwar@codesourcery.com>]

On 10/30/2012 04:52 PM, ali_anwar wrote:
> On 10/30/2012 11:20 AM, Yao Qi wrote:
>> On 10/25/2012 07:09 PM, ali_anwar wrote:
>>> Hi,
>>>
>>> Attached patch is to let GDB propagate the target state under following
>>> two scenarios:
>>>
>>> 1. Attached patch will enable GDB to inform about the state of the
>>> target when it was not able to fetch the non-general registers, when
>>> target is already stopped.
>>>
>>> The reason behind this behavior was an error message which was caused
>>> when the GDB was not able to fetch the value of a certain register. The
>>> GDB should have told the front end about the current state of the
>>> target. The attached patch makes sure that it happens. This patch should
>>> be a safety measure in case some debugging stub behaves badly.
>>>
>>> 2. Attached patch will enable GDB to inform about the state of the
>>> target when it was not able to fetch the backtrace once the step has
>>> already occurred and target is in stopped state.
>>>
>>
>> It is better to describe what will happen or what is wrong if this patch
>> is not applied.
>>
>
> Thanks Yao for the review. Let me restate the actual problem:
>
> Under certain scenarios, GDB is unable to specify the correct target
> state once the step/finish instruction is executed.
>
> 1. If you perform a step out (finish) and there is an error when GDB
> tries to fetch the register values.
>
> 2. If you perform a ste and there is an error when GDB tries to fetch
> the backtrace.
>
> In both the cases the only output is an error message and nothing is
> printed as far as current target state is concerned.e.g.
>
>
> (gdb)
> -exec-finish
> ^running
> *running,thread-id="all"
> (gdb)
> ^error,msg="Could not fetch register \"\"; remote failure reply 'E22'"
> (gdb)
>
>
> In other words from MI's perspective, the step hasn't completed yet –
> the state is still "running".
>
> The only concern is GDB not printing the state of the target. It does
> not matter why the error occurred.
>
>>> + executing state to frontend when not able to fetch registers.
>>> + (wait_for_inferior): Chnage to propagate GDB's knowledge of
>> ^^^^^^ typo
>>
>>
>>> + the executing state if not able to fetch backtrace once the
>>> + step has already occured.
>> ^^^^^^^ typo.
>>
>
> I will fix the both typos.
>
>> In each changelog entry, we'll put 'what do we change' instead of 'why
>> do we change in this way'. So this entry can be simplified.
>>
>
> I will look into it as well.
>
>>> + handle_inferior_event (ecs);
>>> + return (0);
>>
>> parentheses are not needed.
>>
>>> +}
>>> +
>>> + return (0);
>>
>> Likewise.
>>
>
> I will remove the parentheses.
>
>

Ping.. Is it OK to commit?

-Ali