Re: Behaviour of invalid varobjs

[Vladimir Prus <ghost@cs.msu.su>]

On Thursday 22 March 2007 13:32, Nick Roberts wrote:
>  > I think current mainline does something strange
>  > about varobjs that cannot be evaluated:
>  > 
>  >         -var-create null_ptr * **0
>  >         ^done,name="null_ptr",numchild="0",value="0",type="int"
>  >         (gdb)
>  >         -var-update null_ptr
>  >         ^done,changelist=[{name="null_ptr",in_scope="false"}]
>  > 
>  > First, the value of "**0" is not 0, in fact there's no value at all.
>  > Second, given that nothing was changed between the two commands,
>  > it's strange that 'null_ptr' is mentioned in -var-update.
>  > 
>  > Before I go changing code, do everybody agree that:
>  > 
>  > 1. The output of -var-create should either have no "value"
>  > field at all, or value="", as is used in some other context.
>  > 2. The output of -var-update should not include anything.
>  > 
>  > Also, we probably should include in_scope="false" in output of
> 
>             probably should not include?
> 
>  > -var-create, but I'm not quite sure.
> 
> Are there any real situations where you would want to create a variable object
> of a constant?  If not, then, apart from ensuring that such objects don't crash
> GDB, I don't think this is an urgent issue.

That's testcase example. Replace **0 with "**some_pointer" and you have a real
use-case.

- Volodya