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Re: Formatting of function pointer value


Daniel Jacobowitz wrote:

> On Fri, Jul 08, 2005 at 12:00:44PM +0400, Vladimir Prus wrote:
>> 
>> Hello,
>> consider the following snippet:
>> 
>>     B* p2 = (B*)0x12345678;
>>     int (*p3)(int) = (fp)0x000000AE;
>> 
>> the value of p2 is printed like this:
>> 
>>    (gdb)info local
>>    ....
>>    p2 = (B *) 0xb8000540
>> 
>> 
>> the value of *p3 is printed like this:
>> 
>>    (gdb) print *p3
>>    $1 = {int (int)} 0xb7ee6e9c <__DTOR_END__+4>
>> 
>> I have a couple of questions:
>> 
>> 1. Why in both cases the type of value is printed? There's already
>> 'whatis' command. I've checked that code and it's printed
>> unconditionally. As the result, a GDB frontend must strip the type.
> 
> It is a feature, not a bug.  Why is your frontend using the
> command-line interface?  

Well, the debugger part in KDevelop was not written by me, so I don't know
why command-line interface, and not MI is used.

> DON'T do that!  Use MI nowadays, please please 
> please.

I'm sorry, but section 24 of gdb manual does not say why MI is better. Can
you give the reasons?

> The type is included because "print p2; $1 = 0x12345678" is very
> uninformative; that's how we print integers, not pointers.

I suppose that if I do "print p2" I have some idea what type of 'p2' is; I
don't print program variables at random. 

- Volodya



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