Re: Declaring the same DS in caller and callee

[Vern Hamberg <vhamberg@xxxxxxxxxxx>]

Simon

Glad to hear I'm not crazy - I don't have the problem now - I solved it 
long ago - just did not remember what triggered it anymore.

Was responding to someone who simply listed one of these without 
speaking of setting the pointer to something real.

;-)

Back to pretending I'm working.

Vern

Simon Coulter wrote:
> On 17/02/2009, at 4:58 AM, Vern Hamberg wrote:
>
>   
> > I don't remember the circumstances, and it may have been in an earlier
> > release - I have run into the need to declare the pointer and/or to
> > initialize the pointer explicitly with the %addr() function. The  
> > syntax
> > you give below seems to work most of the time, however. As I say, I
> > don't remember where I've had the problem. But leaving out one or both
> > items resulted in an MCH3601.
> >     
>
>
> You might want to rethink this. Both
>
> D var		S		10	BASED(@var)
>
> and
>
> D @var		S		  *
> D var		S		10	BASED(@var)
>
> will result in a NULL pointer named @var being declared and var will  
> be based on that NULL pointer. If your code attempts to reference  
> either the pointer or the based storage you will get MCH3601 (except  
> for the obvious case of a reference that assigns an address to the  
> pointer).
>
> You must set the basing pointer to a valid address before referencing  
> the based variable. Whether you do that by using INZ(%ADDR())--which  
> obviously requires you to explicitly declare the basing pointer--or  
> via an EVAL @var = %ADDR() operation is immaterial. This is true of  
> all languages with pointer support (on iSeries). If the pointer is  
> not set you will get MCH3601 when you attempt to reference storage  
> based on that pointer.
>
> Perhaps you were bitten by Barbara's earlier point that a global  
> basing pointer will be overridden by a compiler-generated local  
> basing pointer? If so, that's a different issue.
>
> Regards,
> Simon Coulter.
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