Re: [gfortran,patch] Fix wrong-code for ASSOCIATED

[Brooks Moses <bmoses at stanford dot edu>]

Steve Kargl wrote:
> Arguments.
>   POINTER    shall be a pointer and may be of any type.
>              Its pointer association status shall not be undefined.
>
> With the program the FX posted, gfortran needs to issue an
> error and exit.

Does it?  I agree that it would be nice if it did, but I don't think it 
"needs to" diagnose this error -- this text you quote isn't a compiler 
constraint.  The situation is exactly akin to referencing a variable 
with an undefined value, and we don't diagnose that in the general case. 
 I don't think this _can_ always be diagnosed in the general case.

We could possibly do something like automatically initializing all 
pointers to a value that means "undefined", but even that's tricky when 
they're deep in an array of derived types as in the given case.  Any 
solution to that one ought, in my opinion, be written generally enough 
to handle initializing variable values to an "undefined" sentinel value 
as well.

- Brooks