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To: gcc@gcc.gnu.org
From: David Brown <david.brown@hesbynett.no>
Subject: Re: Add uninitialized attribute?
Date: Sat, 21 Aug 2010 15:23:00 -0000
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Mark Mitchell wrote:
> Bernd Schmidt wrote:
> 
>>>> int x __attribute__ ((uninitialized));
>>>>
>>>> to tell compiler that it is OK for "x" to be uninitialized?
>> Better to call it "initialized", analogous to attribute used/unused.
> 
> I agree.
> 
>>> I think the general idea is reasonable.  I also think it might be worth
>>> spending a few minutes thinking about whether we can implement some more
>>> general diagnostic suppression mechanism.  E.g.,
>>>    int x __attribute__ ((ignore ("-Wuninitialized")));
>> Or this.
> 
> FWIW, I think that's overly ambitious.
> 

There is already an "optimise" function __attribute__ and matching 
#pragma's that temporarily change the optimisation flags for a function 
(and a similar set for target flags).  For warning messages, there are 
#pragma's (though no push/pop pragma, AFAIK).  Would it be practical to 
have a "diagnostic" function __attribute__ in the same style?  Then at 
least it would be possible to declare 
__attribute__((diagnostic("-Wno-uninitialized"))) on the function in 
question.