[cfe-commits] r53964 - /cfe/trunk/lib/Analysis/CheckDeadStores.cpp

[Chris Lattner]

On Jul 23, 2008, at 9:10 PM, Ted Kremenek wrote:

>
> On Jul 23, 2008, at 5:24 PM, Chris Lattner wrote:
>
>>
>> On Jul 23, 2008, at 3:19 PM, Ted Kremenek wrote:
>>
>>> Author: kremenek
>>> Date: Wed Jul 23 17:19:56 2008
>>> New Revision: 53964
>>>
>>> URL: http://llvm.org/viewvc/llvm-project?rev=53964&view=rev
>>> Log:
>>> Don't flag dead stores when the result of a preincrement/ 
>>> predecrement is used in an enclosing expression.
>>
>> So you don't warn about "print(++x)" if x is dead after that?  Why  
>> not warn "consider changing ++x to 'x+1'"?
>
> My reasoning was to reduce noise.  Stylistically many people like to  
> do ++x to compute the value used in the enclosing expression, and  
> I'm a little doubtful that warning about these kinds of dead stores  
> will ever find real errors.  Thoughts?

If the incremented version of x is dead, I'd suggest reporting it, but  
as a different class of issue than normal dead variable.  That way  
people could filter out all the reports (with the check box) if their  
coding style depends on this sort of thing.  What do you think?

Increasingly, I think that this is a great way to deal with classes of  
false positives that arise do to "weird" coding conventions.

-Chris