[cfe-commits] r120872 - in /cfe/trunk: lib/Sema/SemaDeclAttr.cpp test/Sema/warn-unused-function.c

[Argyrios Kyrtzidis]

On Dec 6, 2010, at 10:12 AM, John McCall wrote:

> 
> On Dec 6, 2010, at 10:06 AM, Argyrios Kyrtzidis wrote:
> 
>> On Dec 5, 2010, at 8:33 PM, John McCall wrote:
>> 
>>> 
>>> On Dec 3, 2010, at 5:12 PM, Argyrios Kyrtzidis wrote:
>>> 
>>>> Author: akirtzidis
>>>> Date: Fri Dec  3 19:12:11 2010
>>>> New Revision: 120872
>>>> 
>>>> URL: http://llvm.org/viewvc/llvm-project?rev=120872&view=rev
>>>> Log:
>>>> Mark functions referenced by 'cleanup' attribute as used. Fixes rdar://8728293
>>> 
>>>> 
>>>> Modified:
>>>> cfe/trunk/lib/Sema/SemaDeclAttr.cpp
>>>> cfe/trunk/test/Sema/warn-unused-function.c
>>>> 
>>>> Modified: cfe/trunk/lib/Sema/SemaDeclAttr.cpp
>>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDeclAttr.cpp?rev=120872&r1=120871&r2=120872&view=diff
>>>> ==============================================================================
>>>> --- cfe/trunk/lib/Sema/SemaDeclAttr.cpp (original)
>>>> +++ cfe/trunk/lib/Sema/SemaDeclAttr.cpp Fri Dec  3 19:12:11 2010
>>>> @@ -1450,6 +1450,7 @@
>>>> }
>>>> 
>>>> d->addAttr(::new (S.Context) CleanupAttr(Attr.getLoc(), S.Context, FD));
>>>> +  FD->setUsed();
>>>> }
>>> 
>>> Technically, you can use __attribute__((cleanup)) inside a template.  This should use MarkDeclarationReferenced, and then there should be special instantiation logic for the attribute.
>> 
>> Hmm, is this really the right approach ? If it's referenced from a template which is not instantiated, it's not used from the codegen perspective but how about from the user's perspective:
>> 
>> -We emit a warning that the function 'foo' is unused.
>> -User removes function 'foo'
>> -Now we emit an error that 'foo' is not found.
> 
> Oh, you mean if a function is referenced from a template definition that's never instantiated?  Yeah, that's a valid user complaint.  That's not specific to attribute((cleanup)), though;  any reference without dependent ADL will have that issue.

For this specific case, the lookup is always non-dependent, I think the right user perspective is that the 'foo' is referenced if the attribute references it even in uninstantiated templates.

> 
> John.