Re: [boost] [config] vc10 and BOOST_NO_DECLTYPE

Subject: Re: [boost] [config] vc10 and BOOST_NO_DECLTYPE
From: Anthony Williams (anthony.ajw_at_[hidden])
Date: 2010-04-21 03:25:26

Eric Niebler <eric_at_[hidden]> writes:

> John Maddock wrote:
>> Beman Dawes wrote:
>>> Eric Niebler wrote:
>>>> What that means for Boost.Config is unclear to me. We may decide
>>>> to define a defect macro for this particular buggy decltype
>>>> behavior, since gcc's decltytpe works this way, too.
>>> 
>>> That sounds like a reasonable approach. Care to propose a name?
>>> What is the CWG issue number?
>> 
>> If all compilers decltype implementations have this issue, *and* it
>> is currently std conforming, then maybe we shouldn't have a defect
>> macro at all?  Or at least wait until we know whether this is likely
>> to be fixed in the std?
>> 
>> Just my 2c, John.
>
> Oh. Yeah, that sounds better. And it seems to me that VC10's decltype
> probably works well enough to leave BOOST_NO_DECLTYPE undefined, but I'd
> see some more examples of code in the wild that would be broken by the
> bug Anthony is referring to.

I found the bug when trying to use a decltype-based result_of on a
function returning a class with a user-defined default constructor. I'll
try and find some other examples.

Anthony
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