Re: [boost] Boost with Clang via MinGW-w64

Subject: Re: [boost] Boost with Clang via MinGW-w64
From: Beman Dawes (bdawes_at_[hidden])
Date: 2011-07-17 13:47:13

On Sun, Jul 17, 2011 at 11:07 AM, Joshua Boyce
<raptorfactor_at_[hidden]> wrote:
> According to the Clang mailing list this is in fact a Boost defect.
>
> http://lists.cs.uiuc.edu/pipermail/cfe-dev/2011-July/016195.html

Although the rest of that post seems correct, the paragraph mentioned
in that posting is wrong, since it is about copy assignment rather
than copy construction.

The correct paragraph in the FDIS is 18.2, paragraph 7, which reads
"If the class definition does not explicitly declare a copy
constructor, one is declared implicitly. If the class definition
declares a move constructor or move assignment operator, the
implicitly declared copy constructor is defined as deleted; otherwise,
it is defined as defaulted (8.4). The latter case is deprecated if the
class has a user-declared copy assignment operator or a user-declared
destructor. ..."

So this does look like a bug in Boost shared_ptr code.

Incidentally, I was recently bitten by the same problem, but
mistakenly thought I was dealing with a compiler bug so just worked
around it by defining the copy constructor:-)

--Beman