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[QUOTE="Alf P. Steinbach, post: 4403082"]
<code>
#include <memory>
using namespace std;

struct T {};

T* foo() { return new T; }
T const* bar() { return foo(); }

int main()
{
unique_ptr< T const >       p1( bar() );        // OK
unique_ptr< T const [] >    a1( bar() );        // OK

unique_ptr< T const >       p2( foo() );        // OK
unique_ptr< T const [] >    a2( foo() );        // ? this is line #15
}
</code>

Example errors with Visual C++ 10.0 and MinGW g++ 4.4.1:

foo.cpp
foo.cpp(15) : error C2248: 'std::unique_ptr<_Ty>::unique_ptr' : cannot
access private member declared in class 'std::uni
que_ptr<_Ty>'
with
[
_Ty=const T []
]
C:\Program Files (x86)\Microsoft Visual Studio
10.0\VC\INCLUDE\memory(2509) : see declaration of 'std::unique_pt
r<_Ty>::unique_ptr'
with
[
_Ty=const T []
]

[d:\dev\test]
c:\program files
(x86)\codeblocks\mingw\bin\../lib/gcc/mingw32/4.4.1/include/c++/bits/unique_ptr.h:
In function 'int mai
n()':
c:\program files
(x86)\codeblocks\mingw\bin\../lib/gcc/mingw32/4.4.1/include/c++/bits/unique_ptr.h:379:
error: deleted f

std::default_delete<const T []>]'
foo.cpp:15: error: used here

[d:\dev\test]
</example>

It seems to me that the array version should accept the same implicit
const-adding as the non-array version.

The difference is that the array version should not accept pointer to a
derived class, and that's the machinery that apparently kicks in above.

Is the code valid?

If the code is formally invalid, does the standard's wording reflect the
intent (i.e., is a DR appropriate)?

If no to the first and yes to the second, is the intent defective (i.e.,
again, is a DR appropriate)?

Cheers,

- Alf
[/QUOTE]

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