Re: [boost] [config] BOOST_NO_CXX11_HDR_CODECVT is not defined for VC14

Subject: Re: [boost] [config] BOOST_NO_CXX11_HDR_CODECVT is not defined for VC14
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2015-07-26 15:21:23

On Sun, Jul 26, 2015 at 10:02 PM, John Maddock
<jz.maddock_at_[hidden]> wrote:
>
>
> On 26/07/2015 16:33, Andrey Semashev wrote:
>>
>> Hi,
>>
>> I see that BOOST_NO_CXX11_HDR_CODECVT is not defined for MSVC-14, although
>> it is known that the codecvt facets are unusable because of linkin errors:
>>
>>
>> https://connect.microsoft.com/VisualStudio/feedback/details/1348277/link-error-when-using-std-codecvt-utf8-utf16-char16-t
>>
>> You can also see STL mentioning DevDiv#1060849 here:
>>
>>
>> http://blogs.msdn.com/b/vcblog/archive/2014/11/12/visual-studio-2015-preview-now-available.aspx?PageIndex=2
>>
>> and I can see that the problem is not fixed in RTM. This also concerns
>> std::codecvt specializations for char16_t and char32_t.
>>
>> Can we define the BOOST_NO_CXX11_HDR_CODECVT macro for MSVC?
>>
>
> Investigating.... looks like a regression from VC12?

It seems so. The following test fails to link with VC14 and succeeds
with VC10, 11 and 12.

#include <cstddef>
#include <locale>
#include <codecvt>
#include <iostream>

int main()
{
    std::locale loc;
    std::cout << "Has codecvt<char16_t>: " << std::has_facet<
std::codecvt< char16_t, char, std::mbstate_t > >(loc) << std::endl;
    std::cout << "Has codecvt<char32_t>: " << std::has_facet<
std::codecvt< char32_t, char, std::mbstate_t > >(loc) << std::endl;

    loc = std::locale(loc, new std::codecvt_utf8< wchar_t >());
    loc = std::locale(loc, new std::codecvt_utf8< char16_t >());
    loc = std::locale(loc, new std::codecvt_utf8< char32_t >());

    loc = std::locale(loc, new std::codecvt_utf16< wchar_t >());
    loc = std::locale(loc, new std::codecvt_utf16< char16_t >());
    loc = std::locale(loc, new std::codecvt_utf16< char32_t >());

    loc = std::locale(loc, new std::codecvt_utf8_utf16< wchar_t >());
    loc = std::locale(loc, new std::codecvt_utf8_utf16< char16_t >());
    loc = std::locale(loc, new std::codecvt_utf8_utf16< char32_t >());

    return 0;
}