Boost.Test VC memory leak report should direct to stderr

[anonymous]

Boost.Test includes a memory leak detection feature (uses the ones MSV provided). Unfortunately it redirects the output to stdout, not conventional stderr.

We are currently creating XML-based test reports. If the memory leak happended, the XML becomes ill-formed. For better interoperability, the debug output should go to stderr.

I traced the place where the called in placed (in boost/test/impl/debug.ipp)

#ifdef BOOST_MS_CRT_BASED_DEBUG
    int flags = _CrtSetDbgFlag( _CRTDBG_REPORT_FLAG );

    if( !on_off )
        flags &= ~_CRTDBG_LEAK_CHECK_DF;
    else  {
        flags |= _CRTDBG_LEAK_CHECK_DF;
        _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
        _CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDOUT);
    }

    _CrtSetDbgFlag ( flags );
#endif // BOOST_MS_CRT_BASED_DEBUG

The call _CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDOUT); should be changed to

_CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDERR);

[Gennadiy Rozental]

(In [75038]) use stderr as default stream for reporting leak errors (the same as any other reports) Fixes #5036