[Interest] MSVC 2013 Bug?

[Thiago Macieira]

On Thursday 12 November 2015 23:56:20 Igor Mironchik wrote:
> > First of all, allocating memory when throwing exceptions is bad practice.
> > Avoid it by redesigning your code.
> 
> Can you, please, explain why allocating memory when throwing exception
> is bad practice? Or just can you give a link on any article about this
> question.... Thank you.

Because allocating memory in response to an OOM situation is stupid, so 
std::exception doesn't require it; instead, it uses a pointer that is expected 
to be valid forever. The exception mechanism uses a pre-allocated buffer so 
that exceptions can still work in an OOM condition.

> > Because toLocal8Bit() returns a QByteArray and QByteArray has an operator
> > const char*(). Why would it not be possible?
> > 
> > Do note that it compiles, but it's probably incorrect because
> > std::runtime_error will probably be carrying a dangling pointer.
> > 
> > Like I said, you should redesign so you don't allocate memory when
> > throwing
> > exceptions.
> 
> Thank you, I understood. Just interesting why Qt 5.5.1 on Windows
> compiled without QT_NO_CAST_FROM_BYTEARRAY and on Linux with this one?

It isn't. Your test is faulty. The only piece of code that turns that macro on 
is moc's own build.

-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center