Hi Eric,

Ive been talking to some Qt developers, and it appears that you do indeed
have to rebuild Qt with a newer MSVC version, however, it turns out that
this is likely not possible with the present build system on Windows with
these new versions of MSVC (for reasons was not given).

How difficult would it be to have a version of libbitcoin where the CTP
2013 features were taken out, so that libbitcoin could be used with the
latest full release of MSVC 2013? That is, how prevalent is the usage of
C++11 features which only are implemented in the CTP? e.g. constexpr.

I would be happy to sponsor this dev work depending on how involved it
would be, and that would allow people to use libbitcoin with Qt - which I
think a lot of people will likely want to do, given that Qt is the most
popular C++ framework out there.

best
bedeho



On 17 March 2015 at 20:52, Eric Voskuil <eric@???> wrote:

> Ah yes, that's unfortunate. Now I remember I looked at QT a while back
> and determined I would need to compile QT to make it work. I decided to
> wait for time to resolve the issue :/
>
> e
>
> On 03/17/2015 06:27 AM, Bedeho Mender wrote:
> > Hi Eric, thanks for the quick response!
> >
> > It doesn't appear so to me, but perhaps I am misunderstanding the
> problem.
> >
> > When I make a minimal Qt project
> > (https://github.com/bedeho/QtLibbitcoin/blob/master/main.cpp) which uses
> > MSVC2013, then if I just
> > include the libbitcoin header #include <bitcoin/bitcoin.hpp>, then I get
> > lots of compile errors.
> >
> > The errors seem to be associated with certain c++11 features which
> > msvc2013 does
> > not support fully. Here is the first error I get
> >
> > C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash.hpp(31) :
> > error C2146: syntax error : missing ';' before identifier 'size_t'
> >
> > Which references line 31 in hash.hpp:
> >
> > constexpr size_t short_hash_size = 20;
> >
> > In this case, the problem seems to be that constexpr is a new feature
> > which msvc2013 does not support, from what I could understand by
> > reading up, and that CTP_Nov2013 was required for this reason. For
> > example, the release notes on this CTP explicitly mentions constexpr
> > support (http://www.microsoft.com/en-us/download/details.aspx?id=41151):
> > "constexpr (except for constructors)"
> >
> > Am I on the wrong track here? If not, getting Qt to work with CTP
> > is necessary to for using Libbitcon with Qt.
> >
> > bedeho
> >
> >
> > On 16 March 2015 at 22:48, Eric Voskuil <eric@???
> > <mailto:eric@voskuil.org>> wrote:
> >

> >     You can link to the libbitcoin VC++ libs using the basic v120
> >     compiler, they are compatible.

> >

> >     e

> >
> >

> >     > On Mar 16, 2015, at 8:58 AM, Bedeho Mender
> >     <bedeho.mender@??? <mailto:bedeho.mender@gmail.com>> wrote:
> >     >
> >     > I have built libbitcoin with msvc using the compiler Microsoft
> >     Visual C++ Compiler Nov 2013 CTP.

> >     >
> >     > I am trying to use libbitcoin with a Qt project running in
> >     QtCreator, however it seems this is not easy to do, that is get Qt
> >     to get with the CTP.

> >     >
> >     > Does anyone have any advice on this?

> >     >
> >     > best
> >     >  Bedeho

>
>