So it turns out that Qt libraries are dynamically linked with the C++
runtime.
Also, you said that libbitcoin should be built with static C++ runtime
linking.
Mixing is not a good idea, as you and others have said, so I tried to
rebuild libbitcoin now
with dynamic linking, by going in MSVC to
Solution Explorer->Properties->Configuration Properties->C/C++->Code
Generation->Runtime Library
and choosing Multi-threaded Debug DLL (/MDd).
This rebuilding works, and I am able to now link my Qt project to
libbitcoin while actually using some basic libbitcoin functions.
My question is, is this safe? Also, what about other dependencies which
libbitcoin has, I assume the link settings in the MSVC libbitcoin project
do not propagate to these? If so,why do you think rebuilding libbitcoin
worked?
Also, when I try to use more complicated libbitcoin features (right now Im
just using data_chunk and decode_base16) which involve transactions and
signing, then the linker cannot find secp2561 library:
libbitcoin.lib(ec_keys.obj) : error LNK2019: unresolved external symbol
secp256k1_stop referenced in function "public: __cdecl
libbitcoin::init_singleton::~init_singleton(void)"
(??1init_singleton@libbitcoin@@QEAA@XZ)
Shouldnt that be statically linked into libbitcoin?
best
Bedeho
On 24 March 2015 at 11:09, Bedeho Mender <bedeho.mender@???> wrote:
> Fantastic, that worked!
>
> I am now able to build a project which includes libbitcoin headers!
>
> I get a bunch of issues with linking when I actually try to use libbitcoin
> functions, but I think I may be able to resolve those.
>
> Thanks a lot Eric!
>
> On 24 March 2015 at 10:17, Eric Voskuil <eric@???> wrote:
>
>> This isn't a problem with cross-compiler linking (or a regression), it's
>> simply the result of the fact that we don't yet have the exports/imports
>> properly/fully defined for DLL linkage (not yet supported).
>>
>> The errors are the result of BC_API getting defined to
>> __declspec(dllimport). You just need to define BC_STATIC. See define.hpp.
>>
>> e
>>
>> On 03/24/2015 01:16 AM, Eric Voskuil wrote:
>> > Hi Bedeho,
>> >
>> > I suspect the errors are the result of a change I made today in master.
>> > I'll look into it.
>> >
>> > The define warning pertains to your project. All libbitcoin VS. projects
>> > declare Windows XP SP2 as the build target:
>> >
>> > _WIN32_WINNT=0x0600
>> >
>> > If you currently have no reason to do otherwise I'd recommend you do the
>> > same in your project.
>> >
>> > e
>> >
>> > On 03/24/2015 12:01 AM, Bedeho Mender wrote:
>> >> Hi Eric,
>> >>
>> >> Giving the new headers a try.
>> >>
>> >> As before, built libbitcoin with MSVC Nov 2013 CTP, and then I have an
>> >> example Qt project which uses the vanilla MSVC2013.
>> >>
>> >> I get different build errors this time, and fewer of them. As one would
>> >> expect, nothing related to constexpr.
>> >>
>> >> There are basically headers which cause problems, as seen by these
>> errors
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(74) :
>> >> error C2375: 'libbitcoin::operator >' : redefinition; different linkage
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(57) :
>> >> see declaration of 'libbitcoin::operator >'
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(76) :
>> >> error C2375: 'libbitcoin::operator <=' : redefinition; different
>> linkage
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(59) :
>> >> see declaration of 'libbitcoin::operator <='
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(78) :
>> >> error C2375: 'libbitcoin::operator <<' : redefinition; different
>> linkage
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(61) :
>> >> see declaration of 'libbitcoin::operator <<'
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(80) :
>> >> error C2375: 'libbitcoin::operator /' : redefinition; different linkage
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(63) :
>> >> see declaration of 'libbitcoin::operator /'
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(82) :
>> >> error C2375: 'libbitcoin::operator +' : redefinition; different linkage
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(65) :
>> >> see declaration of 'libbitcoin::operator +'
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(84) :
>> >> error C2375: 'libbitcoin::operator ==' : redefinition; different
>> linkage
>> >>
>> >>
>> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/math/hash_number.hpp(67) :
>> >> see declaration of 'libbitcoin::operator =='
>> >>
>> >> Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately. For
>> example:
>> >>
>> >> - add -D_WIN32_WINNT=0x0501 to the compiler command line; or
>> >>
>> >> - add _WIN32_WINNT=0x0501 to your project's Preprocessor Definitions.
>> >>
>> >> Assuming _WIN32_WINNT=0x0501 (i.e. Windows XP target).
>> >>
>> >> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/utility/binary.hpp(79)
>> >> : error C2375: 'libbitcoin::operator ==' : redefinition; different
>> linkage
>> >>
>> >> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/utility/binary.hpp(64)
>> >> : see declaration of 'libbitcoin::operator =='
>> >>
>> >> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/utility/binary.hpp(84)
>> >> : error C2375: 'libbitcoin::operator >>' : redefinition; different
>> linkage
>> >>
>> >> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/utility/binary.hpp(66)
>> >> : see declaration of 'libbitcoin::operator >>'
>> >>
>> >> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/utility/binary.hpp(86)
>> >> : error C2375: 'libbitcoin::operator <<' : redefinition; different
>> linkage
>> >>
>> >> C:\libbitcoin\libbitcoin\include\bitcoin/bitcoin/utility/binary.hpp(68)
>> >> : see declaration of 'libbitcoin::operator <<'
>> >>
>> >> This is what I'm working with: https://github.com/bedeho/QtLibbitcoin
>> >>
>> >> best
>> >> Bedeho
>> >>
>> >>
>> >> On 23 March 2015 at 22:07, Eric Voskuil <eric@???
>> >> <mailto:eric@voskuil.org>> wrote:
>> >>
>> >> Regarding the /Zc:threadSafeInit option, this was added later, in
>> the
>> >> June "VS14" CTP (now VS2015 in CTP 6), so I'm leaving it as-is.
>> >>
>> >> e
>> >>
>> >>
>> >> On 03/23/2015 01:49 PM, Eric Voskuil wrote:
>> >> > I've updated all libbitcoin repos so that there is no code in
>> >> published
>> >> > headers requiring the VC++ CTP compiler (generally C++11 stuff,
>> mostly
>> >> > constexpr).
>> >> >
>> >> > I've done the same in all test projects, which I've also changed
>> >> to not
>> >> > use the CTP compiler and instead use VC++12. This provides a
>> >> convenient
>> >> > means to ensure that the CTP requirement doesn't creep into the
>> >> headers
>> >> > or break in another manner. It also provides an example of how
>> to link
>> >> > to the main libraries (built with the CTP compiler) using the RTM
>> >> compiler.
>> >> >
>> >> > There is a small additional runtime library that augments the
>> CRT when
>> >> > linking with VC12. This is automatically incorporated, although
>> I may
>> >> > try and get rid of that requirement by using "
>> /Zc:threadSafeInit" as
>> >> > described here:
>> >> >
>> >> >
>> >>
>> http://blogs.msdn.com/b/vcblog/archive/2014/06/03/visual-studio-14-ctp.aspx
>> >> >
>> >> > The changes are accomplished using three new libbitcoin macros
>> >> > (BC_CONSTREXPR, BC_CONSTFUNC and BC_NOEXCEPT) so that non-MSVC
>> builds
>> >> > are unaffected. These should be used in all published headers and
>> >> tests.
>> >> >
>> >> > e
>> >> >
>> >> > On 03/19/2015 02:39 PM, Eric Voskuil wrote:
>> >> >> It may not be too difficult to remove from headers. Templates
>> may
>> >> >> present problems beyond the use of constexpr. I'd be happy to
>> >> review a
>> >> >> pull request.
>> >> >>
>> >> >> e
>> >> >>
>> >> >> On 03/19/2015 02:07 PM, Bedeho Mender wrote:
>> >> >>> 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@???
>> >> <mailto:eric@voskuil.org>
>> >> >>> <mailto:eric@voskuil.org <mailto:eric@voskuil.org>>> 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>
>> >> >>> <mailto:eric@voskuil.org <mailto:eric@voskuil.org>>
>> >> >>> > <mailto:eric@voskuil.org <mailto:eric@voskuil.org>
>> >> <mailto:eric@voskuil.org <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> <mailto:bedeho.mender@gmail.com
>> >> <mailto:bedeho.mender@gmail.com>>
>> >> >>> <mailto:bedeho.mender@gmail.com
>> >> <mailto:bedeho.mender@gmail.com> <mailto:bedeho.mender@gmail.com
>> >> <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
>> >> >>>
>> >> >>>
>> >> >>
>> >> >
>> >>
>> >>
>> >> _______________________________________________
>> >> Libbitcoin mailing list
>> >> Libbitcoin@??? <mailto:Libbitcoin@lists.dyne.org>
>> >> https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/libbitcoin
>> >>
>> >>
>> >
>>
>>
>
::
Re: [Libbitcoin] Libbitcoin and Qt
