boost lib error

[Bharth]

Hi guys......
please help how to slove this problem
after adding boost libraries im getting these errors...........................

error: undefined reference to `boost::system::detail::system_category_ncx()'
error:undefined reference to `boost::system::detail::generic_category_ncx()'
collect2.exe:-1: error: error: ld returned 1 exit status

this is header file error_code.hpp here im getting error

inline const error_category & system_category() BOOST_SYSTEM_NOEXCEPT
{
    return detail::system_category_ncx();
}

inline const error_category & generic_category() BOOST_SYSTEM_NOEXCEPT
{
    return detail::generic_category_ncx();
}

[VRonin]

Boost system is not header-only. You need to build boost and link it to your app (LIBS += in qmake/QtCreator)

[Bharth]

i added this is .pro file

INCLUDEPATH += $$PWD/../../external/include
DEPENDPATH += $$PWD/../../external/lib/boost

CONFIG(release, debug|release): LIBS += -L$$PWD/../../external/lib/boost -lboost_random-x32
else:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../external/lib/boost -lboost_random-x32-gd

CONFIG(release, debug|release): LIBS += -L$$PWD/../../external/lib/boost -lboost_system-x32
else:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../external/lib/boost -lboost_system-x32-gd

CONFIG(release, debug|release): LIBS += -L$$PWD/../../external/lib/boost -lboost_date_time-x32
else:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../external/lib/boost -lboost_date_time-x32-gd

[jiancaiyang]

Boost::system could be built statically using its source code, I think it is better than linking libraries.

[Dimple]

hello bharth,,,,
follow these steps bcz it doesnt work with lib files so alrdy u hv built boost libraries so rebuild it as below,,
1.download boost
2.build boost in command prompt (else install developer command prompt)
3.while building u should add these paths,,
drive name (ex. D: then click on enter)
cd enter path where ur boost has downloaded(ex. cd D:\boost_1_68_0) click on enter & add
bootstrap.bat again click on enter wait until it completes itz building after that add this path
b2 toolset=gcc (it takes some time to build if u find any error after adding this ,,,error like command not recognised gc++...etc then install mingw then it works fine )
after building u get .a files do copy paste into ur lib folder .

[Bharth]

ok thank you dimple

[Bharth]

although getting same errors want me to change path names??

[Ratzz]

@Bharth
I Prefer building boost using CMake GUI using suitable compiler.
Steps: https://svn.boost.org/trac10/wiki/CMakeConfigAndBuild#ConfiguretheBoostsourcetree

What compile do you use? What are the binaries you use build with ? What is the build configuration of those libraries?

[Dimple]

INCLUDEPATH += $$PWD/../../external/include
win32: DEPENDPATH += $$PWD/../../external/lib/boost/win32/
else:unix: DEPENDPATH += $$PWD/../../external/lib/boost/mac/

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../external/lib/boost/win32 -lboost_random-mgw63-x32
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../external/lib/boost/win32 -lboost_random-mgw63-d-x32
else:unix: LIBS += -L$$PWD/../../external/lib/boost/mac -lboost_random

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../external/lib/boost/win32 -lboost_system-mgw63-x32
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../external/lib/boost/win32 -lboost_system-mgw63-d-x32
else:unix: LIBS += -L$$PWD/../../external/lib/boost/mac -lboost_system

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../external/lib/boost/win32 -lboost_date_time-mgw63-x32
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../external/lib/boost/win32 -lboost_date_time-mgw63-d-x32
else:unix: LIBS += -L$$PWD/../../external/lib/boost/mac -lboost_date_time

win32: LIBS += -lws2_32

bharth change path name & add last line into pro.file

[Bharth]

ya thank you errors cleared.....

[Dimple]

welcome #bharth