Undefined Reference to code from my libraries

[Laner107]

I know this has to do with the linking of the library with the compiler but I used x64 bit bash with Mingw64 to install and build the 64bit jsoncpp library using vpckg, I make sure to link the .lib file which is json.cpp inside the "installed" folder inside vpckg, i also include the include path, and then transfer the .dll of the library in the bin to my "release folder" within my program and link it with

win32: LIBS += -L$$PWD/../../Libraries/vcpkg/installed/x64-windows/lib/ -ljsoncpp
LIBS += C:/Users/laner/Desktop/AlgoApplication/AlgoAppV02/AlgoAppV02/release/jsoncpp.dll
INCLUDEPATH += $$PWD/../../Libraries/vcpkg/installed/x64-windows/include/json
DEPENDPATH += $$PWD/../../Libraries/vcpkg/installed/x64-windows/include/json

but still i get undefined reference.. here are pictures of the files and error messages, any help would be appreciated.

[jsulm]

@Laner107 There is no need to link twice to the same lib (especially not to the one in build/release folder).
The first LIBS should be enough.
Take a look at https://doc.qt.io/qt-5/qmake-variable-reference.html#libs
On Windows you link against *.lib not *.dll, so it should be:

win32: LIBS += -L$$PWD/../../Libraries/vcpkg/installed/x64-windows/lib/jsoncpp.lib
INCLUDEPATH += $$PWD/../../Libraries/vcpkg/installed/x64-windows/include/json

[Laner107]

@jsulm Thank you for the reply! I am now getting a bunch of undefined reference areas to my functions in my classes ie Json::value and Json::Reader? Any other fixes you have?

[jsulm]

@Laner107 said in Undefined Reference to code from my libraries:

Json::value and Json::Reader

Are those from the jsoncpp lib?

[Pablo J. Rogina]

@Laner107 just in case, are you sure you want to use an external library to deal with JSON data?

There's already JSON support in Qt.

[Laner107]

@jsulm I just want to verify this method of building libraries is compatiable with QT as libaries still confuse me, below is the steps i took.

1.) Run gitbash x64 mingw and clone and build vcpkg.
2.) Wtihin gitbash x64 mingw, install jsoncpp:x64-windows through vcpkg
3.) Include the jsoncpp.lib and json include path to qt.

So nothing else needs to be done for qt to essentially work?

[Laner107]

@jsulm Yes they are in the library
@Pablo-J-Rogina What is it called? And it can parse .json files?

[SGaist]

Hi,

AFAIK, vcpkg uses Visual Studio, are you sure these libraries where built using MinGW ?

As for Qt JSON support, @Pablo-J-Rogina already provided the link to the documentation of the module.

[Laner107]

@SGaist So is there a way to install and build using gitbash without using vcpkg? I figured it was the most easiest.