undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev in Qt?

Vivek_A

hello iam solved my linking error of mongodb with qt creator , now i can include header file but when in command mongocxx::instance inst; error came

E:/vivek/dw_tdoa_controller5/dw_tdoa_controller/main.cpp:37: undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev'

my pro file

win32:CONFIG(release, debug|release): LIBS += -LC:/mongo-cxx-driver/lib/ -llibmongocxx.dll
else:win32:CONFIG(debug, debug|release): LIBS += -LC:/mongo-cxx-driver/lib/ -llibmongocxx.dll

INCLUDEPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi
DEPENDPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi

win32:CONFIG(release, debug|release): LIBS += -LC:/mongo-cxx-driver/lib/ -llibbsoncxx.dll
else:win32:CONFIG(debug, debug|release): LIBS += -LC:/mongo-cxx-driver/lib/ -llibbsoncxx.dll

INCLUDEPATH += C:/mongo-cxx-driver/include/bsoncxx/v_noabi
DEPENDPATH += C:/mongo-cxx-driver/include/bsoncxx/v_noabi

how to fix it

Vivek_A

my compiler is mingw32bit and mongocxx driver build in 64 bit . so thats make problem , i solved it by installing 64bit Qt.

jsulm

@Vivek_A Please take a look at https://doc.qt.io/qt-5/qmake-variable-reference.html#libs
and fix your LIBS (hint: you need to add .lib not .dll).

Vivek_A

@jsulm hi, its build using mingw64 so there is only .a file not .lib .
full file is llibmongocxx.dll.a , this pro file command is generate by this IDE not manually written .

jsulm

@Vivek_A Please take a look at the link I gave you and compare with what you did...
Should be

LIBS += C:/mongo-cxx-driver/lib/llibbsoncxx.dll

Vivek_A

@jsulm

LIBS += C:/mongo-cxx-driver/lib/llibbsoncxx.dll

INCLUDEPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi
DEPENDPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi

Output:

g++: error: C:\mongo-cxx-driver\lib\llibbsoncxx.dll: No such file or directory
Makefile.Release:233: recipe for target 'release\RTLSController.exe' failed

jsulm

@Vivek_A said in undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev in Qt?:

C:\mongo-cxx-driver\lib\llibbsoncxx.dll

So, does this file exist? And I mean exact this path.

JonB

@Vivek_A said in undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev in Qt?:

g++: error: C:\mongo-cxx-driver\lib\llibbsoncxx.dll: No such file or directory

Originally you had -llibbsoncxx.dll. I am thinking the leading -l was an argument to the linker, followed by the DLL file name? Which would make it LIBS += C:/mongo-cxx-driver/lib/libbsoncxx.dll (only one l)?

However, this is a separate matter from whether you should be specifying a .dll here, I thought you would need either a .lib (MSVC) or a .a (MinGW)...?

jsulm

@JonB I wanted the OP to find that out :-) This is something a developer should do first before asking in a forum. Really basic stuff.

JonB

@jsulm
Whoops, sorry for treading on your toes!

However I have amended my answer above since you saw it. Is one supposed to specify any DLL file in LIBS += ...?

jsulm

@JonB It should be .lib, yes. But OP claims there is no .lib file, but I'm not a Windows developer.

JonB

@jsulm
A .lib will not do him, as he is using MinGW/gcc. I now see he wrote earlier:

full file is llibmongocxx.dll.a

That is an unusual naming convention! If that is really the case, and applies to llibbsoncxx.dll.a too, then it would indeed seem to be as he wrote. But the error message

g++: error: C:\mongo-cxx-driver\lib\llibbsoncxx.dll: No such file or directory

shows what MinGW seems actually to be looking for, no mention of a .a suffix. So I'm not sure what is going on....

Vivek_A

@jsulm ok, i understand idid this

LIBS += C:/mongo-cxx-driver/lib/libbsoncxx.dll.a

INCLUDEPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi
DEPENDPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi

included but error that said first remains

./release\main.o:main.cpp:(.text+0x1d): undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev'
./release\main.o:main.cpp:(.text+0xee): undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceD1Ev'
./release\main.o:main.cpp:(.text+0x14e): undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceD1Ev'

if you dont know about windows side of this , then its ok.
@JonB i have doubt , the compiler is mingw 32 and i build the mongdb in mingw 64 is this makes any issues

jsulm

@Vivek_A You need to link at least one more lib containing the missing symbols (libmongocxx I guess).

JonB

@Vivek_A said in undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev in Qt?:

LIBS += C:/mongo-cxx-driver/lib/libbsoncxx.dll.a

This looks much more reasonable than before!

Now as @jsulm says it looks like you need some further similars for other library files required to link successfully.

@JonB i have doubt , the compiler is mingw 32 and i build the mongdb in mingw 64 is this makes any issues

I am not sure what you are saying. It will not be possible to mix 64-bit-compiled code with 32-bit-compiled code in one executable. The compiler's bit-ness is not at issue, rather only whichever bit-ness it is generating code for.

Start by trying what @jsulm has pointed out, then deal with bit-ness if there is still an error.....

Vivek_A

@JonB modified

LIBS += C:/mongo-cxx-driver/lib/libbsoncxx.dll.a
LIBS += C:/mongo-cxx-driver/lib/libmongocxx.dll.a
INCLUDEPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi
DEPENDPATH += C:/mongo-cxx-driver/include/mongocxx/v_noabi

INCLUDEPATH += C:/mongo-cxx-driver/include/bsoncxx/v_noabi
DEPENDPATH += C:/mongo-cxx-driver/include/bsoncxx/v_noabi

clean & rebuilded
Output:

./release\main.o:main.cpp:(.text+0x19): undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev'
./release\main.o:main.cpp:(.text+0x23): undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceD1Ev'
collect2.exe: error: ld returned 1 exit status

Vivek_A

@Vivek_A anybody help...is that compiler problem

./debug\main.o: In function `Z5qMainiPPc':
E:/vivek/dw_tdoa_controller7/dw_tdoa_controller/main.cpp:36: undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev'
E:/vivek/dw_tdoa_controller7/dw_tdoa_controller/main.cpp:36: undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceD1Ev'
E:/vivek/dw_tdoa_controller7/dw_tdoa_controller/main.cpp:36: undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceD1Ev'
collect2.exe: error: ld returned 1 exit status


Makefile:36: recipe for target 'debug' failed
mingw32-make[1]: *** [debug\RTLSController.exe] Error 1
mingw32-make: *** [debug] Error 2
17:25:51: The process "C:\Qt\Qt5.11.2\Tools\mingw530_32\bin\mingw32-make.exe" exited with code 2.
Error while building/deploying project dw_controller (kit: Desktop Qt 5.11.2 MinGW 32bit)
When executing step "Make"

SGaist

Try inverting the order of the libraries you are linking.

Vivek_A

@SGaist tried , still same error , i think its not in the linking of lib, may be the installation or compiler problem... what u think???

mrjj

@Vivek_A

Hi
I saw this line
building/deploying project dw_controller (kit: Desktop Qt 5.11.2 MinGW 32bit)

but you said " its build using mingw64 "

So are your 32 bit app trying to load 64 bit DLL ?

Vivek_A

@mrjj hi sir, i build and installed mongocxx driver using ming64. The app running in Qt is Desktop Qt 5.11.2 MinGW 32bit, ie a mingw 32 bit compiler

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Solved undefined reference to `_imp___ZN8mongocxx7v_noabi8instanceC1Ev in Qt?