Qt and dlib in ubuntu linking problem

[SGaist]

Yes, a debug build contains all the debug symbols, has usually less optimisations, might assert if certains conditions are not met, might log what happens etc.

[Jimmy32]

@SGaist Thank you for your help but after build the Qt project as release to fit my dlib build i got another problem.
If there is no dlib deep learning network defined in my code, i can build but once i add a dlib network, i got a building error

 /home/jimmy/Desktop/Connected_Robotics_Watson/workco/work/mainWindow.cpp:-1: error: undefined reference to `dlib::cpu::pooling::pooling()'

i am lost... because in a normal cpp code compile with cmake, everything worked well.

Thanks,

[jsulm]

@Jimmy32 You're not linking dlib.
Try with LIBS/INCLUDEPATH in pro file instead of PKGCONFIG. See http://doc.qt.io/qt-5/qmake-variable-reference.html

[Jimmy32]

@jsulm Thank you
i have tried this before, i added the lib in the LIBS -ldlib but i got another error

:-1: error: /usr/local/lib/libdlib.a(cpu_dlib.cpp.o): undefined reference to symbol 'cblas_sscal'

...

[jsulm]

@Jimmy32 Can you show your pro file?
Does the dlib depend on other libraries (you can check with ldd)?

[Jimmy32]

@jsulm my .pro file:

QT += network
QT += widgets
TEMPLATE = app
TARGET = Connected


INCLUDEPATH += /usr/local/include
LIBS += -L /usr/local/lib -lopencv_core -lopencv_imgproc -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -ldlib
QMAKE_CXXFLAGS += -std=c++11
# PKGCONFIG = dlib-1


# Input
HEADERS += mainWindow.hpp
SOURCES += main.cpp mainWindow.cpp

and for ldd i dont have the executable as it cant build...

[jsulm]

@Jimmy32 Remove space between -L and /usr/local/lib
You don't need the executable. What I meant is:

ldd /usr/local/lib/dlib.so

[Jimmy32]

@jsulm my library is static and i typed

ldd /usr/local/lib/libdlib.a 

but it gave me " not a dynamic executable "

[jsulm]

@Jimmy32 Did you remove the space? Don't forget to run qmake afterwards.

[Jimmy32]

@jsulm yes i did remove but still the same

[jsulm]

@Jimmy32 My guess is that dlib depends on some other libs you're currently not linking

[Jimmy32]

@jsulm after some search, dlib depends on pthread and x11

[Eyyup]

dlib installation and Qt - dlib linking
https://www.youtube.com/watch?v=YkTHq65FPa4