Linking Dlib to QT application

Arqam

Okay, I have spent more than 2 days just in this but still not able to figure out how its to be done.

I have to link Dlib to my QT project. My .pro file is like this : https://pastebin.com/uiDsd3NA

In this if I add dlib code then I get :-1: error: linker command failed with exit code 1 (use -v to see invocation) error and :-1: error: [QTDlibXMLGenerator.app/Contents/MacOS/QTDlibXMLGenerator] Error 1 .

When I did normal inclusion of the external library it gave me linker error, which I resolved by adding source.cpp file in the SOURCES, then I started getting error related to X11 library and its development package, which I resolved using few extra lines in my .pro file as you can see (related to X11).

And now finally this is the present condition, i.e. the error messages that I showed.

mrjj

Hi
Did you compile the libdlib.a yourself ?

also QTDlibXMLGenerator is the Qt app (?), so it fails with error 1 in the linking phase?

Also what version of Xcode ?

seems 8 should be used ?
https://www.learnopencv.com/install-dlib-on-macos/

timday

@Arqam (Came here from your link in https://forum.qt.io/topic/82293/installation-size-macos ); sorry no idea I've never used dlib. I'd hope you could get some more detailed information about why the linker command is failing (undefined symbols? files not found?).

Arqam

@mrjj said in Linking Dlib to QT application:

https://www.learnopencv.com/install-dlib-on-macos/

I am using QT IDE only not XCode.
I used CMake to compile the libdlib.a .

mrjj

@Arqam
Ok. as long as you use same compiler for both lib and app.

Arqam

@mrjj I used the documentation to install QT, I didn't choose any compiler there. Did I do anything wrong?

mrjj

@Arqam
I dont think so but its easy to test.
Make default GUI app (via menu) and see if it runs.

Arqam

@mrjj I am able to run the default app which shows the window, I am also able to run openCV code by linking my openCV library.
But Dlib its throwing errors in the build

mrjj

@Arqam
Then it sounds like all is ok compiler wise.
Ccan you please try this
https://stackoverflow.com/questions/43795385/linker-command-failed-with-exit-code-1-use-v-to-see-invocation-xcode-8-swif

and if "reveal in log" tell more, post it here ?

Arqam

@mrjj I am getting this error :

ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) make: *** [XMLGenerator.app/Contents/MacOS/XMLGenerator] Error 1 01:18:21: The process "/usr/bin/make" exited with code 2. Error while building/deploying project XMLGenerator (kit: Desktop Qt 5.9.1 clang 64bit2) When executing step "Make"

The full terminal output with warnings : https://pastebin.com/azpD6Byh

Anything that I did wrong?

SGaist

Hi,

Might be a silly question but are you sure that all your dependencies are built for 64bit ?

patrik08

@Arqam said in Linking Dlib to QT application:

ld: symbol(s) not found for architecture x86_64 clang: error: linker

If you get error on type:

ld: symbol(s) not found for architecture x86_64 clang: error: linker

By my experience ist tipical that one or more function wo you use from the lib ist not inside... or not avaiable...
Use console

nm --help libname.a  /// or waht else

after you have all result from class & function inside the lib
typical resul: https://raw.githubusercontent.com/pehohlva/QCLD2/master/google_bridge/function.nm.txt

Mac architecture is very powerfull and give you all waht you need..
example .. today i discovery how to convert translate.tr file from qt to po . and back . and after translate online in many language... funny qt

&& qmake file on mac is better give the full path..
LIBS += -L/usr/local/opt/curl/lib -lcurl
is not like cmake that you say:

find_package(Boost COMPONENTS system thread REQUIRED)
find_package(CURL REQUIRED)

and all is run...

Arqam

This post is deleted!

Arqam

@SGaist I just included the library, I didn't see any dependecies that I had to handle.

My current .pro file is this : https://pastebin.com/5W6a0v9g

Arqam

@mrjj Also I saw just now, QT is compiled using qMake and dlib is compiled using CMake.

jsulm

@Arqam said in Linking Dlib to QT application:

QT is compiled using qMake and dlib is compiled using CMake

this doesn't matter, what matters is the compiler used to build them.