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"undefined reference to"-problem I'm not able to solve
Thanks in advance to everybody willing to help and reading this.
I'm willing to search and read but I'm totally stuck.
I want to write a little program that runs on Linux, Windows and hopefully on Android some day.
This program should use some libraries e.g. musicbrainz.
I compiled musicbrainz, installed it and added it to my project with qt-creator.
The .pro-file looks like this http://pastebin.com/3EH16jrw
and I copied the sourcecode from https://github.com/metabrainz/libmusicbrainz/blob/master/examples/cdlookup.cc
I commented everything out except one line http://pastebin.com/C3q3SsU0
Output is http://pastebin.com/uV547kxq
I have no clue why this is and I really need some help.
Rondog last edited by
You are likely not including all the files you are using in your pro file. For example, one of the include lines in your program looks like this:
but I don't see any reference to 'Query.cpp' in your PRO file. This is likely where the link error is coming from (?).
I don't know what musicbrainz is all about but there might be a 'PRI' file which will have a list of all the sources related to this software that needs to be added. You add a line to your PRO file to include the PRI file.
@Rondog He is linking against musicbrainz5 lib, so no need to add musicbrainz5 sources to the project.
@Proton Is the libmusicbrainz5.so located in one of the lib directories you pass to the linker?
"g++ -m64 -o Worker4Music main.o mainwindow.o mainworker.o musicbrain.o moc_mainwindow.o moc_mainworker.o -L/usr/X11R6/lib64 -L/home/proton/Dev/Worker4Music/../../../../usr/local/lib/ -ltag -lmusicbrainz5 -lQt5Widgets -lQt5Gui -lQt5Core -lGL -lpthread"
First of all, thanks for your help!
@Rondog: jsulm is write, I'm linking against musicbrainz library.
@jsulm: I don't really know what you mean. Path to musicbrainz lib is usr/local/lib/ and path to the project is /home/proton/Dev/Worker4Music/
Should I copy the library to a directory of the project?
@jsulm I'm still not quite sure what you mean. libmusicbrainz5.so is in the directory /usr/local/lib/ and if PWD is /home/proton/Dev/Worker4Music/ than "LIBS += -L$$PWD/../../../../usr/local/lib/ -lmusicbrainz5" states this directory, doesn't it?
I finally found my mistake. I wanted to copy the library to a directory in the build tree and than I saw there is also a libmusicbrainz5cc.so library. I used that instead and know my project compiles. Sorry for wasting your time and thanks again for your help!