Compiler problem - collect2: error: ld returned 1 with ofxOpenCv

Hello. I am trying to create a project with ofxOpenCv with the project generator but when I try to run it it throw me the following error

collect2: error: ld returned 1

Eventually I want to use ofxCv. I am using qtcreator in ubuntu and if I comment out the ofxOpenCv line in the addons sections of the qbs file it works. I haven’t included ofxOpenCv.h yet. Any ideas? Thanks!