There are two separate errors.
First, you forgot to add main.cpp
to your makefile.
Second, your main.cpp
doesn’t contain a global function named main
. A class member function named main
doesn’t qualify. You need a function named main
in the global namespace with external linkage.
solved Makefile issue (Undefined symbols for architecture x86_64: “_main”, referenced from: implicit entry/start for main executable) [duplicate]