Possible Duplicate:
What is an undefined reference/unresolved external symbol error and how do I fix it?
I recently started working on an interpreter in C++, but I got annoyed that vectors or arrays could not be passed to external class methods no matter what I tried and so I deleted everything I had worked on. As it turns out, I can't pass even an int to another class. I decided to give C++ another chance before resorting to C or Java, but the compiler still doesn't work as I would expect. Maybe I'm forgetting something simple about C++, as I haven't used it in a while, but this seems simple enough. My problem is: I can't pass arguments to methods in other classes when they're not defined in the same file. Here's what I'm trying to do:
Main: main.cpp
#include "myclass.h"
int main() {
MyClass test;
int n = test.add(25, 30);
return n;
}
Header: myclass.h
class MyClass {
public:
int add(int a, int b);
};
Class implementation: myclass.cpp
#include "myclass.h"
int MyClass::add(int a, int b) {
return a + b;
}
Compiling this with g++ main.cpp
yields
/tmp/ccAZr6EY.o: In function
main': main.cpp:(.text+0x1a): undefined reference to
MyClass::add(int, int)' collect2: error: ld returned 1 exit status
What the heck am I doing wrong? Also, the compiler yells at me for the same thing even if my functions aren't parameterized, so it must be a problem with the header.
Any help is much appreciated - thanks!