Question

I’m working on my first large C++ project, and I’m having huge problems getting it to build corectly.

first of all, the errors:

/tmp/ccn7hjru.o: In function `match(std::basic_istream<char, std::char_traits<char> >&, char const*)':
Geometry.cpp:(.text+0x0): multiple definition of `match(std::basic_istream<char, std::char_traits<char> >&, char const*)'
/tmp/ccfuS3Jb.o:Camera.cpp:(.text+0x0): first defined here
/tmp/ccn7hjru.o: In function `eat(std::basic_istream<char, std::char_traits<char> >&)':
Geometry.cpp:(.text+0xda): multiple definition of `eat(std::basic_istream<char, std::char_traits<char> >&)'
/tmp/ccfuS3Jb.o:Camera.cpp:(.text+0xda): first defined here
/tmp/ccIOhdcQ.o: In function `match(std::basic_istream<char, std::char_traits<char> >&, char const*)':
Light.cpp:(.text+0x0): multiple definition of `match(std::basic_istream<char, std::char_traits<char> >&, char const*)'
/tmp/ccfuS3Jb.o:Camera.cpp:(.text+0x0): first defined here
/tmp/ccIOhdcQ.o: In function `eat(std::basic_istream<char, std::char_traits<char> >&)':
Light.cpp:(.text+0xda): multiple definition of `eat(std::basic_istream<char, std::char_traits<char> >&)'
/tmp/ccfuS3Jb.o:Camera.cpp:(.text+0xda): first defined here
....

this goes on for hundreds of lines

All of my c++ course files look like this:

#include "Camera.h"
#include "util.h"

Camera::Camera() {
    // TODO Auto-generated constructor stub

}
Camera::Camera(int x, int y) {
    this->resX = x;
    this->resY = y;
}

Camera::~Camera() {
    // TODO Auto-generated destructor stub
}

...more class methods below...

and the header files all look like this:

#ifndef CAMERA_H_
#define CAMERA_H_

#include "SceneElement.h"
#include "P3D.h"
#include "Ray.h"
#define CAMERA_PRE "{CAM:"
#define CAMERA_POST ":CAM}"
#define TAG_LOCATION "LOC:"
#define TAG_PLANE "PLANE:"
#define TAG_UPPER_RIGHT "UR:"
#define TAG_UPPER_LEFT "UL:"
#define TAG_LOWER_RIGHT "LR:"
#define TAG_LOWER_LEFT "LL:"
#define TAG_RES_X "RESX:"
#define TAG_RES_Y "RESY:"

class Camera: public SceneElement {
public:
    P3D location;
    P3D upperLeft;
    P3D upperRight;
    P3D lowerLeft;
    P3D lowerRight;
    int resX, resY;
    Camera();
    Camera(int, int);
    virtual ~Camera();
    virtual void toStream(std::ostream &);
    virtual void fromStream(std::istream &);
    Ray getRay(int, int);
};

#endif /* CAMERA_H_ */

the one exception is a util file, which looks like this:

#include "util.h"
#include <iostream>
#include <stdlib.h>
#include <string.h>


void match(std::istream &str, const char* expected){
    int len = strlen(expected);
    char* fromStream =  (char*)malloc(len+1);
    str.read(fromStream, len);
    fromStream[len] = 0;
    if(strcmp(fromStream, expected)){
        std::cout << "expected " << expected << ", got " << fromStream << "\n";
        free(fromStream);
        exit(1);
    }
    free(fromStream);
}


void eat(std::istream &str){
    char c;
    while(c=str.peek(), c == ' ' || c == '\n' || c == '\t'){
        str.get();
    }
}

with a header file that looks like this:

#ifndef UTILS
#define UTILS

#include <iostream>

void match(std::istream &str, const char* expected);
void eat(std::istream &str);

#endif

Answer 1

Look into SceneElement.h, P3D.h and Ray.h. Most likely, you have included util.cpp in one of these header files.

Another possibility could be a definition of match() and eat() in one of the header files.