Thread: Need Help With LNK2005 Error

I have a couple classes inside one of my header files which I need to access in two different .cpp files, so I tried to include the .h file in both. One of the class declarations looks like this:

Code:

class GamePlayers
{
public:
	GamePlayers();
	void AssignCard(CardTypes Card);
	void AssignPosition(PositionTypes Position);
private:
	CardTypes Hand[14];
	PlayerTypes PlayerID;
	PositionTypes Position;
	bool Human;
	int Score;
} Player1, Player2, Player3, Player4;

Now when I try to compile I get the following linker error for every member of either class:

Graphics.obj : error LNK2005: "class GamePlayers Player1" (?Player1@@3VGamePlayers@@A) already defined in Gameplay.obj

What do I need to do to fix this problem?

Use Header Guards .

Show us the header file containing the GamePlayer class in its entirety.

Originally Posted by LyTning94

Meaning???

EDIT: If you mean #ifndef/#define at the beginning of the header file and #endif at the end, I've already done that.

In that case... are you sure that Player1, Player2, Player3, Player4 are supposed to be global variables ?
Also, as your error message seems to suggest, try separating the different classes and sections of the code into namespaces.


*As 'rags_to_riches' said , posting some more code would be a good idea *

A C programmer guess at solution.
Removed the Global Player1, Player2, Player3, Player4
By changing

Code:

} Player1, Player2, Player3, Player4;

to

Code:

}

Tim S.

Originally Posted by manasij7479

In that case... are you sure that Player1, Player2, Player3, Player4 are supposed to be global variables ?

I need them to be global variables, if that's what you're asking.

Originally Posted by manasij7479

Also, as your error message seems to suggest, try separating the different classes and sections of the code into namespaces.

Sorry for my ignorance, but what does that mean?

At any rate, here's my header file as requested:

Code:

#ifndef GAMEPLAY_H
#define GAMEPLAY_H

#include "SDL.h"

enum PlayerTypes
{
	PLAYER_1,
	PLAYER_2,
	PLAYER_3,
	PLAYER_4
};

enum PositionTypes
{
	NO_POSITION = -1,
	POSITION_1,
	POSITION_2,
	POSITION_3,
	POSITION_4
};

enum CardTypes
{
	NO_CARD = -1,
	SPADES_ACE,
	SPADES_2,
	SPADES_3,
	SPADES_4,
	SPADES_5,
	SPADES_6,
	SPADES_7,
	SPADES_8,
	SPADES_9,
	SPADES_10,
	SPADES_JACK,
	SPADES_QUEEN,
	SPADES_KING,
	DIAMONDS_ACE,
	DIAMONDS_2,
	DIAMONDS_3,
	DIAMONDS_4,
	DIAMONDS_5,
	DIAMONDS_6,
	DIAMONDS_7,
	DIAMONDS_8,
	DIAMONDS_9,
	DIAMONDS_10,
	DIAMONDS_JACK,
	DIAMONDS_QUEEN,
	DIAMONDS_KING,
	CLUBS_ACE,
	CLUBS_2,
	CLUBS_3,
	CLUBS_4,
	CLUBS_5,
	CLUBS_6,
	CLUBS_7,
	CLUBS_8,
	CLUBS_9,
	CLUBS_10,
	CLUBS_JACK,
	CLUBS_QUEEN,
	CLUBS_KING,
	HEARTS_ACE,
	HEARTS_2,
	HEARTS_3,
	HEARTS_4,
	HEARTS_5,
	HEARTS_6,
	HEARTS_7,
	HEARTS_8,
	HEARTS_9,
	HEARTS_10,
	HEARTS_JACK,
	HEARTS_QUEEN,
	HEARTS_KING,
	RED_JOKER,
	BLACK_JOKER
};

class GamePlayers
{
public:
	GamePlayers();
	void AssignCard(CardTypes Card);
	void AssignPosition(PositionTypes Position);
private:
	CardTypes Hand[14];
	PlayerTypes PlayerID;
	PositionTypes Position;
	bool Human;
	int Score;
} Player1, Player2, Player3, Player4;

class Cards
{
public:
	Cards();
	void ApplyCard(int X, int Y);
private:
	SDL_Rect Clip;
	CardTypes CardID;
	PlayerTypes Owner;
	int Value;
} BlackJoker, RedJoker, SpadesTwo, DiamondsTwo, ClubsTwo, HeartsTwo,
	SpadesAce, DiamondsAce, ClubsAce, HeartsAce, SpadesKing, DiamondsKing, ClubsKing, HeartsKing,
	SpadesQueen, DiamondsQueen, ClubsQueen, HeartsQueen, SpadesJack, DiamondsJack, ClubsJack, HeartsJack,
	SpadesTen, DiamondsTen, ClubsTen, HeartsTen, SpadesNine, DiamondsNine, ClubsNine, HeartsNine,
	SpadesEight, DiamondsEight, ClubsEight, HeartsEight, SpadesSeven, DiamondsSeven, ClubsSeven, HeartsSeven,
	SpadesSix, DiamondsSix, ClubsSix, HeartsSix, SpadesFive, DiamondsFive, ClubsFive, HeartsFive,
	SpadesFour, DiamondsFour, ClubsFour, HeartsFour, SpadesThree, DiamondsThree, ClubsThree, HeartsThree;

static PlayerTypes Dealer = PLAYER_1;

GamePlayers* GetPlayer(PlayerTypes PlayerID);
Cards* GetCard(CardTypes CardID);

#endif

You don't define global variables in a header file. You declare them extern in the header file, and then in one (and only one) source file you define them.

I changed them to extern in the header file and then defined them all in another file as suggested. It works great now. Thanks for the help.