Makefile：函数的多重定义

Question

我正在尝试编写更复杂的makefile，但是我的探索让我陷入了多重定义问题。

该程序旨在强制使用大理石迷宫，因此我在marbleBoard.h中声明了一个游戏板类，其实现用marbleBoard.cpp编写。 .cpp文件#includes .h文件。主程序用marble.cpp编写。变量NORTH，SOUTH，EAST和WEST指的是代表墙的位掩码，并在类外的marbleBoard.h中定义。

我将我的makefile基于MrBook的教程Makefiles。

这是Makefile代码：

#!/bin/bash

COMPILER=g++

CFLAGS=-c -g -std=c++14

all: marble

marble: marble.o marbleBoard.o
    $(COMPILER) marble.o marbleBoard.o -o marble

marble.o: marble.cpp
    $(COMPILER) $(CFLAGS) marble.cpp

marbleBoard.o: marbleBoard.cpp marbleBoard.h
    $(COMPILER) $(CFLAGS) marbleBoard.cpp marbleBoard.h

clean:
    rm *o marble

这是我收到的输出：

[uthranuil@Palantir marble]$ make
g++ -c -g -std=c++14 marbleBoard.cpp marbleBoard.h
g++ marble.o marbleBoard.o -o marble
marbleBoard.o:(.data+0x0): multiple definition of `NORTH'
marble.o:(.data+0x0): first defined here
marbleBoard.o: In function `marbleBoard::marbleBoard()':
/home/uthranuil/csci242/marble/marbleBoard.cpp:6: multiple definition of `EAST'
marble.o:(.data+0x1): first defined here
marbleBoard.o: In function `marbleBoard::marbleBoard()':
/home/uthranuil/csci242/marble/marbleBoard.cpp:6: multiple definition of `SOUTH'
marble.o:(.data+0x2): first defined here
marbleBoard.o: In function `marbleBoard::marbleBoard()':
/home/uthranuil/csci242/marble/marbleBoard.cpp:6: multiple definition of `WEST'
marble.o:(.data+0x3): first defined here
collect2: error: ld returned 1 exit status
make: *** [makefile:10: marble] Error 1

我花了很多时间寻找答案并尝试不同的解决方案。这是我读过的Q / As列表：
Function multiple definition linker error building on GCC - Makefile issue {
{3}} {
{3}} {
{3}} {
{3}}

非常感谢任何帮助。感谢您的时间和关注。