c - 符号重复错误-全局变量

所以我有三个文件:

jarvismarch.c
jarvismarchtools.c
jarvismarchtools.h

运行make后，我收到以下错误:

Andrew-Carpenters-Laptop:Independent Study ahcarpenter$ make
cc    -c -o jarvismarch.o jarvismarch.c
cc    -c -o jarvismarchtools.o jarvismarchtools.c
cc -o jarvismarch jarvismarch.o jarvismarchtools.o
ld: duplicate symbol _string1 in jarvismarchtools.o and jarvismarch.o for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [all] Error 1

string 1在jarvismarchtools.c中声明。 jarvismarchtools.h和jarvismarchtools.c中都包含jarvismarch.c。

关于如何解决此错误的任何想法？

在jarvismarchtools.h中:

/*
    FILENAME: jarvismarchtools.h
    AUTHOR: Andrew H. Carpenter
    DATE: 2 Feb 2013
    DESCRIPTION: This is a header file containing tools for running Jarvis' March.
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>

extern int string1 = 1;

typedef struct Point {
    double x, y;
    char *label;
} point;

/*
    DESCRIPTION: A function that determines the angle (in degrees) between two points.
    INPUT: Requires two points as input.

在jarvismarchtools.c中:

/*
    FILENAME: jarvismarchtools.c
    AUTHOR: Andrew H. Carpenter
    DATE: 2 Feb 2013
    DESCRIPTION: This is an implemenetation file containing tools for running Jarvis' March.
*/
#include "jarvismarchtools.h"

int string1 = 1;

float getAngle(point p1, point p2){

最佳答案

如果应该共享变量:

在标题

中将其设置为extern

在没有extern的C文件之一中定义它

如果不应该共享该变量，请在前面添加一个static。

关于c - 符号重复错误-全局变量，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/14763190/