Objective-c链接错误与重复符号错误

时间:2010-06-19 22:11:38

标签: objective-c linker duplicates symbols

我是Objective C的新手,在尝试导入我定义的类时出现以下错误

Building target “MusicCube” of project “MusicCube” with configuration “Debug” — (1 error)
     cd /Users/varsha_vijay/Downloads/MusicCube
    setenv MACOSX_DEPLOYMENT_TARGET 10.5
    setenv PATH "/Xcode3.1.4/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Xcode3.1.4/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
    /Xcode3.1.4/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.2 -arch i386 -isysroot /Xcode3.1.4/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator3.1.sdk -L/Users/varsha_vijay/Downloads/MusicCube/build/Debug-iphonesimulator -F/Users/varsha_vijay/Downloads/MusicCube/build/Debug-iphonesimulator -filelist /Users/varsha_vijay/Downloads/MusicCube/build/MusicCube.build/Debug-iphonesimulator/MusicCube.build/Objects-normal/i386/MusicCube.LinkFileList -mmacosx-version-min=10.5 -framework Foundation -framework UIKit -framework OpenGLES -framework QuartzCore -framework AudioToolbox -framework CoreGraphics -framework OpenAL -o /Users/varsha_vijay/Downloads/MusicCube/build/Debug-iphonesimulator/MusicCube.app/MusicCube
ld: duplicate symbol _num_flight_vertices in /Users/varsha_vijay/Downloads/MusicCube/build/MusicCube.build/Debug-iphonesimulator/MusicCube.build/Objects-normal/i386/Flight.o and /Users/varsha_vijay/Downloads/MusicCube/build/MusicCube.build/Debug-iphonesimulator/MusicCube.build/Objects-normal/i386/EAGLView.o
collect2: ld returned 1 exit status
  ld: duplicate symbol _num_flight_vertices in /Users/varsha_vijay/Downloads/MusicCube/build/MusicCube.build/Debug-iphonesimulator/MusicCube.build/Objects-normal/i386/Flight.o and /Users/varsha_vijay/Downloads/MusicCube/build/MusicCube.build/Debug-iphonesimulator/MusicCube.build/Objects-normal/i386/EAGLView.o
  collect2: ld returned 1 exit status
Build failed (1 error)

以下是我的计划的组织方式。

1。我定义了一个c头文件vertices.h

#ifndef VERTICES_H
#define VERTICES_H
const int num_flight_vertices = 8;
#endif

2。我在Flight.h类中导入此头文件

#import "vertices.h"

@interface Flight : NSObject {

3。我正在我的EAGLView.h类中导入这个Flight.h文件

#import "vertices.h"
@interface EAGLView : UIView {
@private
Flight *flight;

当我构建它时,我得到了错误。

有人可以帮助我。

谢谢, VJ

1 个答案:

答案 0 :(得分:7)

您是否在项目的其他任何位置导入vertices.h

通常,您在头文件中声明常量,并在实现文件中定义它们,这可以避免此问题。所以你可以这样做:

// vertices.h
#ifndef VERTICES_H
#define VERTICES_H
extern const int num_flight_vertices;
#endif

// vertices.c
#import vertices.h
const int num_flight_vertices = 8;