objective-c – 在clang编译期间无法找到objc.h

我正在尝试使用clang编译Objective-C Hello_world应用程序.这是来源：

#import <Foundation/Foundation.h>
int main (int argc,const char * argv[])
{
 NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
 NSLog (@"Hello world");
 [pool drain];
 return 0;
}

我用这个命令行：

. /usr/share/GNUstep/Makefiles/GNUstep.sh
clang h.m `gnustep-config --objc-flags` -lgnustep-base -o Hello

我收到以下错误：

clang: warning: argument unused during compilation: '--param ssp-buffer-size=4'
In file included from h.m:1:
In file included from /usr/include/GNUstep/Foundation/Foundation.h:30:
In file included from /usr/include/GNUstep/GNUstepBase/GSVersionMacros.h:193:
In file included from /usr/include/GNUstep/GNUstepBase/GSConfig.h:229:
/usr/include/GNUstep/GNUstepBase/preface.h:112:11: Fatal error: 'objc/objc.h'
      file not found
 #include <objc/objc.h>
          ^
1 error generated.

使用gcc的相同命令行工作正常.

任何想法如何解决这个丢失的objc.h错误？